Maine

Infectious Salmon Anemia Virus

Control Program Standards

USDA APHIS Veterinary Services

Revised: July 2017

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Building, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202)720-5964 (voice and 

TDD). USDA is an Equal Opportunity provider and employer.
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Table of Contents

EXECUTIVE SUMMARY......................................................................................................................3

INTRODUCTION AND BACKGROUND ............................................................................................4

MAJOR ISAV CONTROL PROGRAM COMPONENTS ..................................................................9

PART I. DEFINITIONS ........................................................................................................................11

PART II. ADMINISTRATIVE PROCEDURES............................................................................16

A. SUPERVISION OF THE ISAV CONTROL PROGRAM......................................................................16

B. ACCESS TO SITES ........................................................................................................................17

C. ISA TECHNICAL BOARD.............................................................................................................17

D. CONFIDENTIALITY......................................................................................................................18

PART III. DISEASE SURVEILLANCE AND INVESTIGATION...................................................18

A. BASIC REQUIREMENTS ...............................................................................................................18

B. SURVEILLANCE REQUIREMENTS ................................................................................................19

C. SAMPLE SPECIFICATIONS............................................................................................................20

D. DIAGNOSTIC TESTS AND DIAGNOSTIC TESTING STANDARDS ...................................................21

E. BIOSECURITY AUDITS.................................................................................................................22

F. REPORTING.................................................................................................................................23

PART IV. STANDARDS FOR DISEASE CONTROL ACTIONS AND MANAGEMENT .......24

A. ISAV CONTROL PROGRAM CATEGORIES...................................................................................24

B. QUARANTINES............................................................................................................................26

C. INDEMNITY.................................................................................................................................26

D. DEPOPULATION ..........................................................................................................................27

E. PERMITTING ...............................................................................................................................28

F. CLEANING AND DISINFECTION...................................................................................................28

G. FALLOWING................................................................................................................................28

APPENDIX A: FISH HEALTH, BIOSECURITY, AND CLEANING & DISINFECTION ..........35

EFFECTIVE DISINFECTANTS ...............................................................................................................35

CLEANING & DISINFECTION LEVELS.................................................................................................35

CLEANING AND DISINFECTION PROTOCOLS FOR SPECIFIC AREAS OF OPERATION:.....................36

A. VESSELS & WHARVES ..............................................................................................................36

B. PERSONNEL & GENERAL EQUIPMENT ....................................................................................37

C. CONTAINMENT NETS & PENS ..................................................................................................37

D. DIVERS AND DIVING GEAR........................................................................................................37

E. DEAD FISH & BLOOD-WATER COLLECTION, STORAGE, AND DISPOSAL................................38

F. BROODSTOCK & EGGS .............................................................................................................38

APPENDIX B: NOTIFICATION GUIDANCE FOR LABORATORY AND VS PERSONNEL...39

APPENDIX C: ISAV CONTROL PROGRAM CONTACTS ...........................................................41

APPENDIX D: USDA APHIS ISAV CONTROL PROGRAM FLOW CHARTS...........................44

APPENDIX E: USDA SAMPLE SUBMISSION FORM....................................................................45

LIST OF TABLES

TABLE 1: SAMPLE SPECIFICATIONS FOR ISAV CONTROL PROGRAM APPROVED ASSAYS.............................21

TABLE 2: ISAV CONTROL PROGRAM CATEGORIES AND DESCRIPTION..........................................................24
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Executive Summary 

The United States Department of Agriculture, (USDA), Animal and Plant Health Inspection 

Services, (APHIS), Veterinary Services, (VS) Infectious Salmon Anemia Virus Control Program 

Standards, hereafter referred to as the Standards, establish recommended procedures for the 

prevention and containment of Infectious Salmon Anemia virus (ISAV) in farm-raised Atlantic 

salmon (Salmo salar). The Standards provide guidelines for producers, APHIS-accredited 

veterinarians, other fish health personnel, laboratory personnel, and regulators. The eligibility of 

Atlantic salmon producers affected by ISA in Maine to receive indemnity is based, in part, on 

compliance with these Standards, and upon availability of any indemnity funds (See 9 CFR 53.10

for additional details). These Standards were originally written in 2001 by the USDA APHIS VS 

after numerous meetings, consultations, and discussions with members the Standards Committee of 

the Maine/USDA APHIS VS ISA Joint Working Group. These Standards have been revised twice 

since then, by the ISA Technical Board, to reflect updated information regarding ISAV/ISA 

transmission, diagnostic tests, and control processes.
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Introduction and Background 

Infectious salmon anemia (ISA) is an important disease of Atlantic salmon (Salmo salar) caused by 

infectious salmon anemia virus (ISAV). Detections of the virus, or clinical outbreaks of disease 

caused by it, are notifiable to the World Organization for Animal Health (OIE) by competent 

authorities worldwide. All suspect detections of ISAV or outbreaks of ISA in the U.S. are reportable 

to USDA APHIS Veterinary Services as the Federal competent authority for animal health. 

ISAV is found in farmed or free-ranging fish in freshwater and marine settings. While ISA is a 

disease of marine farmed Atlantic salmon (OIE, 2016), the species in which ISAV detections have 

been made include Atlantic salmon (Salmo salar), rainbow trout (Oncorhynchus mykiss), brown trout 

(Salmo trutta), and pollock (Pollachius virens). ISAV does not affect humans or other mammals and 

the virus has not been shown to replicate at typical mammalian temperatures (Falk et al, 1997).

Both ISAV infection and any resulting disease are of serious global concern for the farmed Atlantic 

salmon industry. Outbreaks of ISA have impacted Atlantic salmon production in Norway, Scotland 

(and other parts of the UK), the Faroe Islands, Maritime Canada, the U.S. (Maine only), and Chile. 

Hemorrhagic kidney syndrome (HKS) in Atlantic salmon from New Brunswick, Canada was first 

described in 1998, and appears in retrospect to be the first account of ISA in North America (Mullins 

et al., 1998). The first isolate of ISAV discovered in Maine in 1999 was determined to be the same 

strain as the New Brunswick 1998 HKS virus (Bouchard et al., 1999; Blake et al., 1999). Outbreaks 

of ISA between 1999 and 2003 in Maine and Maritime Canada caused devastating economic losses 

to the industry in both countries.

Taxonomically, ISAV is the type species of the genus Isavirus, in the Orthomyxoviridae family 

(ICTVdB Index of Viruses), which also includes influenza viruses. The genome of ISAV is 

comprised of eight single-stranded segments of RNA of negative polarity. Virus particles are 

pleomorphic, enveloped, and 100-130 nm in diameter with 10-12 nm surface projections. ISAV is 

inactivated by external heat (>56°C), extreme pH (<4 or >12), UV, ozone and a variety of 

disinfectants containing chlorine, iodine or potassium peroxymonosulfate compounds (Falk et al., 

1997). Virus persistence is also likely influenced by environmental factors such as temperature, 

salinity, presence of organic material, presence of other pathogens and exposure to UV radiation

(OIE, 2016).
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Route of infection and clinical signs

Gill tissue is considered the main route of ISAV entry (Weli et al., 2013), though skin and 

gastrointestinal tract are also noted (Rolland and Nylund, 1998a). ISAV infects endothelial cells in 

blood vessels, kidney and heart tissues (Aamelfot et al., 2012), resulting in internal and external 

hemorrhages in affected fish (OIE 2016). 

Morbidity and mortality due to ISA are highly variable. Cumulative mortality varies greatly from 

near zero to a majority of fish on a given site. Outwardly, affected fish may show few signs of 

infection or disease until late in a given disease cycle, or may alternatively exhibit a variety of 

associated signs including pale gills, exophthalmia or bulging eyes (with or without hemorrhage), 

lethargy, petechiae (pinpoint hemorrhages) on the skin, and darkened skin surfaces. Gross internal 

lesions are also highly variable and may include: 1) fluid accumulation in the peritoneal (ascites) or 

pericardial spaces, 2) hemorrhagic lesions along the GI tract, mesenteric fat, swim bladder or 

peritoneum, and 3) hemorrhagic lesions, congestion or swelling of the liver, spleen and kidney 

capsule. Microscopic lesions can include congestion and necrosis in the liver, heart, blood vessels, 

spleen and kidneys. (OIE, 2016).

Epidemiological factors

Transmission of ISAV is believed to occur principally through horizontal routes. Virus is shed into 

the environment through blood, mucus, feces, urine, skin or carcasses of infected fish (Vike et al., 

2014). Epidemiological investigations suggest the virus also spreads between aquaculture sites via 

untreated wastes and water from harvest operations or processing plants (Vagsholm et al., 1994),

natural circulation of water between infected and uninfected sites (Gustafson et al., 2007a; Mardones 

et al, 2009; Aldrin et al., 2011), wild fish (McClure et al., 2005), a shared work force (Vagsholm et 

al., 1994; Hammell and Dohoo, 2005), and shared equipment or gear that have not been properly 

disinfected at marine sites (Hammell and Dohoo, 2005; Ellis et al., 2006). 

An investigation of ISA in first-feed Atlantic salmon fry raised the possibility of infection at very 

early life stages through contaminated ovarian fluids (Nylund et al., 1999). Though this theory is 

debated, recent evidence suggests at least some ISAV genotypes may be transmitted vertically (i.e., 

from parent to offspring) through infected eggs (Marshall et al., 2014). 

Arthropods such as sea lice (Lepeophtheirus salmonis and Caligus sp.) are considered potential 

pathogen vectors, but their significance in ISAV transfer is still under study (Valdes-Donoso et al., 
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2013). Secondary effects such as stress or tissue damage may also increase disease susceptibility 

(Rolland and Nylund, 1998a). Little supporting evidence is available to demonstrate that other marine 

species act as efficient ISA virus carriers or reservoirs capable of infecting cultured Atlantic salmon. 

