HIV-2 in the United States

Between 1988 and June 2010, the Centers for Disease Control and Prevention (CDC) received reports of 242 cases of HIV-2 infection in the United States, of which 166 met the working definition (consisting primarily of molecular responses to specific immunoassays) that had been previously developed by a workgroup. [HIV-2 Surveillance] The 166 cases constituted 0.01% of the US HIV infections reported during that period.

These HIV-2 cases were concentrated in the Northeast (66%) and occurred primarily among persons born in West Africa. Of the 164 HIV-2 patients whose birthplace was known, 132 (81%) were born in West Africa, 11 in other parts of Africa, 9 in India, 5 in the United States, 3 in Europe, and 2 in Mexico. Of all 166 cases, 77 (46%) were reported from New York City, 33 (20%) from elsewhere in the Northeast, 24 (15%) from the South, 18 (11%) from the Midwest, and 14 (8%) from the West. Other demographics include: 89% were non-Hispanic blacks, 58% were men, and the median age at diagnosis of HIV infection was 39 years. (The countries of origin representing ≥ 10 cases of HIV-2 infection included Ivory Coast, Ghana, Cape Verde, Gambia, Mali, Senegal, and Liberia.) Ninety-seven of the HIV-2 cases also had a positive HIV-1 Western blot antibody test result. Such immunoblot antibody tests currently in use cannot reliably detect HIV-2 infections. [De Cock, Porter 1991] In patients whose HIV-1 test results are atypical or inconsistent with clinical findings that support suspicion of HIV infection, especially for persons from West Africa, practitioners should consider further testing that is specific to HIV-2 infection.

In 120 (72%) of the 166 patients, no transmission risk factor was identified, including 78 cases among individuals with a history of heterosexual contact but with sex partners whose infection status was either unknown or known to be negative. The reported risk factors for the other 88 patients were heterosexual contact with a sex partner known to be HIV-positive (38 patients, 23%), male-to-male sexual contact (4 patients, 2%), and injection drug use (4 patients, 2%). Of the 50 women 15 to 44 years of age at diagnosis, 24 (48%) were pregnant at or after HIV-2 diagnosis. None of the children born to these 24 were reported to be HIV-infected, but follow-up information was missing for 6 of the children born after the mother's diagnosis.

Although both HIV-1 and HIV-2 can be transmitted by the same modes and can both progress to AIDS-defining conditions[De Cock Brun-Vézinet 1991], individuals infected with HIV-2 are less likely to develop AIDS and the clinical management of HIV-2 infection differs from that of HIV-1. [Ntemgwa 2009, DHHS Guidelines 2011]




Howard University College of Medicine AIDS Education and Training Center - National Multicultural Center