Scientists have reported several U.S. outbreaks of methicillin-resistant Staphyloccocus aureus (MRSA) infections among HIV-positive people during the past 18 months, and now researchers say risk for the infection in HIV patients is linked with HIV viral levels and CD4-cell counts. A study presented at the 12th Conference on Retroviruses and Opportunistic Infections in Boston shows that of 3,455 HIV-positive people studied from January 1, 2000, through December 31, 2003, 94 acquired drug-resistant staph infections. More than 80% of the infections were in soft skin tissues, with about 10% in the blood, and the rest in other parts of the body.
Further analysis showed that most of the cases were reported in HIV patients with CD4-cell counts below 50 cells, with high HIV viral loads, or both. The researchers say that risk for drug-resistant staph among such HIV patients increased sixfold over the four-year study period. "The association between clinically significant MRSA and HIV viral load, and its effect on modification by CD4 [cells], is previously unreported and suggests a direct effect of HIV on anti-staphylococcal defenses," the researchers write in their abstract presented at the Boston conference.
Outbreaks of drug-resistant staph infections have been reported among gay and bisexual men since late 2002, with documented cases reported in Los Angeles, San Francisco, Boston, Atlanta, New York City, Houston, and Washington, D.C. Most of those cases were HIV-positive men. Staph infections can be transmitted by skin-to-skin contact, including through sexual activity. The infections also can be spread at health clubs and saunas. The standard antibiotic drugs used to treat staph infections are inadequate against the strain of bacteria causing the outbreaks, and stronger, newer drugs must be used in their place. In some cases, patients have had to be hospitalized to receive intravenous antibiotics. There have been no reported deaths linked to the drug-resistant infections, but staph can be fatal if left untreated.
Staph infections cause large, painful sores on the skin. Because many of the gay men treated for the condition in the cities reporting recent outbreaks had the sores on their buttocks, scrota, penises, and upper thighs, health officials believe most of the infections were passed through sexual activity.
A fact sheet available from the Centers for Disease Control and Prevention recommends as the best steps to avoid staph infections: regular hand washing with soap and water, keeping cuts and abrasions covered until healed, using a moisturizer on dry skin to prevent cracking, and avoiding contact with other people's wounds or material that touched their wounds.