Possible reasons for an increase in the proportion of genital ulcers due to herpes simplex virus from a cohort of female bar workers in Tanzania
- Gabriele Riedner1,
- Jim Todd1,
- Mary Rusizoka2,
- Donan Mmbando2,
- Leonard Maboko5,
- Eligius Lyamuya3,
- Oliver Hoffmann4,
- I MacLean6,
- Heiner Grosskurth1,
- Richard Hayes1
- 1London School of Hygiene & Tropical Medicine, London, UK
- 2Regional Medical Office, Mbeya, Tanzania
- 3Muhimbili University College of Health Sciences, Dar es salaam, Tanzania
- 4Department of Infectious Diseases and Tropical Medicine, Ludwig-Maximilians-University, Munich, Germany
- 5Mbeya Medical Research Programme, Mbeya, Tanzania
- 6Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
- Correspondence to: Dr G Riedner WHO Regional Office for the Eastern Mediterranean, Adul Razzak Al-Sanhouri St, PO Box 7068 Nasr City, Cairo 11371, Egypt;
- Accepted 4 September 2006
- Published Online First 13 September 2006
Objectives: To determine trends in the prevalence and aetiological distribution of genital ulcer syndrome (GUS) in a cohort of female bar workers and to assess factors associated with these trends.
Methods: An open cohort of 600 women at high risk of HIV and sexually transmitted infection (STI) was offered screening and treatment for STI at 3-month intervals. The prevalence of GUS and associated aetiological agents (Herpes simplex virus (HSV), Treponema pallidum and Haemophilus ducreyi) were monitored over 27 months through clinical examination, dry lesion swabbing and multiplex polymerase chain reaction. The effects of HIV status and other factors on the prevalence trends of STI were assessed.
Results: A total of 753 women were recruited into the cohort over 10 examination rounds. At recruitment, the seroprevalence was 67% for HIV and 89% for HSV type 2 (HSV-2). During follow-up, 57% of ulcers had unknown aetiology, 37% were due to genital herpes and 6% to bacterial aetiologies, which disappeared completely in later rounds. The absolute prevalence of genital herpes remained stable at around 2%. The proportion of GUS caused by HSV increased from 22% to 58%, whereas bacterial causes declined. These trends were observed in both HIV-negative and HIV-positive women.
Conclusions: The changes observed in the frequency and proportional distribution of GUS aetiologies suggest that regular STI screening and treatment over an extended period can effectively reduce bacterial STI and should therefore be sustained. However, in populations with a high prevalence of HSV-2, there remains a considerable burden of genital herpes, which soon becomes the predominant cause of GUS. Given the observed associations between genital herpes and HIV transmission, high priority should be given to the evaluation of potential interventions to control HSV-2 either through a vaccine or through episodic or suppressive antiviral therapy and primary prevention.
- GUS, genital ulcer syndrome
- HSV, herpes simplex virus
- HSV-2, herpes simplex virus type 2
- PCR, polymerase chain reaction
- STI, sexually transmitted infection
Published Online First 13 September 2006
GR was involved in the study design, field data collection, data analysis and manuscript writing; JT in data analysis and manuscript writing; MR in field data collection and manuscript revision; DM in study design, field data collection and manuscript revision; LM in field data collection and manuscript revision; EL in study design and manuscript revision; OH in field data collection and manuscript revision; IM in study design, laboratory data and manuscript revision; HG in study design, field data collection and manuscript revision; RH in study design, field data collection, data analysis and manuscript writing.
Funding: This work was supported through a Research Training Fellowship of the Wellcome Trust, UK, and a grant by the European Commission, DG XII, INCO-DC, ICA-CT-1999–10007.
Competing interests: None declared.