Advertisement
The Body: The Complete HIV/AIDS Resource
Follow Us Follow Us on Facebook Follow Us on Twitter Download Our App
Professionals >> Visit The Body PROThe Body en Espanol
   
Ask the Experts About

Safe Sex and HIV PreventionSafe Sex and HIV Prevention
           
Rollover images to visit our other forums!
Recent AnswersAsk a Question
  
  • Email Email
  • Glossary Glossary


Gardasil plus flu vaccine, false positive HIV?(INFLUENZA VACCINATION AND INDETERMINATE WESTERN BLOT TESTS) (FLU SHOT AND FALSE POSITIVE HIV TESTS)
Dec 15, 2007

A week ago my 17-year-old daughter received a letter from Red Cross indicating she screened HIV positive after donating at a recent blood drive. Results were HIV-1/HIV-2 Positive, Confirmatory Indeterminate, NAT Negative. Retesting was done at a hospital lab. Results are HIV (weak) negative and we await Confirmatory results. My daughter appears to have no risk factors. She is a virgin, has no history of sexual activity whatsoever, no tattoos, no IV drug use. Ten days before the blood donation she received (her first ever) flu vaccine and also the second of three Gardasil shots. She was also prescribed Provera a month earlier. After reading previous posts I believe you draw no correlation between vaccines and false positive HIV tests, however there does seem to be recent information to the contrary. Information published in March 2006 in the New England Journal of Medicine asserts recent inoculation with any brand of influenza vaccine was significantly associated with a false positive screening assay for HIV antibodies. Guidelines of both Johns Hopkins and the New York State Department of Health list influenza vaccination as a known cause of indeterminate results on Western blotting for HIV antibodies. Given the escalating international awareness of various influenza strains, it is very important to remind patients and clinicians that influenza vaccination may cause cross-reactivity with HIV antibody assays. I'm not qualified to debate the validity of this information, but it is somewhat comforting for a family in a situation like ours to think that a vaccine might be the issue. My question: What is your opinion of the likelihood of an HIV positive confirmation considering my daughters history? Thank you.

Response from Dr. Frascino

Hello,

Thanks for your post. Yes, we are trying to get this more recent information out to a wider audience. The influenza vaccine changes from year to year to cover the most likely flu strain candidates for the coming flu season. We do have recent information that flu vaccination can cause some degree of nonspecific cross-reacting antibodies, which can confound HIV-antibody tests. Generally speaking, these cross-reacting antibodies cause "indeterminate" rather than "false positive" HIV tests. Please note a reactive ELISA with subsequent indeterminate Western Blot is considered to be an "indeterminate" HIV test result, not a positive test! HIV testing center and certainly HIV specialists are well aware of these potential complicating factors and we have methods for sorting out serological results that are either in dispute or indeterminate.

In your daughter's case of essentially no potential HIV exposure and a recent flu vaccine, you can rest assured her indeterminate Western Blot is not related to HIV seroconversion, but rather to the detection of cross-reacting antibodies. That her NAT was negative confirms this fact, because NAT testing does not rely on antibody detection.

Happiest Holidays to you and your entire family.

Dr. Bob



Previous
re: dr. bob's occupational exposure
Next
UNEASY IN THE BIG EASY

  
  • Email Email
  • Glossary Glossary

 Get Email Notifications When This Forum Updates or Subscribe With RSS


 
Advertisement



Q&A TERMS OF USE

This forum is designed for educational purposes only, and experts are not rendering medical, mental health, legal or other professional advice or services. If you have or suspect you may have a medical, mental health, legal or other problem that requires advice, consult your own caregiver, attorney or other qualified professional.

Experts appearing on this page are independent and are solely responsible for editing and fact-checking their material. Neither TheBody.com nor any advertiser is the publisher or speaker of posted visitors' questions or the experts' material.

Review our complete terms of use and copyright notice.

Powered by ExpertViewpoint

Advertisement