The United Kingdom's Health Protection Agency's National HIV Resistance Database shows that the percentage of HIV-positive treatment-naive adults in the country who are infected with virus resistant to at least one antiretroviral medication has increased 40% since 1996, AIDS Weekly reports. The percentage of treatment-naive patients with drug-resistant virus rose from 10% in 1996 to 14% in 2001, according to agency officials. The figures indicate that people taking antiretroviral drugs and developing resistance to them are passing along their drug-resistant strains of the virus to their sex partners or through the sharing of injection-drug paraphernalia. The database also showed that the percentage of people taking antiretroviral drugs who were resistant to medications from three drug classes rose from 1% in 1996 to 14% in 2001.
But health care experts in the country warn that the figures don't indicate that antiretroviral therapy is failing most HIV-positive people in the country. "Drug-resistance testing only tells us about the virus in patients in whom therapy is not working or in whom therapy has not yet started and is not a reflection of all patients receiving treatment," said Barry Evans of the Health Protection Agency.