Male sex workers are significantly more likely to be diagnosed with certain sexually transmitted infections (STIs) than other men, surveillance data from English genitourinary medicine (GUM) clinics show. Male sex workers were three times more likely to be diagnosed with HIV or chlamydia and twice as likely to receive a gonorrhoea diagnosis compared to other men. Approximately a third of male sex workers were migrants, mainly from Brazil. The findings are published in the online edition of Sexually Transmitted Infections.

Little is known about the characteristics and sexual health of male sex workers in the UK, though they are thought to have a higher risk of STIs compared to other men. Differences in sexual health according to migration status have been observed in female sex workers, but this question has not been explored in male sex workers.

A team of investigators therefore analysed the electronic patient records of 627,780 men who attended sexual health services in England during 2011. These records provided data concerning sex work, age, migration status, sexuality and STI/HIV screening and diagnoses.

Glossary chlamydia Chlamydia is a common sexually transmitted infection, caused by bacteria called Chlamydia trachomatis. Women can get chlamydia in the cervix, rectum, or throat. Men can get chlamydia in the urethra (inside the penis), rectum, or throat. Chlamydia is treated with antibiotics. confounding Confounding exists if the true association between one factor (Factor A) and an outcome is obscured because there is a second factor (Factor B) which is associated with both Factor A and the outcome. Confounding is often a problem in observational studies when the characteristics of people in one group differ from the characteristics of people in another group. When confounding factors are known they can be measured and controlled for (see ‘multivariable analysis’), but some confounding factors are likely to be unknown or unmeasured. This can lead to biased results. Confounding is not usually a problem in randomised controlled trials. disclosure In HIV, refers to the act of telling another person that you have HIV. Many people find this term stigmatising as it suggests information which is normally kept secret. The terms ‘telling’ or ‘sharing’ are more neutral.

Overall, 488 (0.08%) of clinic attendees were identified as male sex workers. However, the investigators believe the true figure is likely to be higher, “due in part to a lack of disclosure. UK studies have reported that as few as one-third of SW [sex workers] disclose their status to healthcare workers.”

Male sex workers were slightly older than other male patients (median age, 29 vs 28 years; p = 0.05) and 30% of sex workers were aged over 35. The authors highlight how these findings are contrary to “assumptions that male sex workers [MSW] are a predominately younger group.”

The data further showed that male sex workers were also more likely than other men to be migrants (38 vs 19%; p < 0.001) and to identify as men who have sex with men (57 vs 15%; p < 0.001), yet the investigators were somewhat surprised at the low proportion identifying as men who have sex with men and suggest this finding warrants further investigation.

The migrant male sex workers reported 50 countries of origin, with 39% coming from South America (97% of these were from Brazil), 25% from Europe and 12% from eastern Europe. Sex workers who were migrants were twice as likely to identify as men who have sex with men compared to non-migrant male sex workers (77 vs 35%; p < 0.001).

Male sex workers visited clinics more often than other men (mean 4.5 vs 2.3 visits), and migrant male sex workers made more visits than UK-born sex workers (5 vs 4.4 visits; p = 0.03).

Overall 86% of male sex workers had a sexual health screen and 73% had an HIV test. The comparative figures for other men were 68 and 73%, respectively.

Rates of diagnoses of chlamydia were higher among male sex workers than other men (25 vs 10%; p < 0.001), as were rates of gonorrhoea (17 vs 3%; p < 0.001) and HIV diagnoses (4 vs 0.6%; p < 0.001).

After adjusting for confounding factors such as age and sexual orientation, male sex workers were over three times more likely to be diagnosed with HIV (OR = 3.37; 95% CI, 1.86-6.02; p < 0.001) compared to other men, and also approximately three times more likely to receive a chlamydia diagnosis (p < 0.001) and twice as likely to be diagnosed with gonorrhoea (p < 0.001). Migrant male sex workers were more likely than non-migrant sex workers to be diagnosed with chlamydia (OR = 2.2; 95% CI, 1.08-4.49; p = 0.03).

Male sex workers were also significantly more likely to re-present with chlamydia and gonorrhoea than other groups of men (9 vs 4%; 14 vs 5%).

“Our study provides a national picture of the comparative sexual health and service use of [male sex workers] attending GUM clinics,” conclude the authors.