Genomic information

Sequence comparisons of genome segments 2, 5, 6 and 8 of ISAV isolates identify two distinct 

genotypes: Genotype I and Genotype II (Kibenge et al., 2001; Krossoy et al., 2001; Kibenge et al., 

2009). Genotype I, also termed ‘European’, is commonly affiliated with Atlantic salmon in Norway, 

Scotland, Shetland Islands and the Faroe Islands; however, there have been several detections of this 

genotype in North America (pers. comm. Michael Beattie, NBDAAF). Genotype II, also termed 

‘North American’, is predominantly associated with Atlantic salmon in North America. Studies of 

isolates from Norway, Scotland, and Canada indicate that these two subtypes appear to have diverged 

more than 100 years ago (Krossoy et al., 2001). A 2007 outbreak in Chile involved Genotype I and 

has been tentatively linked to trade of eyed embryos from Norway (Kibenge et al., 2009; Vike et al., 

2009). 

Phylogenetic studies of surface glycoprotein gene sequences encoded on ISAV segments 5 and 6 

further subdivide Genotype I into three geno-groups, EU-G1, EU-G2 and EU-G3 (Nylund et al., 

2003; Devold et al., 2006; Kibenge et al., 2009). Genotype II variability appears less substantive, so 

this genotype has not been similarly subdivided. Genotyping and geno-grouping (if an EU genotype) 

are important for phylogenetic tracing.

Additionally, genetic variation among isolates has been investigated for use as markers of virus 

virulence or dissemination between farms and regions (Krossoy et al., 2001a), with a focus on gene 

segments encoding surface hemagglutinin-esterase (HE, segment 6) and fusion (segment 5) proteins 

(Nylund et al., 2003; Godoy et al., 2013). Currently, the greatest genetic variability is found in a 

region of the HE gene termed the highly polymorphic region (HPR), encoding the stem of the HE 

protein. Many amino acid patterns have been described for this HPR (Aamelfot et al., 2014). To 

date, all clinical ISAV variants include gaps in the HPR sequence, hypothesized to arise through 

deletions from a full-length precursor gene termed HPR0 (EFSA, 2012). These variants, commonly 

associated with clinical outbreaks, are loosely referred to as ‘HPR-deleted’ (OIE 2016). In contrast, 

HPR variants having full-length HPR sequences are termed ‘HPR0’. To date HPR0 variants have 

proven non-culturable and have never been associated with disease (Ritchie et al., 2001; Kibenge et 
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al., 2009; Godoy et al., 2013). While isolates with the HPR0 signature display tissue tropism for gill 

epithelium (Christiansen et al., 2011), HPR0 infection does not appear to cause ISA clinical signs or 

increased mortality (Christiansen et al., 2011; Godoy et al., 2013). 

HPR0 variants occur in salmon production regions globally (Kibenge et al., 2009; Christiansen et al., 

2011; Lyngstad et al., 2011; Vanderstiche et al., 2014). Detections of HPR0 variants have been 

documented antecedent to, concurrent with, or subsequent to detections of HPR-deleted variants. 

Additionally, co-detections of different HPR-deleted variants (Aldrin et al., 2011), or detections of 

both deleted and non-deleted variants (Gustafson et al., 2008; Kibenge et al., 2009; Cardenas et al., 

2014) are occasionally reported from single fish or sites. Field research has also shown phylogenetic 

and temporal relationships between HPR0 and virulent variants in some locations (Lyngstad et al., 

2007, 2011; Godoy et al., 2013). However, these few findings, and relatively ubiquitous occurrence 

of HPR0 variants, suggest that the emergence of HPR-deleted from non-deleted virus is likely a low 

probability event. 

An alternative hypothesis suggests HPR0 could instead, or also, derive from insertions and 

attenuation of HPR-deleted viruses (Kibenge et al., 2007; Kibenge et al., 2012; Castro-Nallar et al., 

2011). The majority of pathogenic ISAV isolates confirmed to date in Maine and New Brunswick

have been classified Genotype II (Nylund,et al., 2003; Kennebec River Biosciences, Inc. pers. comm; 

New Brunswick Department of Agriculture, Aquaculture & Fisheries, pers. comm.). In contrast, the 

HPR0 variants detected in Maine and Maritime Canada are typically classified Genotype I (Ritchie 

et al., 2001; Cook-Versloot et al. 2004; Gustafson et al., 2008). 

In addition to deletions in the HPR, ISAV virulence appears co-dependent on insertions or mutations 

in the fusion (F) protein gene (Devold et al., 2006; Markussen, et al., 2008; Cardenas et al., 2014) and 

possibly other less-studied sections of the ISAV genome (Markussen et al., 2008). Initial studies 

propose a multi-step evolutionary process, citing transitional stages (HPR-deleted without a fusion 

protein mutation), wherein an HPR deletion alone may not be enough to infer virulence (Cardenas et 

al., 2014). Thus, further evaluation of the HE gene (e.g., the 5’ end) and other regions of the ISAV 

genome is advised to best establish relatedness or infer pathways of disease spread (Aldrin et al., 

2011; Lyngstad et al., 2011; Godoy et al., 2013).
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Management impacts

In December 2001, the US Secretary of Agriculture declared an animal disease emergency in response 

to ISAV emergence in a highly productive salmon farming region in Maine. In January 2002, APHIS 

VS and the State of Maine, in collaboration with the local industry, instituted the ISAV Control 

Program to oversee disease response at affected Atlantic salmon farming sites in affected regions. 

Program standards, eligibility for indemnification of specified losses, harmonization of control 

actions with neighboring New Brunswick, and strong cooperation (including the implementation of 

strict biosecurity protocols) from salmon producers in the U.S. and Canada ultimately led to resolution 

of ISA disease in the region (Ellis et al., 2006). The last detection of ISAV (HPR-deleted) associated 

with this event occurred in February 2006. Several findings have been reported in Canada since then, 

though these have been localized and responsive to control. However, ISAV HPR0, as confirmed by 

sequence analysis, has been periodically detected by RT-PCR at sites in Maine and Maritime Canada 

since 2003. 

Experience with ISA outbreaks at Atlantic salmon marine sites in Europe, North America and Chile

indicates that HPR-deleted ISAV genotypes can spread variably from net-pen to net-pen or site to site

if outbreaks are not controlled. Onset of disease may be extended by several months in some netpens and may be influenced by: speed of infected net-pen removal (McClure et al., 2004; Gustafson 

et la., 2006; Mardones et al., 2013), water temperature and length of time the fish have been in 

saltwater, fish density (Mardones et al., 2013), vaccination status, sea lice, nutrition, environmental 

or management conditions (Hammell and Dohoo, 2005; Gustafson et al., 2007b), and the immune 

competency of exposed fish. Coordination of production activities through the hydrographic 

delineation of management areas, single year-class stocking of sites, synchronized fallowing within 

management areas, rigorous biosecurity, and movement restrictions have also been deemed important 

in the resolution of ISA outbreaks in the United States (Ellis et al., 2006) and other countries (Murray 

et al., 2010; Gustafson et al., 2014; Mardones et al., 2014).
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Major ISAV Control Program Components

The ISAV Control Program was implemented in Maine in January 2002 and is a joint collaboration 

among the United States Department of Agriculture, Animal and Plant Health Inspection Service 

Veterinary Services (USDA APHIS VS), the Maine Department of Marine Resources, APHISaccredited veterinarians, APHIS-approved diagnostic laboratories, the National Veterinary Services 

Laboratories in Ames, IA, and producers of cultured Atlantic salmon.

The ISAV Control Program consists of seven components: surveillance, laboratory testing, disease 

reporting, disease control and biosecurity, quarantine, depopulation, and indemnity (subject to 

availability of funding). Other related aspects include, the development of action plans, risk 

identification and mitigation, movement restrictions, selective depopulation, synchronized fallowing, 

overall management coordination and shared communications among marine farming operations 

involving Atlantic salmon. 

Frequent, targeted surveillance ensures that ISAV incursions will be quickly detected when present. 

Testing with currently approved assays at an APHIS-approved laboratory facilitates a prompt and 

accurate diagnosis. Reporting procedures ensure that once infected or diseased fish are identified, 

control measures can proceed rapidly. Disease control practices such as biosecurity measures and 

integrated pest management can also mitigate pathogen and disease introduction or spread. Prompt 

depopulation of net-pens infected with HPR-deleted ISAV eliminates a continuing transmission risk. 

Finally, indemnity funds, when available, provide financial relief to producers while encouraging 

prompt reporting and compliance with the Standards.

While elimination of the ISA virus from the marine environment may not be realistic because of the 

complexity of the marine ecosystem, elimination of the disease from aquaculture operations is an 

achievable goal. Fish health regulatory agencies in other countries, and many Atlantic salmon 

producers through their Best Management Practices or international certification regimens, have 

developed similar approaches to disease management for ISA. 

The farmed salmon producers in Maine and Maritime Canada utilize highly qualified personnel 

experienced in all aspects of fish culture, husbandry, and health management. Producers have 

established comprehensive internal procedures for increased disease surveillance, and utilize working 
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relationships with aquaculture veterinarians and diagnostic laboratories to provide further technical 

expertise. The producers comply with applicable fish health inspections needed to meet import and 

export regulatory requirements for fish movements. Current state-level requirements in Maine

include, at minimum, annual health inspections for all lots of Atlantic salmon (or other salmonid fish

species) before transfer from freshwater hatcheries to marine sites; and testing of Atlantic salmon

broodstock at spawning. Additional elective diagnostic sampling may also be conducted to meet 

individual hatchery or marine site management protocols and production requirements. 

