Anti-HIV antibody in saliva: an assessment of the role of the components of saliva, testing methodologies and collection systems.

The various components of saliva, namely mixed saliva, parotid saliva, submandibular saliva, crevicular fluid and minor (labial) gland secretions, were collected from 63 known HIV antibody seropositive patients. A commercial test system, Wellcozyme HIV 1+2, and an antibody capture ELISA (GACELISA), were compared for sensitivity against all components. Sensitivity of the GACELISA system was 100% in 123 mixed saliva, 121 parotid saliva and 127 labial fluid samples, and 98% in 99 submandibular samples and 127 crevicular fluid samples. Respective figures for Wellcozyme 1+2 were 92%, 55%, 73%, 66% and 63%. Mixed saliva was most easily, conveniently and effectively collected using a plain Salivette. In 241 Salivette samples examined from the 63 patients, GACELISA proved 100% sensitive, and Wellcozyme 95% sensitive. Another form of Salivette impregnated with citric acid was unsuitable for GACELISA and gave a false negative value of 45%. In 197 samples from the gingival margin taken by a dry swab, GACELISA showed a sensitivity of 98% and Wellcozyme 81%. The most sensitive method for demonstrating anti-HIV antibody in saliva is to collect mixed saliva with the plain Salivette system and assay anti-HIV antibody levels by GACELISA.