Paired samples of saliva and serum from 286 high-risk subjects were tested for HIV using two commercial enzyme immunoassays following the same WHO testing strategy supplemented with a Western blot technique. Agreement between HIV testing in both sample types was 98.9% (95% confidence interval: 97.7-100). The sensitivity of an EIA (Wellcozyme GACELISA) alone for saliva was 100% (133/133) and the specificity 98.7% (151/153). These results support previous data showing that in some situations saliva might be an effective alternative to serum for HIV testing.