The McGill University Health Center study, published in PLoS Medicine, demonstrated the efficacy of rapid saliva tests for all subtypes of HIV-1 and HIV-2 and produced results in as little as 20 minutes.

The saliva test, based on a method called immunochromatography, was used on 1,222 mothers in a labor ward in India using both saliva and blood samples. The results from both types of tests corresponded.

The labor ward saliva tests helped identify several HIV infected women who were about to give birth.

"In such cases, it is vital to determine the HIV status of the mother very quickly to prevent transmission to the child during delivery. Many Indian women do not receive prenatal care and therefore do not get tested for HIV during pregnancy," study leader Dr. Pant Pai says in statement.

"Testing in the labor ward is the last chance to prevent HIV transmission to the newborn baby. Also Indian patients often refuse blood collection, while saliva collection poses no problem."