Producers of farmed Atlantic salmon in Maine have worked, over time, with the Maine Aquaculture 

Association, academic and private–sector disease researchers, and regulatory agencies to establish 

biosecurity protocols, best management practices, integrated pest management and bay management 

approaches for aquaculture operations. These have included the use of risk assessments, biosecurity 

audits, and the designation of fish health zones. To ensure that objectives for ISA control are

consistently implemented before, during, and after any ISA outbreaks, the Maine Department of 

Marine Resources (DMR) established regulations (Chapter 24.21) to define fish health zones (also 

termed bay management areas or restricted areas), require mandatory ISA virus surveillance and 

reporting, and restrict finfish aquaculture vessel and equipment movements. In addition, these 

Standards were developed to specify the testing procedures necessary to confirm ISA virus, stipulate 

chain of custody requirements, standardize sampling requirement protocols, identify responsible 

inspectors, and stipulate consequent actions upon detection of ISA virus. 

Since 2002, Maine farmed salmon producers have prioritized single year-class stocking, as well as 

zoned site management strategies. In view of the uncertainty surrounding potential vertical 

transmission of ISA virus, Atlantic salmon producers have voluntarily adopted precautionary 

measures that apply to many areas of fish husbandry to limit the risk of vertical transmission. These 

measures include broodstock pre-screening for ISA virus, and thorough egg disinfection protocols at 

fertilization and water hardening. Due to shared water resources, as well as potentially shared 

personnel and equipment by producers raising fish in both Canada (especially New Brunswick) and 

Maine, the continuous communication, coordination and harmonization of ISA management 

programs between the two countries is considered essential.
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Part I. Definitions

Accredited veterinarian: a veterinarian holding a current Maine State veterinary license, whom has 

also fulfilled the current accreditation requirements for Category II as specified by the United States 

Department of Agriculture Animal and Plant Health Inspection Service (USDA, APHIS) See Part II

F

Action Plan: a document that defines response contingencies for a particular threat such as a pathogen 

or disease

Active site: a marine finfish culture site as designated by the Maine DMR, and at which fish are 

present 

Approved laboratory: a laboratory that is approved to conduct official diagnostic tests for ISA virus 

by the USDA APHIS laboratory approval processes (Reference VS memorandum 567.2) See Part III 

F

Assays: specific diagnostic tests for the detection of pathogens

Atlantic salmon: for this document, all strains of Salmo salar being raised or maintained under 

cultivation conditions 

Biosecurity: procedures designed to eliminate or lessen physical, economic, and other losses 

involving farmed stocks. Among other elements, risks of acquiring or transmitting pathogens are 

assessed and factored into a comprehensive program involving aspects of site design, stock selection, 

and husbandry practices, therapeutic agents, veterinary supervision, and many other management 

variables (See Appendix A)

Biosecurity audit: onsite visit to a hatchery, marine site, processing plant, vessel or facility servicing 

or involved with aquaculture operations to assess biosecurity and/or audit management practices for 

compliance with recommended or generally accepted biosecurity protocols (See Appendix A or Part 

II E)

Blood-water: water mixed with blood from harvested fish. This may be found in stun or bleed tanks, 

vessel holds, container boxes, or processing plants

Broodstock: reproductively mature fish that have been selected or used as a part of a defined 

breeding program. These fish will be separately valued as ‘broodstock’ for any indemnification 

purposes

Broodstock candidates: a group of animals from which it is anticipated that the final broodstock will 

be selected. These fish will be separately valued as ‘production fish’ for any indemnification purposes
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Cell culture: the process by which cells are grown under controlled conditions, generally outside of 

their natural environment; See Virus Isolation

Clinical signs: any visual signs of disease by gross external or internal examination 

Depopulation: removal of all fish of a defined fish population within a net-pen, lease site, or other 

venue with the intent of eliminating a disease outbreak

Dip net: apparatus for removing fish from the surface water of net-pens. 

Disease: a syndrome including clinical signs, impairment, and/or mortality resulting from infection 

with a pathogen or from other causes such as water quality, environmental factors, nutrition, genetics, 

etc.

Disease of Regulatory Concern: infectious disease that has been demonstrated to cause a significant 

increase in the risk of mortality among salmonid populations in the State of Maine. Diseases of 

Regulatory concern are defined in Maine DMR Chapter 24 Regulations (See section 24.21)

DMR: The Maine Department of Marine Resources

Fallow: the status of a site or defined management zone once all animals have been removed and all 

equipment has been cleaned and disinfected; See Part IV G

Fallowing time: the period of time that a previously active site or defined management zone is empty 

of animals; this period begins after depopulation/harvest and upon the completion of the cleaning and 

disinfection of all associated enclosures, equipment and other fomites and it ends when restocking 

begins; See Part IV G

Fish Health Zone: defined marine geographic area as designated in Maine DMR Chapter 24

regulations (See section 24.01), also termed bay management area 

Genotype: the particular combination of alleles for a particular gene or locus

Gross Pathology: any visual signs of disease in fish organs or tissues by gross external or internal 

examination

Harvest: the removal of fish from enclosures, generally for transportation to a processing plant. 

Removal usually occurs by means of either containment in a vessel hold (live or dead), or by 

containment in refrigerated boxes after slaughter on the site

HPR0 ISAV: Sequence analysis reveals a putative “full-length” nucleotide sequence (105 

nucleotides = 35 amino acids) for the highly polymorphic region of gene segment 6 which encodes 

the stem of the HE protein of ISAV.
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HPR-deleted ISAV: Sequence analysis reveals gaps in the nucleotide sequence for the highly 

polymorphic regions of gene segment 6 which encodes for a shortened stem region (11 to 34 amino 

acids) of the HE protein of ISAV. 

Indemnity: compensation paid to producers of Atlantic salmon or other cultured susceptible species

in exchange for depopulation; See Part IV C

IFAT: indirect fluorescent antibody test; an assay that incorporates the binding capacity of specific 

antibodies to selected antigens. The IFAT makes use of a fluorescently tagged secondary antibody 

that binds to a primary antibody specific to the target antigen or pathogen. 

Import: to land on, bring into, or deposit, in any place subject to the jurisdiction of the State of 

Maine from outside the State of Maine

Inspection: an on-site visit and/or a sampling of fish, and the resulting laboratory tests and inspection 

reports conducted by an inspector in accordance with the testing requirements and procedures set 

forth in these Standards

Inspector: means an APHIS-accredited, licensed veterinarian, an AFS-certified (American Fisheries 

Society-certified) fish health inspector, or other persons recognized by federal or state agencies with 

responsibility for fish health or transfer in the state from which the fish or gametes originate; See

Accredited Veterinarian

Integrated Pest Management Plan: Producer’s IPM program considered the State of Maine 

Program when submitted by the producer to enroll in the Maine ISA Program. 

ISA: infectious salmon anemia; the clinical disease resulting from infection by a pathogenic genotype 

of ISA virus 

ISAV: Infectious salmon anemia virus, all known variants

ISA Program Categories: staged categories of ISA status; See Table 2

ISAV Control Program Veterinarian: USDA APHIS SPRS VS employee, assigned by the VS 

District 1 Director (DD) or District 1 Assistant Director (AD), to manage the ISA Program in Maine, 

and who reports to the District 1 DD or AD.

ISA Technical Board: a group of four voting members approved by the District 1 AD or delegate; 

consisting of the USDA ISAV Control Program Veterinarian, one Maine DMR representative, two

industry representatives (as nominated by Atlantic salmon producers), plus a non-voting chairperson 

selected by the four voting members. Each voting member pre-selects a voting proxy in the event 

they are unavailable at the time of a vote. See Part II C
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Negative site: an active site testing negative during the preceding two months for any ISAV genotype

while involved with active participation in an official surveillance program, including inspection by 

a veterinarian (See ISA Case Definition Category 1 in Table 2)

Net-pens: also called “net-pens” or “pens”; plastic or steel structures of differing sizes and shapes 

designed to contain variable numbers of fish

Non-pathogenic: not known to induce disease 

Pathogen: an agent (bacteria, viruses, fungi, parasites, etc.) capable of causing pathological changes 

in tissues. Not all pathogens cause clinical disease, and not all diseases are caused by pathogens

Pathogenic: known to induce disease 

Permit: a USDA APHIS Veterinary Services document entitled “Permit for Movement of Restricted 

Animals” (VS form 1-27) which allows for the bio-secure movement of fish from sites; may also refer 

to the vessel or fish transfer permit required by the Maine DMR

Processing plant: any facility where Atlantic salmon, or other ISAV-susceptible species, including 

products such as fillets used for value-added purposes, are taken for processing or rendering into a 

marketable product.

Producer: an individual or company raising Atlantic salmon, or other ISAV-susceptible species

Quarantine: enforced isolation to prevent the spread of infectious disease; See Part IV B

Restriction: no movement of live fish is allowed from the site, except for slaughter; and the 

implementation of a biosecurity program approved by the Maine DMR is required

RT-PCR: reverse-transcription polymerase chain reaction, a process where RNA is converted to 

complimentary DNA copy which is amplified in a cyclic fashion using a sequence-specific primer 

that binds to the gene target of a particular organism 

Sampler: an accredited veterinarian (or a person trained and designated by and under the direction 

of an accredited veterinarian) for the collection and submission of surveillance and diagnostic 

samples. 

Sea lice: copepod arthropods belonging to either the Lepeophtheirus or Caligus genera. 

Sequence: (Noun) The order of nucleotide bases in a DNA or RNA molecule; the order of amino 

acids in a protein molecule; the order of amino acids translated from a DNA or RNA molecule. 

