Media playback is unsupported on your device Media caption OraSure says it is planning a major advertising campaign around the new home HIV test

A home HIV test is expected to go on sale in the US within months, after winning regulator approval.

The OraQuick test checks saliva from a mouth swab for HIV and can produce results in 20 to 40 minutes.

Government estimates suggest 1.2 million people in the US are HIV-positive, but 20% do not know they are.

The Food and Drug Administration (FDA) has said it hopes the over-the-counter test will reach people who might not otherwise get tested.

The test is expected to be sold in as many as 30,000 pharmacies and homeware shops, as well as online.

The manufacturer, OraSure, has not said how much the test will sell for but confirmed it would cost less than $60 (£38).

"We expect all the major retail outlets to carry this product," chief executive Douglas Michels said.

The company is planning a "pretty massive effort" to market the test, Mr Michels added.

'Empowering people'

Approval of the test has been praised by HIV/Aids awareness groups.

"This test will allow anyone to empower themselves to know their HIV status when, how and with whom they want to," Tom Donohue, founding director of Who's Positive, told the Associated Press.

But the FDA has highlighted in its announcement that the test may not be 100% accurate, and has stressed the need for additional testing by medical professionals to confirm the result.

OraSure said that in trials the test was able to correctly detect HIV among people carrying the virus only 92% of the time.

It was 99% accurate for negative results - or identifying that someone does not carrying the virus.

Meanwhile, Dr Jonathan Mermin, director of the HIV unit at the Centers for Disease Control and Prevention, said people who receive negative results should take the test again after three months, because it can take weeks before antibodies to HIV appear.

Healthcare professionals have been using a version of the OraQuick test since 2002.

For the last two decades there have been about 50,000 new cases of HIV in the US each year.