Gay Men Found To Have Gonorrhoea In The Throat More Frequently

Gay men should have regular throat swabs to check for infection with gonorrhoea, American investigators emphasise after a study conducted in San Francisco found that 6% of gay men had the sexually transmitted infection in their throat, usually without any symptoms. The study, which is published in the November 15th edition of Clinical Infectious Diseases (now on-line) also found that the throat was the most common site for gonorrhoea infection in gay men and that younger age and a greater number of oral sex partners were significantly associated with gonorrhoea of the throat.
The US Centers for Disease Control reported that in 2003 the prevalence of gonorrhoea amongst gay men was 15%. Earlier studies looking at the prevalence of pharyngeal gonorrhoea – gonorrhoea of the throat – amongst gay men have found a prevalence of between 3% - 15%. However, there are a lack of longitudinal data from an on-going cohort of gay men looking at the prevalence, incidence and risk factors for gonorrhoea infection in the throat.
Investigators from the EXPLORE study in San Francisco therefore performed gonorrhoea tests on 603 gay men at baseline and then at six-monthly intervals. Swabs were taken from the throat, penis and rectum. The men were also asked to provide demographic information and details of their recent sexual risk behaviour.
To be included in the study, the men had to be HIV-negative at baseline. The mean age was 36 years, 71% were white, 72% had completed secondary education or higher, and over two-thirds had an annual income of $30,000 or more.
At baseline, 5% had gonorrhoea in the throat, and 18% of individuals had at least one episode of gonorrhoea of the throat during the course of the study. Of the individuals who became HIV-positive during follow-up, 21% had at least one episode of gonorrhoea of the throat.
Overall prevalence of pharyngeal gonorrhoea was 6%, compared to 2% for rectal gonorrhoea and 1% for urethral gonorrhoea. There were 943 person-years of observation available for the investigators’ analysis and they determined that the incidence of gonorrhoea of the throat was 11 per 100 person years, compared to 4 cases per 100 person years for rectal gonorrhorea and 2 cases per 100 person years for gonorrhoea infection in the urethra.
In their initial analysis, the investigators found that performing sex on a man known to be HIV-positive, a greater number of oral sex partners and younger age were all significantly associated with gonorrhoea of the throat. However, in multivariate analysis, only younger age (under 44-years, p < 0.05), and performing oral sex on five or more men (p < 0.05) remained significant.
A sore throat was not predictive of pharyngeal gonorrhoea meaning that in most cases gonorrhoea infection in the throat was asymptomatic.
Although gonorrhoea in the throat clears without treatment in 50% of cases within one week and in all cases within three months, the investigators emphasise that the high prevalence of the infection found in their study demonstrates that the throat acts as a “reservoir” for gonorrhoea transmission amongst gay men. They therefore recommend that all sexually gay men should have a throat swab to check for gonorrhoea in the throat annually, and that gay men who have multiple or anonymous partners should have such swabs every three to six months.
from AIDS Map