(Verb) To determine the genetic code (nucleotides or amino acid translation) of a specific portion of 

the ISAV genome

Single Year-Class Site: an active site containing only one year-class of fish

Site: a specific area or facility where fish are raised 
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Site Identifier: a finfish aquaculture lease site identification number or code assigned by the DMR 

and unique for each site

Site veterinarian: a licensed and accredited veterinarian with fish health responsibility for one or 

more marine or freshwater sites where Atlantic salmon, or other ISAV-susceptible species, are 

cultured

Smolt: the stage at which Atlantic salmon are capable of physically and metabolically transforming 

to accommodate large osmotic differences as they move from a freshwater to a saltwater habitat

Surveillance: a program designed to detect or monitor the presence or absence of a pathogen or 

disease through periodic sampling and testing of fish within sites 

Transfer permit: a permit issued by the Maine DMR that authorizes the recipient to transfer live 

fish, fertilized eggs, or gametes to or from designated geographical area(s) in the coastal waters of 

Maine during a specified time period. A transfer permit may not be issued until the DMR has reviewed 

fish health inspection reports.

Vertical transmission: transfer of an infectious agent from one generation to another 

Virus Isolation: growth of a virus in a particular cell line; See Cell culture 

Year class: grouping of a population of fish of the same age/hatch year; and/or grouping by year of 

transfer to a marine site
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Part II. Administrative procedures

A. Supervision of the ISAV Control Program

The USDA APHIS VS District 1 Office for Surveillance, Prevention and Response Services (SPRS), 

located in the New England Area office in Sutton, MA, has administrative and supervisory 

responsibility for administering and managing all USDA, APHIS, VS, SPRS sector programs in New 

England, including the ISAV Control Program in Maine. The District 1 Director (DD) (or Assistant 

Director (AD), as delegated) will appoint a VS employee to oversee the ISAV Control Program,

designated as the Program Veterinarian.

ISAV Control Program Veterinarian: The Program Veterinarian is responsible for overall field 

management of the ISAV Control Program in Maine and reports directly to the District 1 AD. Major 

duties and responsibilities for this position include but are not limited to: assigning personnel as 

needed to carry out control program goals; collating surveillance reports from producers, site 

veterinarians, or the approved laboratories; resolving the accuracy of the respective surveillance 

reports; determining Site Categories; reviewing laboratory procedures; processing indemnity

payment; and meeting with industry on Program-related issues. The Program Veterinarian will, under 

conditions of confidentiality, have access to records of transfer permits and production information. 

USDA APHIS may utilize this information in epidemiological and economic investigations 

conducted by USDA staff or designees approved by the District 1 AD and for the generation of reports 

and information for utilization of the USDA APHIS ISA Technical Board in resolution of ISA 

incidents. The Program Veterinarian will be responsible for producing summaries of surveillance 

activities (as needed for significant changes in program or site status) for submission to: 1) the USDA 

APHIS VS District 1 AD (or delegate), 2) the Maine DMR, and 3) members of the USDA APHIS

ISA Technical Board.

The Program Veterinarian is responsible for management and administration of the ISAV Control 

Program. Major duties and responsibilities include coordinating and implementing all aspects of the 

ISAV Control Program (including these Standards) in Maine, and submitting reports to the District 1 

AD. To the extent feasible, the Program Veterinarian or Program staff will operate from an 

administrative base to be located in Maine and in the general vicinity of northeastern coastal salmon 

aquaculture operations. The Program Veterinarian will also facilitate communications with contact 

personnel at Maine DMR, Maine Department of Inland Fish and Wildlife (IF&W) , approved 
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laboratories, NVSL staff, APHIS VS aquaculture staff, New Brunswick Department of Agriculture, 

Aquaculture and Fisheries (NBDAAF) or other applicable parties (e.g. APHIS Legislative and Public 

Affairs personnel). Unless otherwise provided, all communications from the Program Veterinarian

(or staff) will take place under conditions of confidentiality to the fullest extent of federal law. The 

Program Veterinarian will develop and coordinate the dissemination of all necessary USDA APHIS

VS forms specific to the ISAV Control Program, and develop, supervise, coordinate and otherwise 

implement the provisions of these Standards. The Program Veterinarian will serve as liaison between 

USDA APHIS VS and any other parties for all actions to be undertaken involving the detection, 

control or elimination of ISAV- exposed, infected, or diseased fish under this program.

The Program Veterinarian will be a permanent member of the ISA Technical Board.

B. Access to sites

USDA APHIS VS personnel shall have access during normal hours of operations to all Atlantic 

salmon culture sites in order to carry out any and all aspects of these Standards.

C. ISA Technical Board

The ISA Technical Board membership is also defined in Part I. In short, there are 4 voting members, 

4 proxies, and a non-voting chairman. Other non-voting members may be appointed to the Board on 

an ad hoc or permanent basis by the APHIS SPRS District 1 AD or delegate at the suggestion of any 

member. Sub-committees may also be designated by the Board. A quorum for any issues requiring 

a vote will be all four voting representatives or their pre-selected proxies. The chairperson may only 

vote in the case of a tie and acts as a facilitator.

The purpose of the ISA Technical Board is to provide broad, balanced, and scientifically sound 

input to the District 1 DD or AD, the Program Veterinarian, the Maine DMR and/or the Maine 

Aquatic Animal Health Technical Committee. The Board provides recommendations regarding 

laboratory testing results, epidemiological data, audit reports, or other information pertinent to 

reported disease risks or conditions requiring action under the terms of this program. The Board 

will also periodically review the ISAV Control Program (including these Standards) to 

recommend any revisions or other changes. 

 
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D. Confidentiality

Confidentiality will be maintained to protect proprietary information submitted by the participants in 

the program. USDA APHIS may release summary economic information pertaining to 

indemnification (if applicable), including total expenditures and the total number of producers 

receiving indemnity. Personal information including individual names and producer-specific 

indemnity amounts will not be released. Additionally, forms used to submit ISA surveillance or 

diagnostic samples to the laboratory are not required to contain a site identifier. The submitting 

accredited veterinarian will retain copies of the lab submission forms with the site identifiers; and 

will submit a copy to the Program Veterinarian.

Part III. Disease Surveillance and Investigation

A. Basic requirements

An ongoing surveillance program to facilitate early detection of both pathogen and disease is essential 

for the effective prevention, management, and control of a wide variety of aquatic diseases, including 

ISA. The following basic requirements are mandatory for producers participating in the ISAV 

Control Program. Participation in the ISAV Surveillance Program for all active marine sites as 

detailed in this document is mandatory for any producer to become and remain eligible for 

indemnification by USDA APHIS in the event that 1) depopulation activities occur; and 2) funds 

become available. 

1. Any producer, with marine Atlantic salmon culture sites in Maine will establish and maintain 

a veterinary-client-patient relationship with an accredited veterinarian. This veterinarian will 

have responsibility for implementing all applicable provisions of the Standards at 

participating sites under his/her supervision.

2. Accredited veterinarians will conduct surveillance on behalf of their clients, and adhere to 

testing and reporting procedures for ISAV/ISA as described in these Standards.

3. Producers will develop and implement biosecurity protocols for use at marine sites,

processing plants (if applicable), and vessels engaged in aquaculture operations throughout 

Maine (See Appendix A). These biosecurity protocols will be available to the Program 

Veterinarian.
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4. Biosecurity audits of active sites and vessels shall be conducted at the frequency required by

the Maine DMR Chapter 24.21 regulations. These audits will be completed by trained and 

experienced personnel as assigned by the Program Veterinarian.

5. Producers must submit an Integrated Pest Management Plan for the control of sea lice on 

salmonids at the time of enrollment into the ISA Program. Studies have indicated that 

Lepeophtheirus sea lice may be a vector capable of transmitting ISAV to Atlantic salmon 

(Nylund et al. 1994).

B. Surveillance Requirements

Minimum surveillance activities will involve onsite inspection by an accredited veterinarian, or 

technician under his/her supervision, as well as collection of appropriate samples for ISAV assays. In 

addition, USDA APHIS personnel under the direction of the Program Veterinarian or the District 1 

AD (or delegate) may collect samples as needed as part of this surveillance. The schedule of 

surveillance inspections depends upon each site’s specified ISAV Control Program Site Category 

(See Table 2 for Category Definitions). This schedule will be as follows:

Monthly: Any sites meeting the criteria for ISAV Control Program Site Category 1.

Biweekly: Sites meeting the criteria for ISAV Control Program Site Category 2, as well as any

other marine sites that are considered by the ISA Technical Board as potentially exposed to a 

Category 2-5 site. Note: if a detection of an HPR-deleted genotype of ISAV has been made in 

the lower end of New Brunswick’s ABMA1 (around Deer Island or Campobello Island), sampling 

of all active marine sites in Cobscook and Passamaquoddy Bays may, at the discretion of the ISA 

Technical Board, increase to biweekly. 

Weekly: Sites meeting the criteria for ISAV Control Program Site Categories 3 thru 5.

As needed: the inspection schedule may be modified to resolve issues of ISA site status. Sampling 

frequency may also be adjusted at the discretion of the Program Veterinarian and/or the ISA 

Technical Board. 

Note: New marine sites, Site Category 6 sites, or inactive marine sites returning to active status

must initiate surveillance activities within 6 weeks of first introduction of salmonids to the site.
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1. Surveillance inspections shall consist of visual inspections by an accredited veterinarian, of 

all net-pens on a site, review of weekly and/or most recent mortality figures, and collection of 

diagnostic samples for testing as described in these Standards. Inspection reports and other 

documents showing surveillance activities must be maintained and made available to the 

Program Veterinarian upon request.

2. The accredited site veterinarian will be responsible for personally conducting a minimum of 

one monthly veterinary surveillance inspection of each respective site for which she/he has 

fish health responsibility. This should coincide with a scheduled dive to collect mortalities. 

More frequent surveillance requirements should include veterinary inspections as defined in 

#1 above. 

