Prevalence of drug resistant HIV in the UK on the rise

This article is more than 21 years old.

The number of people with UK who have drug resistant virus is growing, according to figures published by the Health Protection Agency last Friday.

The figures highlight an increase in the number of antiretroviral treatment naïve individuals infected with a strain of HIV that is already resistant to at least one drug, from 10% in 1996 to 14% in 2001 to a preliminary figure of 21% in 2002.

There has also been a substantial increase in the number of treatment-experienced patients who are resistant to the three main classes of anti-HIV drugs. In 1996 1% of HIV-positive individuals were resistant to NRTIs, protease inhibitors and NNRTIs. This had increased to 14% by 2001, remaining steady at 13% for 2002. However, data for 2002 are incomplete and the Health Protection Agency are cautioning that the figure is likely to increase as further reports come in.

Glossary

strain

A variant characterised by a specific genotype.

 

drug resistance

A drug-resistant HIV strain is one which is less susceptible to the effects of one or more anti-HIV drugs because of an accumulation of HIV mutations in its genotype. Resistance can be the result of a poor adherence to treatment or of transmission of an already resistant virus.

treatment-naive

A person who has never taken treatment for a condition.

treatment-experienced

A person who has previously taken treatment for a condition. Treatment-experienced people may have taken several different regimens before and may have a strain of HIV that is resistant to multiple drug classes.

naive

In HIV, an individual who is ‘treatment naive’ has never taken anti-HIV treatment before.

Amongst patients failing therapy, resistance to one drug has remained steady at between 70% - 80% since 1996.

Dr Barry Evans of the Health Protection Agency warned that these figures might not tell the full story saying, “it is important to bear in mind when looking at these figures, that we are not able to test for drug resistance in all patients with HIV.?Indeed, the Health Protection Agency points out that resistance tests were performed on only 4% of the 19,000 people taking anti-HIV therapy in the UK last year. Of these, 21% had no resistance, 24% were resistant to one drug class, 43% to two drugs classes, and 13% to all the three main drug classes.

Increasing levels of drug resistance made it essential to continue the development of new classes of anti-HIV drugs, said Dr Evans. He added, “safer sex messages targeted at people living with HIV are essential in order to prevent onward transmission of drug-resistant strains of the virus to newly-infected individuals.?

Further information on this website

Resistance - factsheet

Booklet on resistance - in the award winning information for HIV-positive people series

References

Health Protection Agency. Communicable Diseases Weekly 13(46) October 23rd, 2003.