How many bloods will a 'HIVCHEK' check? Multiple tests for HIV antibody for a single screening kit

Detection of HIV infection in blood donors or populations is usually by testing sera for antibodies to HIV-1 and HIV-2. Screening tests are now highly sensitive and specific, but still expensive and scarce in Africa. We tested the commercially available kits 'HIVCHEK 1 + 2' in two field laboratories, on specimens from blood donors and antenatal women in rural Zaire. We describe a method of using one test kit for up to five serum samples, saving money and time. In 491 antenatal mothers in Eastern Zaire, among whom the HIV seroprevalence was 3.3%, we compared 'HIVCHEK' results with results obtained by ELISA and Western blot. The 'HIVCHEK' multiple-sample method had a sensitivity of 82% and a specificity of 99.6%. In an area with an HIV seroprevalence of < 4%, using 'HIVCHEK' by the multiple sample method would lead to a saving of about 2,400 pounds for every 1000 individuals tested.