3. USDA-authorized personnel may also conduct sampling as necessary to comply with these 

Standards. This sampling option will be coordinated by the Program Veterinarian after 

consultation with the producer and accredited veterinarian.

4. When completion of harvest of all fish at a site is anticipated within the next month, a waiver 

of veterinary surveillance inspections may be obtained on a case by case basis from the 

Program Veterinarian.

C. Sample specifications

Active sites will be sampled as follows: 

1. Appropriate numbers of moribund or recently dead fish will be collected per scheduled veterinary 

surveillance inspection. A maximum of 10 targeted fish per routine monthly site visit should be 

collected whenever possible or a minimum of 3 within a two month period. At the discretion of 

the site veterinarian, additional samples may be submitted.

2. Chain-of-custody documentation must accompany the submitted surveillance samples. A copy 

will be forwarded by the submitter to the Program Veterinarian.

3. Samples will be tested in accordance with diagnostic testing protocols in Part III D and by USDA 

APHIS-approved laboratories (See Part III F). 
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4. Sample specifications: Table 1 below lists sample specifications for the ISA assays to be 

performed.

Table 1: Sample Specifications for ISAV Control Program Approved Assays

TEST Assay Pool Tissue Collecting vessel/

Preservative/media

RT-PCR Single fish 0.25 cm3 mid kidney 2 ml tube/RNA

Later

IFAT Single fish 2-3 Mid-kidney impressions Frosted end slide

Virus 

Isolation 

(cell culture)

Up to 5 fish per 

pool per net-pen

Kidney, spleen, heart Specimen cup/approved 

media

D. Diagnostic Tests and Diagnostic Testing Standards

The official diagnostic tests for the ISAV Control Program include the following: 

a) RT-PCR

b) IFAT

c) Virus Isolation (cell culture)

d) Sequence

e) Gross Pathology

f) Other approved tests

All official tests for ISAV will be performed by an approved laboratory, except for gross pathology 

which will be evaluated by the accredited veterinarian or USDA-authorized sampler. The laboratory 

will use ISAV diagnostic test procedures that have been reviewed and approved by APHIS’ National 

Veterinary Services Laboratories.

Surveillance of all sites will utilize RT-PCR as the primary screening diagnostic test, and IFAT as a 

secondary assay. IFAT impression smears will be obtained from all sites and will be acetone-fixed 

and archived at the receiving laboratory. IFAT slides corresponding to any tissue sample testing 

positive by RT-PCR will be subsequently processed and evaluated. 

Tissue samples for virus isolation should be collected during inspections of a Category 2 or higher 

status site, or at the discretion of the accredited veterinarian, the Program Veterinarian and/or the ISA 
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Technical Board. All suspect and infected tissue samples and positive supernatants will be archived 

(for at least a 1 year) by the receiving laboratory after testing has been completed. 

A positive RT-PCR is considered suspect, and requires immediate notification of the ISA Program 

Veterinarian, Maine DMR the accredited veterinarian and the National Veterinary Services 

Laboratories (NVSL), the APHIS VS reference laboratory. Tissue samples of initial suspect cases 

will be sent to NVSL from the originating laboratory within 24 hours of suspect results for official 

confirmatory testing. RT-PCR assays will be sequenced as part of this testing at NVSL. 

Resolution of inconclusive or conflicting diagnostic tests will be determined by the USDA APHIS

ISAV Control Program Veterinarian or the District 1 DD or AD (or delegate) following consultation 

with the applicable accredited veterinarian, the approved laboratory, and NVSL. If a sample or site 

status remains unresolved after consultation then referral to the ISA Technical Board is required. 

Issues surrounding conflicting or otherwise questionable results may be resolved through the 

following (independently or in combination):

1. Additional tests performed on archived samples by the approved laboratory.

2. Additional tests on archived samples performed by the NVSL

3. Collection of additional samples from the site or net-pen and with testing by the approved 

laboratory and/or NVSL.

4. Increased sampling frequency from the net-pen in question, additional net-pens, or netpen site.

5. Consultation with the ISA Technical Board.

The Program Veterinarian and District 1 AD (or delegate) shall consider recommendations made by 

the ISA Technical Board and will make final determination (in conjunction with the Maine DMR) on 

all ISAV Control Program issues.

E. Biosecurity audits 

All marine sites and vessels will be subject to third party biosecurity audits at least once a year, in 

addition to any internal audits. Records shall be kept of these audits, including recommendations for 

improvement and any corrective steps taken to address deficiencies.
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1. Marine sites that are classified as ISAV Control Program Site Category 2-5 shall be subject 

to more frequent biosecurity audits.

2. If a processing plant is receiving fish from Category 2-5 sites, they may be subject to periodic 

biosecurity audits.

F. Reporting 

Accurate and timely reporting, of all activities related to this program, is essential. Reports and 

documents required include, but are not limited to, laboratory test reports; net-pen/site depopulation

reports; cleaning and disinfection certificates; fish inventory documents; and permits. 

All surveillance reports and actions regarding ISA control measures must reference the site 

identification code and name. All surveillance documents, laboratory reports, and other documents 

as required will be forwarded to the Program Veterinarian. A flow chart reflecting the reporting 

mechanism is provided in Appendix D. Reporting responsibilities and requirements are as follows:

Accredited Veterinarians: Accredited veterinarians shall, in accordance with Title 9 Code of 

Federal Regulations Part 161.3, report to the Program Veterinarian and the Maine DMR any 

suspected or confirmed cases of ISA within 24 hours of learning of these test results or diagnosis. 

Accredited veterinarians shall submit all diagnostic samples for ISA to an approved laboratory in 

accordance with instructions provided by these Standards, the Program Veterinarian, or the District 1 

AD (or delegate), and shall follow any and all procedures as instructed by them. Accredited 

veterinarians shall use either USDA APHIS Specimen Submission Form (VS form 10-4) or other 

approved form developed by the Program Veterinarian (such as the included Sample Submission 

Chain-of-custody form). 

Approved Laboratories: The approved laboratory shall report results of surveillance screening tests 

to the Program Veterinarian, the District 1 AD (and/or delegate), the Maine DMR and the submitting

accredited veterinarian within 10 days of sample receipt. In the case of a suspect or positive result, 

those listed above will be notified within 24 hours of test completion.

The laboratory shall report all test results for ISAV sample collections within 24 hours of testing 

completion to the Program Veterinarian, the District 1 AD (or delegate), the Maine DMR, and to the 

submitting accredited veterinarian. If viral culture was included in the sampling, the final report of 
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sample results must be submitted to the same entities as above within 30 days from the date of sample 

receipt. A flow chart reflecting the reporting mechanism is provided in Appendix D..

Part IV. Standards for Disease Control Actions and Management

A. ISAV Control Program Categories 

ISA Program Categories and their descriptions are found in Table 2 below. The purpose of the 

classification system is to provide the Program Veterinarian and Technical Board more information 

for sites so that further evaluation, epidemiological investigation, and testing can be designed, 

ordered, and initiated as appropriate. 

Table 2: ISAV Control Program Categories and Description

Category Category Description

Category 1

(presumed negative)

HPR-deleted ISAV has not been detected within at least the previous two 

months in a net-pen or site participating in active ISAV monthly 

surveillance testing; considered negative for ISA.

Category 2

(suspect)

Any variant of ISAV has been detected in a net-pen or site by at least one 

diagnostic test in at least one fish; considered suspect and needing further 

evaluation within 7 days.

Category 3 (infected)

ISAV has been detected in at least two fish from a single net-pen by at 

least two official diagnostic tests, one of which includes an HPR-deleted 

sequence result. For subsequent detections in other (previously negative) 

net-pens at the same site, a net-pen may also be designated Category 3 

based on one fish positive by two tests and one fish positive by virus 

isolation (from a different tissue pool) – both fish must have one HPRdeleted sequence result.

Category 4

(diseased)

As for Category 3 above, plus clinical disease is present (as diagnosed by 

an accredited veterinarian).

Category 5

(diseased)

As for Category 4 above, plus mortality consistent with clinical ISA is 

present at the average rate of 0.05% per net-pen population per day over 

one week.

Category 6 Net-pen or site previously classified as Category 2 through 5 has been 

fallowed.

Net-pens and sites, owned by producers participating in the ISAV Control Program, will be 

categorized according to the surveillance test results criteria included in Table 2 above. Net-pens and

sites will be categorized or re-categorized as often as necessary to reflect testing results and 
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management actions taken under this section, or taken at the discretion of individual producer policy, 

if that policy does not conflict with the intent of these Standards. 

The site will be designated with the highest net-pen Category number it contains. For example, if it 

contains both a Category 2 and 3 net-pen, it will be designated as Category 3 until that net-pen is 

removed. If a site contains a single Category 3 or higher net-pen, once the fish are removed from that 

net-pen, the site will revert to Category 2, and undergo biweekly testing until there have been 2 

months of negative testing results.

Actions to be taken will depend upon site Category and are as follows: 

1. ISA Program Category 1: net-pens/sites will continue to conduct surveillance at monthly 

intervals as detailed in Part III B (Surveillance Requirements). 

2. ISA Program Category 2: net-pens/sites will be required to undergo follow-up sampling, 

including individual sample virus isolation, within 7 days of the report of a positive test result in 

order to ascertain a more precise program category if possible; except in the case of an HPR0 

finding. An HPR0 finding will immediately reclassify the net-pen/site as Category 1. Follow-up 

samples should be collected from the suspect net-pen whenever possible; if an adequate number 

of moribund fish are not available from that net-pen, samples may be collected from other netpens on the site. Based on the particular situation: : 1) the Program Veterinarian will notify the 

District 1 AD (or delegate); 2) the ISA Technical Board may be convened; 3) additional 

epidemiological information may be requested from the producer; and/or 4) consultation with 

USDA APHIS VS NVSL or APHIS headquarters staff may occur. If sequencing results in HPR0,

Category 2 net-pens/sites will revert to Category 1. In all other cases, Category 2 net-pens/sites 

will revert to Category 1 after four consecutive negative biweekly veterinary surveillance 

inspections and/or after consensus by an ISA Technical Board vote in consultation with the 

Program Veterinarian.

