The use of saliva for the detection of IgG and anti-bodies against rubella virus: comparison of indirect ELISA and antibody capture immunoassay.

Serum and saliva specimens, collected simultaneously from 26 normal adult females, were tested for IgG and IgA antibodies to rubella virus by indirect ELISA and antibody capture assays. Antibody capture assays were found to be more sensitive than indirect ELISA for the detection of IgG and IgA antibodies in saliva samples whereas both assays were similar in sensitivity for the detection of IgG and IgA antibodies in serum samples. Comparison of the results obtained from serum and saliva samples showed that by an indirect ELISA test 13 out of the 22 seropositive subjects were also positive for antibodies in their saliva. So this test had 9 false negative results, whereas by an antibody capture assay 18 out of 22 seropositive subjects were also positive for antibody in saliva. Thus there were only 4 false negative results. Further comparison of results derived from testing serum and saliva are needed before recommending the use of saliva alone for detection of antibodies to rubella virus.