A non-reactive HIV test means that HIV was not found in that testing sample. This test result is commonly referred to as "negative," although a person who tests negative for HIV may nevertheless actually be HIV positive.
HIV tests are used to find antibodies to the virus. Developing a detectable level of antibodies (enough antibodies to be found by a test) is a process called seroconversion.
HIVTest.org reports that seroconversion takes an average of 25 days after infection, but may take as long as three to six months.
An HIV test will only yield a true positive if the tested individual has already seroconverted. A test taken before seroconversion occurs will be inaccurate.
A person who has not contracted HIV will also have a non-reactive test. However, there are a very small number of people who test false positive; this error can be discovered with another HIV test.
People seeking HIV testing should speak with a health-care professional to determine if a test at that time will yield an accurate result, based on the date of the last possible exposure to the virus.