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Division of Consolidated Laboratory Services


Laboratory: Immunology/Virology

Test Description: Anti-rabies antibodies, conjugated with fluorescein isothiocyanate (FITC), are incubated with potential virus infected tissue. In the presence of rabies virus, antigen-antibody complexes will form. If the tissue being examined contains no viral antigen, these antigen-antibody complexes will not be formed.

Rabies virus-anti-rabies antibody complexes are examined using a fluorescent microscope. Positive reactions demonstrate bright, apple green fluorescence of particles ranging in size and morphology from 'dust particles' to prominent cytoplasmic inclusions referred to as 'Negri bodies'.

Order Approval Required? No

Specimen Type: Animal Brain

Collection Container: Double bagged with absorbent material (newspaper) around head

Optimal Volume: Hippocampus, Cerebellum, and brain stem

Collection Guidelines: Only animal heads and brains should be submitted for testing. The entire carcass of small animals such as rodents (I.e. the approximate size of an adult squirrel) or bats may be submitted.

Storage Container: Store in refrigerators or coolers with ice packs prior to shipping,

Storage Instructions: Should be stored in -70°C freezer

Transportation Instructions: Transport in biohazard bags and coolers

Test Methodology: Direct Fluorescent Antibody (DFA) and Indirect fluorescent Antibody (IFA)

Additional Information: Must have Virginia Department of Health (VDH) approval to perform test and must be exposure related.

Causes For Rejection:

  • Animal submitted for testing without documented human or domestic animal exposure
  • Specimens submitted in formalin or in any other fixative
  • Decomposed samples
  • Samples with unidentifiable brain parts
  • Samples lacking brain parts

Possible Results: Positive, Negative