HIV Weekly - 17th July 2013

A round-up of the latest HIV news, for people living with HIV in the UK and beyond.

Rates of unprotected sex among European gay men

A large internet-based survey has found high rates of unprotected sex among European gay men. Overall, 58% of participants reported unprotected anal sex in the previous year.

The survey was conducted in 2010 and involved 180,000 gay and other men who have sex with men (MSM) across Europe.

Gay men are one of the groups most affected by HIV in Europe. The overwhelming majority of sexually acquired HIV infections among gay men can be attributed to unprotected anal sex.

Researchers therefore wanted to see how common unprotected anal sex was among European gay men and if there were any factors associated with having anal sex without condoms.

Overall, 58% of sexually active men reported unprotected sex with another man in the previous twelve months.

The researchers analysed rates of unprotected sex according to whether this was with a steady or a casual partner.

Unprotected anal sex was reported by 67% of men with a steady partner. In 78% of cases, unprotected sex occurred with a partner of the same HIV status.

Turning to men with a casual partner, the researchers found that almost 40% reported unprotected anal sex. A quarter of men reporting unprotected sex with a casual partner said that this was with a man of unknown or different HIV status.

Men in eastern European countries were more likely to have had unprotected anal sex with a partner of unknown or different HIV status than men in western Europe.

Younger men and those with less education were the groups most likely to report unprotected sex with a steady partner.

Men living with HIV were the group most likely to have had unprotected sex with a casual partner, and 53% did not discuss their HIV status with their partners.

The investigators believe their research has highlighted some HIV prevention priorities. These include:

  • Mutual HIV testing for men in steady relationships having unprotected sex.
  • Work supporting men to disclose their HIV status.

Several other reports on aidsmap.com describe other findings from the European Men Who Have Sex with Men Internet Survey (EMIS). Find out more on our EMIS feature page >>

HPV vaccination for gay men

Vaccination against the human papillomavirus (HPV) provides older gay men with protection against HPV strains associated with a high risk of anal cancer, Australian research shows.

Vaccines are available that provide a high degree of protection against the strains of HPV associated with the highest risk of ano-genital cancers.

The most widely used vaccine is Gardasil. This provides protection against HPV strains 6, 11, 16 and 18.

In Australia, roll-out of HPV vaccination was initially targeted at school-age girls. Since 2013, it has also been available for boys.

Some researchers have questioned whether it is worth vaccinating individuals after they become sexually active. This is because the vaccine doesn’t provide protection against an HPV strain if the person being vaccinated already has this strain.

Gay men have high rates of ano-genital warts and the incidence of anal cancer is higher among gay men living with HIV than any other group. Nevertheless, HPV vaccination is not routinely available to adult gay men.

The researchers wanted to see if use of Gardasil (or an experimental vaccine currently under development that provides protection against nine high-risk HPV strains) would prevent new infections with cancer-associated HPV types in older gay men.

Their study involved 342 gay men aged 35 and older. At the start of the study, the men were screened for infection with HPV strains covered by Gardasil and the experimental vaccine.

The men had an average age of 49 and 29% were living with HIV. On entry to the study, 51% had anal infection with an HPV strain covered by Gardasil and two-thirds with a type of the virus prevented by the experimental vaccine.

The study participants were monitored for three years. Each year, approximately a fifth of men were infected with a new HPV type covered by Gardasil and over a quarter with a strain preventable with the experimental vaccine.

The researchers therefore conclude that vaccination with either Gardasil or the experimental vaccine would prevent HPV-related disease in gay men older than 35.

Nevirapine rash

Genetic testing can predict which patients are likely to develop the severe skin rash that can be a side-effect of the non-nucleoside reverse transcriptase inhibitor (NNRTI) nevirapine (Viramune).

Side-effects are a major limitation of nevirapine. In a small number of people, treatment with the drug can cause a hypersensitivity reaction involving a serious – and in some instances life-threatening – rash.

The risk of this rash means women with a CD4 cell count above 250 and men with a CD4 cell count above 400 should not start therapy with nevirapine.

Now researchers have found that testing for two particular genes can help identify the people most at risk of nevirapine rash.

Two genetic variations (HLA-B*35:05 and CCHCR1 SNPs) have been associated with this increased risk.

Researchers in Thailand designed a study involving approximately 1100 people starting HIV treatment. Approximately half were screened for these genes. If the genes were detected, the patients were treated with efavirenz (Sustiva, Stocrin) instead of nevirapine.

Overall, 3% of participants were positive for HLA-B*35:05, 14% for CCHCR1 and 3% for both.

Screening, and tailoring therapy accordingly, reduced the rate of serious rash by a third. Screening was especially valuable for women, reducing the risk of rash by 45%, with a 36% reduction seen in women with a CD4 cell count below 250.

The findings of this research need to be confirmed in other populations where the genes associated with nevirapine rash are more common.

Testing for a gene associated with an allergic reaction to abacavir (Ziagen, also in Kivexa) is already routine when treatment with this drug is being considered.