A study released Wednesday at the International AIDS Society HIV Conference on Pathogenesis and Treatment in Paris shows that about 10% of all people in Europe newly infected with HIV are resistant to at least one anti-HIV medication, a figure that the lead study author found "surprisingly high," The New York Times reports. Because drug resistance was detected in cities and towns throughout Europe and not just in one local area or in one particular high-risk population, the study authors conclude that drug resistance is now common and widespread. They also say the study suggests that many HIV-positive people taking anti-HIV medications who have developed resistance to their medications are engaging in high-risk sex or needle sharing, which results in the new drug-resistant infections.
The study of 1,633 adults, the largest conducted to date on drug-resistant HIV, led some researchers to speculate that it might be wise to restrict access to some anti-HIV medications so that potent weapons against HIV will retain their effectiveness. For example, one researcher said the nonnucleoside reverse transcriptase inhibitor Viramune, often used to prevent mother-to-child HIV transmissions, might need to be restricted only for that use so resistance to it will not grow. Other conference attendees said better guidelines to suggest a preferred order in which doctors should treat their HIV-positive patients with specific drug regimens may be needed in order to prevent the widespread development of resistance to all anti-HIV medications.
The study authors say their findings also suggest that doctors should routinely screen all HIV-positive patients--particularly those who are newly infected--for drug resistance in order to craft the most potent anti-HIV drug cocktails possible. Drug resistance develops because HIV can rapidly mutate and make itself less vulnerable to anti-HIV drugs. It can occur fairly easily among patients who do not strictly adhere to their anti-HIV drug regimens, which can result in less than optimal levels of the drugs in the body, giving the virus an opportunity to mutate.