MULTICENTER STUDY ON THE PREVALENCE AND DIAGNOSIS OF HIV-2 INFECTION AMONG HIGH-RISK INDIVIDUALS IN SPAIN (1991)

BACKGROUND: To January 1991 thirteen cases of HIV-2 infection had been reported in Spain. Paradoxically, neighboring countries, i.e. France and Portugal, have reported more than one thousand cases, and are the most HIV-2-prevalent areas outside West Africa. We report the results of a prospective, nationwide study on the prevalence of HIV-2 infectio n conducted in Spain in 1991. In addition, an evaluation of testing me thodologies is made. METHODS: Sera collected from 8,073 individuals at high-risk for HIV infection were screened by a combined HIV-1 plus HI V-2 ELISA. Reactive samples were further evaluated by three tests, as HIV-1 Western blot (WB), HIV-2 specific WB, and a synthetic peptide as say immuno-dot (Pepti-lav, Pasteur). RESULTS: Fifteen (0.18 %) individ uals met criteria of HIV-2 infection in both specific WB and SPA. Four (27 %) of them showed reactivity to both HIV-1 and HIV-2, and the dua l infection was confirmed by polymerase chain reaction (PCR) in 2 out of 3 available samples. The SPA showed higher sensitivity and specific ity than WB in the diagnosis and distinction of HIV-1 and HIV-2 infect ions. CONCLUSIONS: To January 1992, 28 cases of HIV-2 infection have b een described in Spain. All but two were African immigrants. The first cases of HIV-1 plus HIV-2 coinfection have been identified. In HIV hi gh-risk populations, SPA may provide an excellent alternative to WB to confirm ELISA reactive samples.