3. ISA Program Site Category 3, 4 or 5: When net-pens are declared infected or diseased by the 

Program Veterinarian, depopulation orders will come from the Maine DMR per their Chapter 24

regulations. A site- specific action plan for the control and management of the disease will be 

developed by the producer in consultation with the Program Veterinarian and ISA Technical 
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Board. The Program Veterinarian may request inventory, mortality data, etc. from the affected 

site.

4. Alternatively or simultaneously, the Maine Commissioner of Marine Resources or a delegate may 

put any site falling into Category 2 through 5 under restriction or quarantine, if it is felt such action 

is necessary to prevent the spread of disease or disease agent. For sites under restriction, no 

additional fish may be transferred to or from the site unless specifically authorized in writing by

the District 1 AD (or delegate) and DMR. The site accredited veterinarian will also be informed 

of any restriction or quarantine measures. 

5. The Program Veterinarian will serve as liaison between USDA APHIS VS and all other parties 

for all actions to be undertaken involving the depopulation of any stock. 

B. Quarantines

Quarantines will be issued by the regulatory authority of the Commissioner of the Maine DMR. 

Quarantines will be released only after fish have been moved in compliance with program standards 

and all nets, pen equipment, and other fomites and materials have been properly cleaned and 

disinfected. Fish or population cohorts considered exposed to ISAV as a result of interactive 

epidemiological factors may be considered for quarantine depending on the particular circumstances 

pertaining to each outbreak. Conditions of quarantine include: 1) the implementation of a biosecurity

plan is required to be approved by the Maine DMR; 2) visitation is limited by the biosecurity plan; 3) 

disposition of all quarantined fish must be done in a manner approved by the Program Veterinarian

and the Maine DMR; and 4) no equipment or vessels are to move between the quarantined site and 

other sites unless authorized by the Program Veterinarian and Maine DMR. 

C. Indemnity 

As stipulated in Title 9 CFR Part 53.10, and when funding is available, indemnity payments will be 

made to producers complying with the Standards, for fish destroyed due to ISA. These may include 

ISAV-infected as well as ISAV-exposed fish. The District 1 AD (or delegate) or Program 

Veterinarian will make final determination as to the Category of the site and approval of indemnity 

payments to producers. A schedule of payments will be coordinated by the Program Veterinarian or 

the District 1 AD (or delegate).
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Upon determination that fish are to be depopulated an indemnity estimate worksheet will be prepared 

and signed by the producer or producer’s representative and the Program Veterinarian. 

In the case of non-marketable fish, indemnity will be paid on a per-fish basis using stocking inventory 

documents, mortality figures, and other information available. Marketable fish will be paid also based 

on a per-fish basis using the established indemnity scale with the USDA paying any difference 

between individual fish salvage proceeds and the established per-fish indemnity value. 

The USDA APHIS VS Appraisal and Indemnity Claim (VS form 1-23) is the official document to 

process all indemnity claims for this program. Indemnity payments will be executed only after the 

site is properly cleaned and disinfected in accordance with Part IV F and Appendix A of these 

Standards.

Indemnity payments are based on the availability of funds approved for that purpose.

D. Depopulation

All depopulation orders will arise from the regulatory authority of the Commissioner of the Maine 

DMR. Depopulation may be ordered based on net-pen or site Program Category or as a result of 

consultation with the Program Veterinarian or District 1 AD (or delegate), and/or recommendations 

from the ISA Technical Board. Additional discussions may take place among those parties in case of 

disagreements, or if clarification is desired. 

Any depopulation ordered by the Maine DMR must be complete within the time frame set by the 

order. If unusual circumstances such as large-scale depopulation or weather-related factors intervene, 

a request for an extension of the depopulation completion timeline must be submitted in writing to 

the Commissioner of the Maine DMR before the original deadline has passed. Depopulation must 

be accomplished minimizing exposure of all other fish at the site or in adjoining waters, and in 

accordance with Appendix A of this document. Standards for fish harvesting, transportation, and 

processing are also included in Appendix A. Depopulated fish may be moved to composting sites, 

landfills, or fish processing plants only after meeting all applicable federal and state regulatory

criteria. All methods of harvest or transport for disposal shall comply with either the stipulations of 

these Standards, Maine MRSA Chapter 24.21 and/or any pertinent DMR Emergency regulations. 

Category 3, 4 or 5 fish (infected and diseased) that are harvested by live-haul will be transported to 

processing plants in a manner that does not allow untreated contained water to be exchanged with or 
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otherwise contact the environment during transport. The Program Veterinarian or other APHIS 

personnel appointed by the District 1 AD will oversee the depopulation procedures for as many units 

as may be practical.

E. Permitting

All fish, nets, equipment, and other fomites capable of transmitting ISAV must be permitted for 

removal from all Category 2 and higher sites. Permitting will be coordinated between USDA APHIS 

VS and the Maine DMR to allow movement of fish to fish processing plants, fish composting

facilities, rendering, or landfill sites. 

F. Cleaning and Disinfection

If any net-pen or site depopulation is ordered as a result of ISA surveillance, cleaning and disinfection 

must occur after any complete removal of fish from a site. The level, specification, and schedule for 

cleaning and disinfection after any depopulation is ordered for any net-pen or site will follow 

established guidelines (See Appendix A). The ISA Technical Board may be convened to review issues 

surrounding cleaning and disinfection and make recommendations to the Program Veterinarian. 

Site-specific cleaning and disinfection programs shall be developed and implemented at all finfish 

culture sites, and should include at least the following elements: 

 All site personnel and management shall be trained in proper disinfection procedures.

 Documentation shall be maintained in order to verify consistent implementation and 

identify employees responsible for their implementation.

 Assure that contractors or other visitors understand and follow disinfection guidelines and 

all other relevant protocols.

G. Fallowing

Fallowing must occur following removal of any population of fish, whether infected or not. The 

minimum fallow time is 30 days. In the absence of disease, fallowing time begins upon fish removal.

In the case of pathogenic ISAV, fallowing time period begins only upon completion of all cleaning 

and disinfection procedures of net-pens, pens, equipment, and other fomites as required. Fallows are 

to be synchronized with neighboring sites in restricted Fish Health Zones. The Maine DMR has final 

determination of fallow duration.
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salmon anaemia virus (ISAV) in Chilean Atlantic salmon (Salmo salar) aquaculture: emergence of 

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P.J., Page, F.H. 2007a. Hydrographics and the timing of infectious salmon anemia outbreaks among 

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Gustafson, L., Antognoli, M., Lara Fica, M., Ibarra, R., Mancilla, J., Sandoval del Valle, O., Enriquez Sais, 

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(ISAV) isolated form the ISA disease outbreaks in Chile diverged from ISAV isolates from Norway 

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Virology Journal 6, 88-104.

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anemia visu pathogenesis in fish. Journal of General Virology, 87: 2645-2652.

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Jarpa, M., Larroquete, G., Avendano, F., Lara, M., Gallardo, A. 2009. Infectious salmon 

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S, Endresen, C., Biering, E. 2001a Cloning and identification of the infectious salmon anaemia 

virus haemagglutinin. Journal of General Virology 82, 1757-1765.

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infectious salmon anaemia (ISA) outbreaks in Norway 2003-2005. Veterinaerinstituttets rappportserie 

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salmon gill epithelial cells. Virology Journal 10.
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APPENDIX A: Fish Health, Biosecurity, and Cleaning & Disinfection

These guidelines are intended to reduce the risk of the introduction and spread of infectious diseases (including 

but not limited to ISA) at Atlantic salmon production sites. Each producer shall develop company and sitespecific protocols addressing at a minimum the types of activities that can impact fish health or biosecurity at 

production sites, 

Effective Disinfectants

The effectiveness of most disinfectants is greatly reduced by organic material. All objects must be 

thoroughly cleaned to remove organic materials prior to disinfecting. 

The following is a list of disinfectants that are effective against ISAV:

 sodium hypochlorite (100mg/l free chlorine for minimum of 10 minutes);

 iodophor (100ppm for 10 minutes or 250ppm for a few seconds);

 formaldehyde (1.0% for 16 hours);

 formic acid (pH <4 for 24 hours);

 sodium hydroxide (pH > 12 for 7 hours);

 heat (>55C for > 5 minutes);

 ozone (8 mg/l/min for three minutes – corresponding to a Redox potential of 600-750mV);

 UV radiation (120mJ/cm2)

 Virkon® S (2% solution/10 minutes; followed by water rinse)

 Sodium thiosulfate can be used to neutralize chlorine or iodine -based disinfectants

Note: The choice of a particular disinfectant should be based on efficacy in a particular application

Cleaning & Disinfection Levels

Three levels of vessel and equipment disinfection are to be used. The minimum level of disinfection required 

is determined by the operational circumstances as defined in the Table below.

OPERATIONAL CIRCUMSTANCES DISINFECTION LEVEL

Travel from any Category 1 site to any Category 1 – 5 site 1

Travel from Category 2 site to any other Category 2 – 5 site 1

Travel from Category 3 – 5 site to any Category 1 or 2 site 2 or 3*

Travel from Category 3 - 5 site to any other Category 3 through 5 site 1

Travel from a wharf servicing of vessels coming from Category 2-5

to Category 1

2

Travel from Category 3-5 fish health zone to any Category 1 or 2 fish 

health zone 2 or 3*

* As determined by DMR and ISA Program Veterinarian
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Level 1 Cleaning and Disinfection:

 Prior to use, ensure disinfectants are approved for discharge under the producer’s Maine DEP 

permit

 Establish a “clear deck”.

