ZocdocAnswersCan the flu vaccine cause a false positive HIV test?

Question

Can the flu vaccine cause a false positive HIV test?

I'm worried that I had an HIV exposure about 4 weeks ago, but around that time I also got a flu vaccine. Is it true as I keep reading online that this vaccine can give you a 'false positive' result on an HIV test when you don't really have it?

Answer

This is an example of how a disproven theory can continue to propagate through the internet, even 20 years after the incident. There was a suggestion back in the early 90s that getting the flu vaccine may make the HIV test positive even if the person was not HIV positive. This was found to be related to some defective test kits and not the flu vaccine itself. Today's HIV testing is extremely accurate. This is because of the use of two types of tests. First the ELISA antibody test is used which will detect anyone that has been exposed to HIV, but may be positive in some people that are not actually infected. After someone gets a positive ELISA test, then the Western blot technique is done which is much less likely to be positive in people not infected with HIV. No one gets a diagnosis of HIV without having both tests positive. For this reason, the number of people that get an HIV diagnosis that are not actually infected is extremely small. The best type of physician for you to see for your HIV scare is a primary care physician such as your family doctor. You can discuss some of the symptoms you likely would have by now if you were infected. In a few months, you can have the HIV test.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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