September 28 is World Rabies Day. It was started in 2007 to raise awareness of rabies and its continued impact around the world. The incidence of rabies in domestic animals has been greatly reduced in the US due to vaccination efforts, however, it is still a concern and it is still important to vaccinate your pets.
Tips for submitting samples 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 crosssection 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 anatomic pathologist.
-Heidi Pecoraro, DVM, PhD, DACVP
Images courtesy of the Public Health Image Library, #1958, #6455.