Rural sex work in Cambodia: work characteristics, risk behaviours, HIV, and syphilis

To identify prevalence and risks factors for syphilis and HIV among rural female sex workers (FSWs) in Cambodia and to describe differences between rural and urban FSWs.

Interviews and sera were collected from 114 FSWs and tested for HIV using the Serodia-HIV test and positives confirmed with the enzyme linked immunosorbent assay. Syphilis was tested for with the rapid plasma reagin with passive particle agglutination test for detection of antibody of Treponema pallidum. Study data were merged with data from a study of urban FSWs from Phnom Penh that applied similar questionnaires and sampling design to compare STI prevalence and behaviours.

42% of rural FSWs were HIV positive; 22% had past or current syphilis. In multivariate models HIV was significantly associated with age > or = 25 (OR = 6.1 95% CI: 1.0 to 36.6), a non-commercial partner in the past year (OR= 0.33, 95% CI: 0.11 to 0.93), and prevalence of past or current syphilis (OR = 2.9, 95% CI: 1.0 to 8.8). There was significantly higher active syphilis (14% v 4%), older mean age (25 v 21), fewer daily clients (2 v 5), lower monthly income (61 US dollars v 174 US dollars), and longer duration of sex work (2.3 years v 1.4 years) among rural than among urban FSWs.

These findings reveal a high burden of HIV and syphilis among FSWs in rural Cambodia. As FSWs age and become infected with STI/HIV they may move out of cities into less competitive but less savvy markets; their high mobility may contribute to the expansion of the HIV epidemic into rural Cambodia and lower risk populations.