Official websites use. Share sensitive information only on official, secure websites. Competing Interests: The authors have declared that no competing interests exist. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. Four groups of HIV seropositive adult female barworkers were identified and examined at three-monthly intervals between October and March in Mbeya, Tanzania: 1 57 women at 70 clinic visits with clinical genital herpes; 2 39 of the same women at 46 clinic visits when asymptomatic; 3 55 HSV-2 seropositive women at 60 clinic visits who were never observed with herpetic lesions; 4 18 HSV-2 seronegative women at 45 clinic visits.
In paired specimens from HSV-2 positive women, genital HIV viral shedding was similar during symptomatic and asymptomatic visits. Herpes simplex virus type-2 HSV-2 infection is lifelong and a common cause of genital ulcers [1] β [3]. In vitro studies provide evidence of the effect of HSV-2 infection on HIV replication [7] β [9] and epidemiological studies link acute episodes of genital herpes to temporal increases in HIV plasma viral load [10].
Observational studies have shown an association between HSV-2 genital shedding and HIV genital shedding in some cases but not others [12] β [15]. The frequency of recurrent episodes of clinical herpes and of subclinical viral shedding varies both between individuals and over time within the same individual [24] , [25].
While research supports an association between HSV infection and HIV shedding, it is less clear whether any effect on HIV infectivity is restricted primarily to clinical episodes of genital herpes or if HIV transmission is also enhanced during asymptomatic HSV-2 infection [26].
As part of a study of the determinants of HIV super-infection in Mbeya Region, Tanzania, an open cohort of female barworkers aged 18 to 35 years was established in late Study procedures have been described previously [28]. Briefly, behavioural and biological data were collected at baseline and during 3-monthly follow-up visits for up to 30 months. In this paper we present data collected from HIV infected participants between October and March Cervicovaginal secretions CVS were collected from all women at every study visit using standard vaginal lavage procedures [30] , by washing with 5 ml of phosphate-buffered saline.
