Sample Submission Guidelines for Rabies Testing

Testing for rabies virus infection is performed using the direct fluorescent antibody assay (DFA). The test method is outlined by the Centers for Disease Control and Prevention in the “Protocol for Postmortem Diagnosis of Rabies in Animals by Direct Fluorescent Antibody
Testing”(available at www.cdc.gov/rabies/pdf/rabiesdfaspv2.pdf).

The minimum standard for this test requires a cross-section of the brain stem and a cross section of the cerebellum or hippocampus. Whole brain submission is required for this test to have a conclusive negative result. All positive results, no matter what brain sections are used, are considered positive for rabies virus infection.

The DFA will be performed on partial brain sections submitted; however, if the DFA is negative, the results will be listed as inconclusive. All rabies testing at the VDL comes with additional histopathologic evaluation of brain sections (if available) by a board-certified veterinary anatomic pathologist.

Revised 10-2019

Printable version available here.