United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture

Factsheet

Veterinary Services July 2003

APHIS

Basically, monitoring and surveillance enables

APHIS to accomplish the following:

• detect outbreaks of an infectious or foreign animal

disease

• estimate the size of disease problems

• characterize changes in disease trends

• evaluate preventive programs

• assist with animal health program planning

• improve knowledge of animal health among health

professionals, industry representatives, and

producers

• identify animal health research needs,

• promote safe international trade of live animals,

germplasm, and animal products, and

• provide scientifically sound evidence of regional

prevalence for trade–significant diseases.

Current Animal Health Surveillance

Programs

VS conducts surveillance programs for brucellosis, pseudorabies, classical swine fever, trichinosis,

tuberculosis, bovine spongiform encephalopathy,

Johne’s disease, bluetongue, scrapie, chronic wasting disease, equine infectious anemia, equine viral

arteritis, contagious equine metritis, equine

encephalitis, low pathogenic avian influenza, salmonellosis, infectious salmonid anemia, and foreign 

animal diseases. 

VS collaborates with other APHIS programs such

as Plant Protection and Quarantine and Wildlife

Services, as well as other State and Federal 

agencies, to conduct surveillance and enhance 

surveillance activities. Furthermore, VS’ Centers for

Epidemiology and Animal Health help VS to track

emerging issues in the global arena, monitor current

disease outbreaks both in the United States and

abroad, and analyze the data that are collected to

identify important animal disease trends.

Foreign Animal Disease Surveillance and

Response

In addition to surveillance for eradication–program diseases, VS conducts foreign animal disease

(FAD) surveillance to rapidly detect the introduction

of exotic or foreign animal diseases that can affect

U.S. livestock, poultry, and aquaculture and prevent

the rapid spread of disease.

Throughout the United States, APHIS has 

foreign animal disease diagnosticians (FADD) who

are available within a 4–hour drive of any continental

The Significance of

Surveillance to

Safeguarding

American Animal

Health

As part of the U.S. Department of Agriculture’s

(USDA) efforts to safeguard U.S. animal health, the

Animal and Plant Health Inspection Service (APHIS)

is constantly on guard and looking for signs of 

foreign and emerging animal diseases. In fact,

APHIS considers surveillance to be the foundation

for its Veterinary Services’ (VS) program activities

including: domestic disease control and eradication

programs, emergency preparedness and response,

and trade. 

VS recognizes and demonstrates through its

activities that a comprehensive, coordinated, integrated surveillance system is the cornerstone of 

animal health, public health, food safety, and 

environmental health. The vast array of detection

and surveillance tools and programs developed and

implemented by VS and its partners are moving

steadily towards an integrated and flexible surveillance system.

But what does surveillance really mean? And

what makes both monitoring and surveillance so

important to safeguarding American agriculture?

Monitoring is the routine collection of information

for a disease condition, characteristic, or state in an

animal population. The purpose of collecting this

information is to detect changes in the epidemiologic

parameters affecting the population. Surveillance

then involves the analysis of those collected data so

that APHIS officials can plan and take the proper

actions to ensure the safety of America’s animal

health.

The Role of Surveillance

By conducting routine monitoring and surveillance, APHIS is able to safeguard and improve the

health, quality, and marketability of U.S. livestock

and poultry—as well as their products—and veterinary biologics in the national and international 

marketplace. 
U.S. location. The FADDs are specially trained to

recognize, test, and diagnose FADs. Once an

investigation is initiated, a FADD is in contact with

someone on the affected premises immediately.

Tissue samples are sent to the U.S. Department of

Homeland Security’s (DHS) Plum Island Animal

Disease Center located off Long Island, NY, or to the

National Veterinary Services Laboratories in Ames,

IA, to rule out the presence of a FAD. USDA then

announces the results of the tests as soon as they

are available.

The total number of FAD investigations in the

United States has increased steadily over the past

few years. This reflects an increased awareness and

alertness on the part of producers and livestock 

owners. Should a FAD be introduced into U.S. livestock or poultry, it could be controlled more readily if

detected rapidly.

In FY 2002, VS' FADDs conducted 837 investigations, an increase from 801 in FY 2001. The most

common type of investigation was for encephalitic

conditions, such as Venezuelan equine encephalitis,

followed closely by vesicular conditions like

foot–and–mouth disease, and then excessive deaths. 

