The rates of Trichomonas vaginalis in the United States are lower in men than women, according to research published in Clinical Infectious Diseases. Infections in men were strongly associated with black race, HSV-2 infections, and other factors known to increase sexually transmitted infection (STI) rates.
Investigators used the National Health and Nutrition Examination Survey (NHANES) database to survey US men age 18 to 59 from 2013 to 2016. Demographic factors and information on other STIs were recorded, as were urine tests for Trichomonas vaginalis via polymerase chain reaction.
Overall rate of infection in the sample of 3764 men was 0.49%. There were no associations between infection and age, but the rate was higher in black men at 3.6%.
Sexual behaviors associated with higher rates of Trichomonas vaginalis infection were age at first sexual intercourse, number of lifetime sexual partners, and condom use.
The prevalence of HIV, HSV-1, and chlamydia infections was higher in men with Trichomonas vaginalis infection but not significantly different than in men without. However, prevalence of HSV-2 was higher in infected men than uninfected men at 49.6% vs 8.7%, respectively (odds ratio, 10.3; P <.00001).
The rates found in this study were lower than previous estimates, which could be a reflection of the NHANES program sampling design. The low prevalence rates also meant multivariable analysis was not performed. NHANES also only surveys non-institutionalized participants and rates are likely higher in institutionalized populations.
The study did include a robust sample of 3000 men and provided population level data. Therefore, the results identify a targetable population for control and treatment “to possibly limit associated morbidity and re-infection of sexual partners.”
The data may also be useful in the counselling, screening, and management of patients.
Daugherty M, Glynn K, Byler T. The prevalence of Trichomonas vaginalis infection among US males, 2013-2016 [published online June 9 2018]. Clin Infect Dis. doi: 10.1093/cid/ciy499