 Any ropes, straps or equipment removed during the process of establishing a “clear deck” should 

be cleaned and disinfected prior to stowing.

 Thoroughly clean all surfaces from the water line up of any organic material or inorganic 

particulate matter.

 Special efforts should be made to remove any fats or oils.

 Coat and scrub all surfaces using an approved disinfectant allow appropriate contact time.

 A low pressure applicator may be used to apply disinfectants.

 A high pressure washer may be used for cleaning and a steam pressure washer may be used for 

both cleaning and disinfection 

 Fill out and sign cleaning and disinfection log.

Level 2 Cleaning and Disinfection:

Perform all Level 1 cleaning and disinfection protocols. In addition, perform the following Level 2 

protocols:

 Internally inspect, cleanse, and disinfect any fish pumps and vessel wells.

 Ensure that disinfectants are repeatedly cycled through all pumps, pipes, hoses and/or valves that 

may have contacted fish, fish water or blood-water.

Level 3 Cleaning and Disinfection:

 Perform all Level 2 cleaning and disinfection protocols. In addition, slip or careen the vessel;

clean, scrape, wash, and disinfect the hull.

 If it is not possible to careen the vessel, producers should discuss alternatives with the DMR and 

ISA Program Veterinarian.

Cleaning and Disinfection Protocols for Specific Areas of Operation:

A. Vessels & Wharves

 Vessel traffic between marine sites and between wharfs should be minimized.

 Vessel traffic between fish health zones should be minimized.

 All vessels should maintain a disinfection log that documents the cleaning and disinfection 

procedures used on the vessel.

 Disinfection logs for site-specific skiffs can be maintained on the farm site rather than carried onboard.

 At a minimum, the disinfection log should identify what specific areas of the vessel were cleaned 

and disinfected; the cleaning, and disinfectant agents used, the date of such procedures, and the 

signature of the responsible employee or vessel captain.

o All vessels shall have their hulls cleaned and scraped regularly, at least annually, to 

minimize bio-fouling.

o All vessels carrying live or dead fish must clean and disinfect all areas of the vessel from 

the waterline up before and after each trip.

o Particular attention should be paid to areas of the vessel and fish handling equipment that 

come in direct contact with fish or water fish have been in.
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o All vessels carrying live or dead fish must fill out their disinfection log after each day they 

have carried fish.

o When cleaning and disinfecting any vessel, particular attention should be paid to areas that 

are difficult to access. Wherever possible, vessel and equipment design should minimize 

such areas. 

o Vessels operating in fish health zones with ISAV Control Program Category 2-6 sites must 

have their hulls cleaned and scraped twice annually or once annually and use an effective 

anti-foulant hull paint.

 All vessels are subject to third party biosecurity audits per DMR Chapter 24 regulations.

 At the wharves used to access sites, boom truck operators and loading crews must avoid all spillage. 

If spillage does occur, every effort should be made to contain the spillage, clean and disinfect the 

area.

 Disinfect vessel and all gear after leaving the wharf.

 Disinfect boom truck and all gear including straps after loading/unloading the vessel.

B. Personnel & General Equipment

 Limit traffic to sites and require that everyone going to the site properly disinfects on the wharf or 

vessel, and that everyone leaving the site properly disinfects on the vessel.

 All sites must maintain a visitor log.

 All people traveling to a site must wear footgear that can be disinfected by stepping into a footbath.

 Footbaths must be present, and properly maintained, throughout the site and on vessels.

 Everyone who comes in contact with dead fish, moribund fish, processed fish or fish parts, and 

blood-water shall properly clean and disinfect their gear and themselves before leaving the 

site/vessel.

 Keep employees and their gear, site-specific when possible. Proper disinfection and air-drying of 

all gear must be enforced between sites when this is not possible. Properly clean and disinfect all 

equipment after each use - 

 Do not use wooden equipment, vessels or barges - they cannot be properly disinfected. Wooden 

pallets are permissible for one time use only, such as feed delivery.

 Minimize sharing of equipment between sites.

C. Containment Nets & Pens

 When replacing nets, they should be cleaned on land when possible.

 Nets and pens must be cleaned of all organic material before disinfecting.

 All nets from Category 2 through 5 sites will be taken to land for cleaning and disinfection. 

 Nets from Category 2 through 5 sites being transported to shore will be contained in a manner which 

prevents the loss or spillage of organic matter.

 Care should be taken to ensure that the cleaning/disinfecting procedure used for nets does not 

adversely affect the breaking strength or anti-foulant treatment (if applicable).

D. Divers and diving gear

 Properly disinfect diving gear before first net-pen, between net-pens, and after last net-pen.

 Dive the youngest fish first when diving multiple sites in a day.

 Dive net-pens with elevated mortality last; if there are suspect and/or positive net-pens, dive these 

last and disinfect between diving on net-pens by full immersion.

 All diver equipment should be site-specific, when possible. If a diver must dive more than one site 

using the same gear, it is imperative that all gear is disinfected between sites. Ideally, gear should 

be disinfected after the last net-pen at the first site and allowed to air dry. If this is not practical, 
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gear should have at least a 10 minute contact time with iodophor solution before being used 

at the second site.

 Diver attendants shall wear designated site-specific and mort-specific rain gear. This gear must be 

properly cleaned and disinfected after each use. Boots shall be properly disinfected after each mort 

dive.

 Disinfect net-pen handrails and net areas above the water line that mort bags and divers come in 

contact with.

 If possible, a separate site-specific vessel (steel or fiberglass construction) should be dedicated to 

diving only.

 Mortalities should be removed from the site after each dive, or as soon as possible.

 During dives, when possible, separate mort bags should be used for each net-pen; otherwise, bags 

should be alternated between net-pens so that one bag will soak in disinfectant for 10 minutes or 

more.

 If the mortality level meets or exceeds 0.05% per day, mortalities are to be removed daily from netpens or sites. At this level, each pen must have its own mort bag and any weak fish should be dipped 

from the surface.

E. Dead fish & Blood-water collection, storage, and disposal

 Dead fish, moribund fish or blood-water shall not be released into the marine environment.

 All attempts should be made to prevent leakage and spills during harvest and transport.

 Collect all dead fish at least once weekly, weather permitting. More frequent collection should 

occur if mort numbers are elevated.

 Use only mort containers in good condition, never cracked and leaky ones.

 Use plastic liners in mort containers. Cover mort containers with properly fitting lids.

 All mortality-related equipment should be kept separate and away from other equipment. 

 All mortalities are to be taken ashore and disposed of at a Maine Department of Environmental 

Protection (DEP) approved facility. 

 Use mort-specific equipment for storage and transport of dead fish. Mark containers “morts only”.

 If possible, mort containers should be site specific.

 Do not store mortalities on site, if possible. If morts are stored on site at all, store mort containers 

away from feed. Place a footbath with disinfectant in the immediate vicinity of the mort containers.

 Empty mort containers as soon as possible, preferably after each mort dive.

 Disinfect area beneath and surrounding mort containers whenever it is removed for disposal of 

dead fish. Promptly clean and disinfect any spillage from mort containers.

 Clean and sanitize mort containers before returning to a site. This is best done immediately after 

disposal.

F. Broodstock & Eggs

Although the best current scientific information indicates the risk of vertical transmission for ISA is 

low, the following guidelines are recommended as good husbandry practices designed to reduce the 

potential risk of vertical transmission in general.

 Lethal sampling and disease testing should be conducted on all broodstock.

 No gametes should be used from clinically infected broodstock sites.

 No gametes should be used from individual broodstock that test confirmed positive for any 

pathogen of regulatory concern. Refer to DMR Chapter 24 regulations.

 Eggs and juvenile stages at fresh water facilities must never share the same facility area or water 

mass with broodstock moved from marine sites.

 Any movement of broodstock or eggs must be permitted under DMR Chapter 24 regulations. 
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APPENDIX B: Guidance for laboratories and VS personnel in the 

event infectious salmon anemia virus (ISAV) is detected at a Maine 

Atlantic salmon production facility

1. Within 24 hours of any ISAV detection:

a. The diagnostic laboratory will notify the sample submitter, facility accredited 

veterinarian (if different from submitter), and the APHIS ISAV Program 

Veterinarian. This should occur before any additional testing is initiated at the 

receiving diagnostic laboratory. 

i. The ISAV Program Veterinarian will notify the VS District 1 AD and Fish 

Biologist of the detection. 

ii. The District 1 AD will notify the VS District 1 DD and the APHIS AQ 

Program Leader. 

 In all cases, confirmation of receipt of notification is requested or to 

provide contact for alternate representative.

iii. The ISAV Program Veterinarian or fish biologist will notify Maine DMR 

contact. The State may enact any ‘hold’ order they deem necessary pending 

further information.

b. The diagnostic laboratory will notify the NVSL of the positive detection and ship 

appropriate samples for confirmation. This should occur before any additional 

testing is initiated at the diagnostic lab. 

In general:

i. Priority 2 status will be assigned for cases of PCR + findings in healthy 

animals [no mortality or morbidity associated with case] found on routine 

surveillance samples

ii. Priority 1 status will be assigned:

 For cases of PCR + findings in animals showing clinical signs 

consistent with infection with ISAV and/or high mortality

 For samples from animals showing clinical signs consistent with 

infection with ISAV and/or high mortality, sent directly from the 

field and not previously tested

 When ISAV HPR-deleted is suspected in in apparently healthy 

animals [no mortality or morbidity associated with case]

2. The ISAV detection information will be entered into the National Aquatic Animal Instance 

of SCS (Surveillance Collaboration Services) database and EMRS (Emergency 

Management Response System), along with any relevant attachments. 

a. In EMRS, an FAD investigation will be initiated and an FAD # assigned

3. If the initial detection of ISAV is not confirmed at the NVSL, meaning the NVSL reports 

negative findings for ISAV in the submitted sample(s), the EMRS and SCS databases will 

be updated and the EMRS investigation will be closed out (new information may cause the 
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case to be re-opened).

