How safe is safer sex? High levels of HSV-1 and HSV-2 in female sex workers in London.

Female sex workers in Europe have low levels of sexually transmitted infections, attributable to condom use. The aim of this paper is to describe the seroepidemiology of HSV-1 and HSV-2 in female sex workers in London by using a 15-year prospective study of 453 sex workers. The seroprevalence of HSV-1 was 74.4% and independently associated with birth in a 'transitional country' (OR 5.4, 95% CI 1.61-18.20). The seroprevalence of HSV-2 was 60% and declined over time; it was also independently associated with time in sex work (OR 2.12, 95% CI 1.23-3.65) and birth in a 'developing country' (OR 2.95, 95% CI 1.34-6.48). We show that a cohort of sex workers with extensive condom use and little known sexually transmitted infection have high levels of HSV-1 and HSV-2 infection, suggesting that condoms may not be universally protective. Sex workers are candidates for HSV vaccine efficacy or intervention studies.