A UK company has launched a new HIV testing service, but AIDS charities have warned customers that they are not as reliable as going to a clinic.

For £25, DrThom will analyse a sample of saliva for HIV antibodies. Customers take the sample themselves and sent it through the post to the company’s laboratory.

If antibodies, which indicate the presence of the HIV virus, are present the customer is contacted by phone and advised to get a blood test. If no antibodies are detected the customer is sent an email.

Avert, an international AIDS charity, has said that people who are genuinely worried they may have HIV should get a free test from an NHS clinic. Saliva testing is less reliable than the standard blood test. It also will not show up an infection within the last three months.

“I would still recommend that if people are genuinely worried they may have HIV, they should go to a local NHS genito-urinary clinic to be tested,” Annabel Kanabus, director of Avert, told the BBC.

An estimated 63,500 adults were living with HIV in the UK at the end of 2005, of whom 20,100 (32%) were unaware of their infection.

In 2005, there were at least 7,450 new diagnoses of HIV, contributing to a cumulative total of 82,593 reported by the end of September 2006.

There have been 22,501 diagnoses of AIDS in the UK. At least 17,152 people diagnosed with HIV have died, and at least 80% of these deaths followed an AIDS diagnosis.

DrThom claim their product is aimed at people who are concerned about HIV but do not want to visit a clinic.

A spokesman for the company said: “The test can tell if a person shows no signs of HIV, but is unable to make a firm diagnosis.”

Customers who are found to have positive antibodies will have access to DrThom’s telephone counselling.