Each year, 40,000 Americans become infected with HIV, joining more than 1 million who are HIV-positive. About 25 per cent of them do not know they are carrying the disease, which means they get no treatment and may transmit it to their sex partners. The Food and Drug Administration is now considering over-the-counter sales of a home test that is 99 per cent accurate.

Until now, testing for AIDS has been combined with provisions for immediate counselling out of concern that those with positive results might commit suicide. But antiretroviral drugs have made AIDS more a chronic disease than a death sentence, so it makes sense for the FDA to permit the sales of OraSure Technologies’ OraQuick Advance test. The test has been used in doctors’ offices and clinics since 2002. One shortcoming of OraQuick is that it will not detect the virus after a recent exposure, since the test indicates the presence of antibodies that take several weeks to appear.

Until a vaccine for AIDS is developed, the disease will continue to take a horrific toll, especially

in poor countries with limited access to AIDS drugs. In developed countries, the availability of many different AIDS drugs has gone a long way to make the disease treatable and destigmatised. The availability of home HIV tests would be another step forward.