For diagnostic tests, affected tissues/liquid are preferred, if available. Swabs can be useful ante-mortem diagnostic tools. To insure a valid result, appropriate swabs and collection systems must be used since the inappropriate swab type/system can nullify a test result or prevent a test being used. Cotton-tipped, wooden-handled swabs are no longer considered acceptable for Molecular Diagnostics or Virology tests. Chemicals used in the processing of both the cotton and the wood are known to inhibit viral growth, and can inhibit some PCR-based tests. Recently, foreign animal disease (FAD) investigations have been delayed or negated because the index samples were collected and submitted in the wrong/incorrect collection system. To insure valid, meaningful test results, Purdue ADDL has developed these recommendations for use of swabs for diagnostic testing.

DIAGNOSTIC SECTIONS	TEST(S)	ACCEPTABLE COLLECTION SYSTEMS	EXAMPLES OF ACCEPTABLE COLLECTION SYSTEMS
Bacteriology	Aerobic Culture	Preferred: Commercial bacteriological culture system	Any commercial bacterial collection/transport system (BD CultureSwab™, Remel BactiSwab®, etc). Most include Amies or Modified Stuart’s transport media.
		Acceptable: Cotton-tipped, wooden-handled swabs	Swabs must be placed in a leak-proof sterile container, such as a red top tube, with 0.5mL sterile saline to prevent desiccation.
	Anaerobic Culture	Commercial ANAEROBIC bacteriological culture system	BD Port-a-Cul™ Starswab® Anaerobic Transport System, Starplex®
	Mycoplasma Culture	Dacron (polyester) swab AND Viral/universal transport media (ONLY)	BD Universal Viral Transport Kit Puritan UniTranz-RT® Transport System
Molecular Diagnostics (PCR)	For bacteria	Dacron (polyester) swab
	For viruses and mycoplasmas	Dacron (polyester) swab AND Universal transport media (ONLY)	BD Universal Viral Transport Kit Puritan UniTranz-RT® Transport System
Virology	Virus isolation	Dacron (polyester) swab AND Universal transport media (ONLY)	BD Universal Viral Transport Kit Puritan UniTranz-RT® Transport System Sterile saline is acceptable if viral transport vials are not available.

IMPORTANT NOTES:

1. Tissues/liquid are preferred over swabs, if available, and should be submitted in a sterile container with no additives. Sample size >2mL or >2cm3 is adequate to preserve anaerobes.
2. If swabs are used, they should be collected within the first few days of onset of symptoms.
3. Dry swabs will not be processed.