Diagnostic Kits 3 of 8 

Outline of Production

See the Outline of Production chapter of this manual and VS Memorandum 800.73 for general 

guidance on reviewing the Outline of Production for kits. The Outline template for diagnostic 

test kits is found in 9 CFR 114.9(f). There are seven sections within the Outline of Production 

for a diagnostic kit: 

Introduction: This section contains the principle of the test, recommended test samples, 

reagents included in the kit, products obtained via split manufacture, and the test 

interpretations and limitations. The split manufacture section (subsection 5) should include 

only licensed FFM biologics. Most of the information in this section and Section VI.D will 

be included in the product Circular Label. 

Sections I and II. Antibody Components and Antigen Preparation: 

These sections should include information on the preparation of antibody, antigen, and 

peptide components used for capture, detection, and for the positive and negative controls. 

For PCR test kits, information regarding the PCR primers should be included in Section II, as 

should information regarding nucleic acid positive and negative controls. Firms are 

permitted to use purchased antibody, antigen, or peptide reagents or PCR primers in the 

manufacture of their kit if properly identified with the source and catalogue number. 

Purchased reagents are not required to be obtained under an FFM license. The firm’s criteria 

for accepting the reagent into their facility should be listed. The production processes used 

by the reagent supplier should not be included in the Outline of Production. 

If firm produces specific antibody (polyclonal or monoclonal) or antigens, they must follow 

the Master Seed and Master Cell concept and describe the production process. If synthetic 

peptides or nucleic acids are used, the firm must follow the Master Sequence concept. The 

target specificity of antibodies (e.g., recognized epitope, protein, or glycoprotein) should be 

stated. If a monoclonal antibody is prepared, the Outline of Production should not contain 

the production steps that were used to produce the hybridoma. 

Section III. Preparation of Standard Reagents:

This section lists the preparation of the positive and negative controls, conjugate, substrate, 

inert buffers, diluents, and other reagents directly packaged as kit components. Buffers and 

diluents used in the manufacture of kit components (e.g., coating buffer used to prepare 

coated plates) should be listed in the appropriate Section (I, II, or IV) where they are utilized.

Section IV. Preparation of the Product:

The template for Section IV, as listed in 9 CFR 114.9, is a bit confusing. Section IV.A lists 

the kit preservatives. Section IV.B describes the filling, plating, or attachment of antibody or 

antigen to the solid phase . Section IV.C describes the filling method and minimum and 

maximum fill volumes of the kit components. Section IV.D describe the handling of 

unsatisfactory materials. 

Section V. Testing:

See VS Memorandum 800.73, Section VII.F, for guidance on serial release testing for kits. 

Diagnostic Kits 5 of 8 

calculation of cutoff values. Wash buffers and diluents are not critical components. Within a 

serial, there may be several production lots of noncritical components. 

Label Claims

As with any biologic, all label claims must be specific and supported by data filed with the CVB. 

Kits typically have claims to detect antigens or monitor serological status. For diagnostic test 

kits, labeling should specify: 

1. Species of animal: this must be specific (e.g., cattle), not general categories (e.g., ruminants)

2. Specific sample type: e.g., whole blood, serum, or plasma; retropharyngeal lymph node or 

popliteal lymph node. 

3. If the kit claims to differentiate vaccinated and infected animals, the specific vaccines may be 

stated if apropriate. 

4. If the kit is specifically approved as a screening test or as a confirmatory test, a clear 

indication statement should be included. 

5. Other specifications may be warranted, depending on the data submitted and the intended 

use. For example, it may be prudent to specify the time period after vaccination during 

which the kit is adequately sensitive. 

6. The use of symbols on labels are permitted under CVB policy with certain considerations. A 

list of symbols approved for use on APHIS regulated veterinary biologics labeling may be 

found at: 

https://www.aphis.usda.gov/animal_health/vet_biologics/publications/ISOsymbolsLabels.pdf

7.

Restrictions

If you are working with a kit for an exotic disease or a disease which is part of a declared or 

undeclared APHIS eradication and control program, it is likely the license will be restricted to 

avoid potential misuse. Such products may be restricted to use under the supervision of APHIS 

or State officials. 
Diagnostic Kits 6 of 8 

Appendix 1 

Gold Standard Assays to Determine the Diagnostic Sensitivity and Specificity of 

Antigen Test Kits

Agent Gold Standard

Avian Influenza Virus Virus Isolation

Avian Leukosis Virus COFAL

Bovine Virus Diarrhea Virus Isolation/ rtPCR

Canine Parvovirus HA/HI

Classical Swine Fever Virus Isolation

Feline Immunodeficiency 

Virus Virus Isolation 

Foot-and-Mouth Disease 

Virus Virus Isolation 

Giardia lamblia fecal wet mount

Infectious Bovine 

Rhinotracheitis Virus Virus Isolation 

Parvovirus (canine) Virus Isolation / fecal hemagglutination

Heartworm (canine or feline)

necropsy worm count, with breakdown into the number of 

male and female worms (acceptable to compare to a 

licensed kit for negative samples, to avoid sacrificing 

healthy animals)

Mycobacterium avium spp. 

paratuberculosis fecal culture

Transmissible Spongiform 

Encephalopathies immunohistochemistry on obex