Two hundred HIV positive delegates meeting in Coventry were told that 10% of the estimated 16,000 people on combination therapy drugs are not responding to treatment.

They fear the number could rise if doctors do not give people more advice and support about taking the drugs.

Some patients have to take up to 30 pills a day. Many have to be taken at particular times of the day to be effective and meal times often have to be tailored to the drug timetable.

Some of the drugs also have strong side effects, for example, nausea.

If people do not take them correctly, HIV can become resistant to them, meaning they have to switch to other drugs.

Combination therapy - a cocktail of different anti-HIV drugs which can lower the virus to undetectable levels - was introduced in the UK in 1996 and is said to have reduced the Aids death rate by 75%.

Staying alive

Paul McCrory, chair of the Network of Self-Help HIV and Aids Groups (NSHHA), said: "Many people are not getting advice from their doctors about how to keep up with this level of medication.

"It is vital that doctors, and the companies that produce these drugs, address this issue seriously so we can keep people with HIV alive and well."

Combination therapy has reduced the Aids death rate by 75%

Many HIV organisations have published leaflets and information on the subject of drug regimes to help patients, and the Terrence Higgins Trust has special HIV positive volunteers whose job is to help people take the drugs.

The number of people newly infected with HIV is rising, with 3,000 new cases last year - the highest number since the epidemic began.

Many others are living with HIV on combination therapy, but only 39% in a recent survey said their doctors had given them advice about how to take the drugs.

Less than a third said the advice was written down so they could look over it at home.

The patients as expert

The conference, organised by the National Aids Trust, the UK Coalition of People Living with HIV and Aids (UKCPLHA) and the NSHHA, also heard calls for more recognition for the role HIV positive people have played in educating people about Aids.

Ian Kramer, deputy chair of the UKCPLHA, said: "We are the experts when it comes to how this virus is transmitted."

He said HIV positive people should be at the centre of policies and education initiatives to stop the virus from spreading.

Public health minister Tessa Jowell told the conference the government was putting together new policies on HIV and would be involving HIV positive people.