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Division of Consolidated Laboratory Services


Laboratory: Immunology/Virology and Molecular Detection and Characterization

Test Description: Direct and Indirect fluorescent antibody tests are useful in examining original specimens as well as identifying tissue culture isolates. These methods may be used to detect the presence of a viral agent from a large variety of viral agents or identify a specific viral serotype from other closely related serotypes.

Monoclonal antibodies are employed in DFA (Direct Fluorescent Antibody) and IFA (Indirect fluorescent Antibody) as well as conventional polyclonal antibodies. These are usually components of commercially produced identification kits which have undergone extensive testing by manufacturers and are usually FDA approved. Always refer to and be familiar with the protocol of the specific manufacturer's kit insert before beginning any procedure.

Order Approval Required? Yes

Specimen Type: Viral Isolate

Collection Container: Viral Transport media (VTM)

Optimal Volume: 3ml

Collection Guidelines: Specimens should be obtained early in the course of illness, when the viral titer is highest, but viral shedding depends on the type of virus and the degree of systemic involvement. Store viral isolates at room temperature and ship with warm packs.

Storage Container: Inoculated monolayer

Storage Instructions: Samples should be stored at 2 to 8 °C until shipped to the laboratory.

Transportation Instructions: Samples should be refrigerated prior to and during shipping

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

Additional Information: If specimen is collected on Friday, holiday or weekend, contact lab at 804-648-4480 ext. 271 prior to submission

Causes For Rejection:

  • Quantity not sufficient for testing
  • Improperly labeled specimen
  • Out of holding time

Possible Results: 1. No virus isolated 2. Specific virus isolated