4. If ISAV HPR0 is confirmed at the NVSL:

a. All those mentioned above will be immediately notified of confirmation.

b. The Aquaculture Program Leader, or a representative, will notify the VS 

international health standards services group for discussion and a decision will be 

made on reporting to the OIE.

i. Generally HPR0 detections are included in the APHIS OIE 6 month report. 

This report is simply that it occurred during the 6 month reporting time 

frame. 

c. The ISA Technical Board will be notified by the ISAV Program Veterinarian or 

Fish Biologist. The FAD investigation will be updated and closed out in EMRS.

5. If ISAV HPR-deleted is confirmed at the NVSL, in even a single fish,

a. All those mentioned above will be immediately notified of confirmation 

b. The Aquaculture Program Leader, or a representative, will notify the VS 

international health standards services group for discussion and a decision will be 

made on reporting to the OIE.

i. The Maine DMR will notify other State agencies they deem applicable. The 

State may enact any ‘hold’ order they deem necessary pending further 

information.

c. Follow-up samples will be collected by the facility Accredited Veterinarian or other 

appropriate designee and duplicate samples sent to both the NVSL and diagnostic 

laboratory.

i. For marine farms, within 7 days of the confirmation notification (as per the 

Program Standards)

ii. For freshwater facilities, within 3 days of the confirmation notification 

d. The ISA Technical Board will convene to discuss next steps. For marine farms, the 

Program Standard protocols will be followed. For freshwater facilities, similar 

protocols may be discussed and decided upon. 

6. The incident will be updated in EMRS as an investigation (non-confirmed HPR-deleted) or 

FAD (confirmed HPR-deleted). It will be closed out once the incident has been resolved. 
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APPENDIX C: ISAV Control Program Contacts 

USDA APHIS VS SPRS:

Thomas McKenna, DVM

District 1 Director

160 Worcester-Providence Rd. 

Sutton Square Plaza, Suite 20

Sutton, MA 01590

Ph: (508) 363-2290 Fax: (508) 363-2272 Cell: (508) 887-3421

Email: thomas.s.mckenna@aphis.usda.gov

Koren Custer, DVM, MPH

District 1 Assistant Director

160 Worcester-Providence Turnpike 

Sutton Square Plaza, Suite 20

Sutton, MA 01590

Ph: (508) 363-2290 Fax: (508) 363-2272 Cell: (774) 276-1985

Email: koren.m.custer@aphis.usda.gov

Chip Ridky, DVM

ISAV Control Program Veterinarian

28 State House Station

August, ME 04333

Ph: (207) 287-7632 Fax: (207) 622-6848 Cell: (207) 837-2518

Email: chip.ridky@aphis.usda.gov

Maine Department of Marine Resources:

Marcy L. Nelson

Scientist, Division of Aquaculture

194 McKown Point Road, PO Box 8

West Boothbay Harbor, ME 04575

Ph: (207) 633-9502 Fax: (207) 633-9579

Email: marcy.nelson@maine.gov

Maine Department of Agriculture, Food and Rural Resources:

Michele Walsh, DVM State Veterinarian

28 State House Station

Augusta, ME 04333

Ph: (207) 287-3701 Fax: (207) 287-7548 Cell: (207) 592-4593

Email: michele.walsh@maine.gov

Maine Department of Inland Fish & Wildlife:

TBD

David R. Russell, Fish Pathologist

Maine Department of Inland Fisheries & Wildlife

Division of Fisheries and Hatcheries

Fish Health Laboratory

81 Hatchery Road

Augusta Maine 04330

Ph: (207) 287-2813

Email: david.russell@maine.gov 
Navigation Notes

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Kennebec River Biosciences, Inc.

William Keleher

President/CEO

41 Main Street

Richmond, ME 04357

Ph: (207) 844-5452 Fax: (207) 737-4505 Cell: (207) 841-1835

Email: wkeleher@kennebecbio.com

Cem Giray

CSO

41 Main Street

Richmond, ME 04357

Ph: (207) 844-5454 Fax: (207) 737-4505 Cell: (207) 841-1836

Email: cemgiray@kennebecbio.com

National Veterinary Services Laboratories:

Beverly J. Schmitt, DVM

Director

1920 Dayton Ave.

Ames, IA 50010

Ph: (515) 337-7601 Fax: (515) 663-7397

Email: beverly.j.schmitt@aphis.usda.gov

Janet Warg, MS

Microbiologist

1920 Dayton Ave.

Ames, IA 50010

Ph: (515) 337-7551 Fax: (515) 337-7348

Email: janet.v.warg@aphis.usda.gov

Maine Aquaculture Association

Sebastian Belle, Director

Box 148

Hallowell, ME 04347

Ph: (207) 622-0136 Fax: (207) 622-0576

Email: maineaqua@aol.com

Veterinary Contacts by Company

Cooke Aquaculture 

Leighanne Hawkins, DVM

61 Wallace Cove Rd.

Blacks Harbour, NB E5H 1G9

Canada

Ph: (506) 456-6637 Fax: (506) 755-2386 Cell: (506) 754-2387

E-mail: leighanne.hawkins@cookeaqua.com

Amy Canam, DVM

61 Wallace Cove Rd.

Blacks Harbour, NB E5H 1G9

Canada

Ph: (506) 456-6637 Fax: (506) 755-2386 Cell: (506) 456-6863

E-mail: amy.canam@cookeaqua.com
Navigation Notes

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Salmon Producers – Maine Contacts

Cooke Aquaculture

Dave Morang

Maine Saltwater Production Veterinarian

40 Barron Rd

Eastport, ME 04631

Ph: (207) 853-6081 Fax: (207) 853-6056 Cell: (207) 214-6047

Email: dave.morang@cookeaqua.com

Jennifer Robinson

Compliance Officer

40 Barron Rd

Eastport, ME 04631

Ph: (207) 853-6081 Fax: (207) 853-6056 Cell: (207) 214-6009

Email: jennifer.robinson@cookeaqua.com
Navigation Notes

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APPENDIX D: USDA APHIS ISAV Control Program Flow Charts

Non-negative Notification Flow Chart

In the case of confirmed infection notify these entities

Action Notification Reporting Flow Chart

Producer 

Contact(s)

USDA-Approved 

Diagnostic Facility

Accredited 

Veterinarian NVSL (notification 

chain same as for lab)

ISA Control Program 

Veterinarian or designee

Maine 

DMR

USDA 

APHIS VS 

District 

Director or 

delegate

Maine State 

Veterinarian

Maine 

AAHTC

ISAV Technical 

Board

Maine 

DIF&W

USDA APHIS VS 

District Director 

or delegate

DMR and ISA Control 

Program Veterinarian 

or designee

Producer 

Contacts

Accredited 

Veterinarian

AQ Program 

Leader 

MAA

Industry

OIE

ISAV Technical 

Board

AQ Program 

Leader OIE
Navigation Notes

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APPENDIX E: USDA Sample Submission Form

USDA APHIS ISA Control Program

ISAV Sample Submission Chain-of-Custody Form

On the top copy, list the pen or cage designation number(s), the year class of fish sampled, and the number of fish 

sampled per cage, whether signs of ISA are present, and the date samples were obtained and submitted. On the 

middle and bottom copies, please also list the marine site by name and Maine DMR code identifier. The collecting 

inspector should sign and date the form, and indicate how samples were sent to the laboratory. All information 

will be treated with confidentiality to the fullest extent of federal law.

USDA ISA Control Program Accession #: 

Laboratory Accession #: _______________________________________________________________

Tag #

(opt.)

Fish 

#

Cage 

#

Viro 

Pool

YC

 Date 

sampled

Water 

Temp 

°C

Sea lice 

counts

Date 

submitted

Lab Use Only

PCR IFAT Culture

1

2

3

4

5

6

7

8

9

10

Clinical Disease Present? __________________________________________________________________

Gross Pathology (List signs by fish #) _________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________ 

_________________________________________________________________________________________ 

_________________________________________________________________________________________

_________________________________________________________________________________________

Site/Cage Mortality (Low, steady, increased) ____________________________________________________

Samples collected by: ______________________________________________________________________

Samples processed by: _____________________________________________________________________

Samples submitted via:

[ ] Diagnostic Laboratory courier [ ] US Mail (Priority Overnight Express)

[ ] ISA Control Program Manager [ ] FedEx

Send report to (print name): _______________________________________________________, DVM

Supervising USDA APHIS VS Accredited Veterinarian ______________________________________

ISA Control Program Manager Countersignature ___________________________________

Date_______________________

Maine DMR Site Identifier Code_________________________________________

White Copy: Laboratory Yellow Copy: USDA Pink Copy: Submitting Veterinarian
Navigation Notes

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Document Navigation Notes:

 In the electronic version of these Standards, you can use the Table of Contents and List of 

Tables to navigate to specific sections (Hold Ctrl and left click to use the hyperlinks). To 

return to the Table of Contents, go to the bottom of any page, double left click to open the 

Footer, hold Ctrl and click the ‘Go to Table of Contents’ hyperlink. To navigate to specific

bookmarks click on Bookmark, choose the appropriate bookmark and then ‘Go To’.

 Hyperlinks: Hold Ctrl and left click hyperlinks throughout the document to get to specific 

hyperlinked sections. In most cases, Shift + F5 will bring you back to the last three cursor 

locations.