What tests are available to diagnose HIV?

Testing for HIV

Traditional testing for HIV consists of an initial enzyme immunoassay followed by confirmatory Western blot or immunofluorescent assay. The enzyme immunoassay has very high sensitivity so false positives are rare.

Oral rapid hiv tests provide results within 1 hour. However, a recently published study found higher false positive rates with an oral rapid test. A positive result from oral rapid testing must be confirmed with traditional testing.

Screening for HIV

The goal of screening for HIV is to identify patients with undiagnosed HIV so that timely treatment is provided and transmission is prevented.

High risk patients should be regularly screened for HIV. Groups at increased risk include men who have sex with men; men and women who have unprotected sex with multiple partners; injection drug users; men and women who exchange sex for money or drugs or have sexual partners who do; individuals whose past or current sexual partners were infected with HIV, were bisexual, or were injection drug users; persons being treated for STDs; and persons with a history of blood transfusion between 1978 and 1985. Patients who receive health care in high prevalence or high-risk health care settings are also a high priority for screening. High-risk settings include STD clinics, correctional facilities, homeless shelters, tuberculosis clinics, clinics serving men who have sex with men, substance abuse clinics, and adolescent health clinics with a high prevalence of STDs. High-risk patients who are tested because of a viral syndrome that may represent acute HIV infection may require additional testing in addition to HIV antibody tests, because anti-HIV antibody tests may not be reactive during acute infection.