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"Can a flu shot affect HIV test results?"

ZocdocAnswersCan a flu shot affect HIV test results?


Are flu shots known to have any effect on the results of the HIV test? I just got back a negative result on my HIV test but I've heard that false negatives are a real problem with the HIV test, and I got a flu shot not long ago. Should I get another HIV test sometimes soon to make sure?


The basic principle of the HIV test is that it tests for antibodies that form to the infection with the virus. This is true of both the blood and oral swab tests. This test is quite sensitive and actually false negative are not much of a problem with the test (false positives are though). The only time that the antibody test is not completely accurate is in the first few weeks after becoming first infected with the virus because in the first few weeks the antibodies have not yet been formed. If you feel that you might recently have been infected, you should say this to your doctor as a different test can be performed in this window of time. Fortunately, the flu shot does not have any effect on the results of the test! As always the diagnosis and the management of your particular concern will require a physical examination by your personal physician. Setting up an office visit with your primary care doctor if you still have questions might be indicated.

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