VS’ monitoring and surveillance programs also

enable APHIS to identify new and emerging diseases

or disease conditions both internationally and in the

United States. VS’ Center for Epidemiology and

Animal Health partners with the Office International

des Epizooties (OIE), the international animal health

standard setting organization, and its member countries, to improve international disease surveillance

capabilities and analytic methods supporting trade

decisions. Thus, surveillance enables VS to 

safeguard the health status of imported animals and 

animal products to prevent the introduction of FADs.

In the event of an agri–terror attack on our 

homeland, and APHIS would work as partners to

safeguard America’s food and agricultural resources.

DHS would lead the team of first responders to 

contain and manage the threat while APHIS would

provide crucial scientific and diagnostic expertise.

This expertise would be critical in managing a potential disease outbreak as well as in assisting DHS in

its investigative and intelligence–gathering efforts to

find those responsible for the terrorist attack. Today’s

world presents new threats to U.S. agriculture. This

partnership creates a stronger line of defense to 

protect our Nation’s agricultural resources.

How APHIS Conducts Surveillance

The primary method through which APHIS conducts surveillance to ensure the safety of America’s

food supply is testing for animal pathogens. APHIS

conducts testing of animals and animal products from

countries at risk for diseases to ensure that these

products do not introduce disease into American agriculture. In addition, APHIS, in partnership with State

animal health agencies, conducts surveillance of

U.S. animals and animal products to ensure that a

disease has not been introduced and cannot spread

to other U.S. animal populations. Surveillance

includes: 

• pre–entry and post–entry animal testing and monitoring of animals imported into the United States

• field testing of animals prior to movement from the

farm either for export or sale

• sample collection at slaughter facilities to detect

disease or to confirm the absence of diseases in

carcasses

• routine testing in States classified as free of

diseases for which APHIS has eradication

programs. States must maintain a level of surveillance that is documented and reviewed prior to

renewal of free status.

Continued Enhancement of Animal

Health Surveillance

Animal health surveillance systems are being

faced with significant new demands constantly. It is

important, therefore, for surveillance systems to be

flexible and dynamic. APHIS must be able to detect

foreign and emerging animal diseases, monitor 

disease trends and threats in the United States and

abroad, detect and estimate risk, evaluate control

programs, and provide adequate animal health 

information to various audiences.

To meet these goals, APHIS is moving toward a

national surveillance system. This comprehensive,

integrated, and coordinated system will detect 

animal–health–related events and trends for use by

all stakeholders involved in public, animal, and 

environmental health.

As a part of this move toward an integrated

national surveillance system, APHIS recently has

appointed a national surveillance system coordinator.

The role of the coordinator is to enhance and integrate national animal health surveillance and to

implement the enhancements recommended in the

National Association of State Departments of

Agriculture Animal Health Safeguarding Review. In

addition, the coordinator facilitates effective interaction between APHIS staffs and programs, other

Federal agencies, and stakeholders with a role in

surveillance.

The Importance of a Strong Laboratory

Network to the National Surveillance

System

Diagnostic capability is an essential element of

the national surveillance system. VS’ National

Veterinary Services Laboratories (NVSL) are the only

Federal laboratories dedicated to the testing of diagnostic specimens for domestic and foreign animal
diseases. NVSL also is recognized as an international reference facility by the OIE. NVSL provides

assistance to State and other Federal agencies and

laboratories, educational institutions, and foreign governments in the diagnosis of animal diseases through

training and reagents and conducts developmental

projects for rapidly advancing technologies.

NVSL has taken the lead in the development of a

National Animal Health Laboratory Network (NAHLN)

that addresses diagnostic needs for routine animal

disease surveillance as well as diagnostic capacity

for investigations and control and eradication 

programs.

Under the NAHLN concept, State laboratories

could provide a significant surge capacity during a

disease outbreak. State laboratories could assist in

defining herds for depopulation, delimiting the extent

of the outbreak, and conducting follow–up surveillance to determine “free status.”

The network, currently in a pilot phase, is modeled after the comprehensive response network in

place for public health threats. Among the elements

of the planned NAHLN system are: the development

of standardized, rapid diagnostic techniques that can

be used at the State, regional, and national level;

modern equipment and experienced personnel

trained in the detection of emergent, foreign, and

bioterrorist agents; national training, proficiency testing, and quality assurance; and upgraded facilities

meeting biocontainment requirements.

Additional Information

For more information contact

USDA-APHIS

Veterinary Services Emergency Programs

4700 River Road

Riverdale, MD 20737

Phone: (301) 734-8073

Fax: (301) 734-7817

or visit the APHIS Web site at www.aphis.usda.gov

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