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HIV-1 seroconversion rates among female commercial sex workers, Chiang Mai, Thailand: a multi cross-sectional study
P Sawanpanyalert1, K Ungchusak, S Thanprasertsuk
1Division of Epidemiology, Department of Communicable Diseases Control, Ministry of Public Health, Bangkok, Thailand.
Insights
High HIV seroconversion rates were observed in Chiang Mai female commercial sex workers (CSW). Despite reported high condom use, aggressive education programs are needed to combat HIV and sexually transmitted diseases (STD) in Thailand.
Area of Science:
- Epidemiology
- Public Health
- Infectious Diseases
Background:
- Commercial sex workers (CSW) are a key population for HIV surveillance.
- Understanding HIV seroconversion rates is crucial for targeted prevention strategies.
- Previous studies have indicated varying HIV prevalence among CSW in Southeast Asia.
Purpose of the Study:
- To determine human immunodeficiency virus (HIV) seroconversion rates among female commercial sex workers (CSW) in Chiang Mai, Thailand.
- To assess the prevalence of sexually transmitted diseases (STD) within this population.
- To evaluate the effectiveness of reported condom use in preventing HIV transmission.
Main Methods:
- A three-round multi cross-sectional study was conducted at approximately 3-month intervals from December 1989 to July 1990.
- Random selection of 38 brothels in Chiang Mai, interviewing and testing 518, 431, and 320 female CSW in each round.
- Data collection included sociodemographics, sexual practices, condom use, STD history, and HIV-1 antibody testing. Gonorrhea testing was also performed.
Main Results:
- HIV seroconversion rates were 5.2% per woman-month (December-March) and 3.6% per woman-month (March-July).
- High reported condom use (85.8-91.8%) was observed among CSW.
- Significant prevalence of reported STD histories (71.6-77.0%) and positive gonorrhea cultures (11.2-12.3% cervical, 8.8-11.4% urethral) were found.
Conclusions:
- High HIV seroconversion rates persist despite high reported condom use among CSW in Chiang Mai.
- The findings suggest that current prevention measures, including condom use, may be insufficient.
- More aggressive and targeted education programs are urgently needed in Thailand to address HIV and STD transmission in this population.
Objectives:
To determine HIV seroconversion rates among female commercial sex workers (CSW) in Chiang Mai, Thailand.
Design:
A three-round multi cross-sectional study was used at approximately 3-month intervals.
Methods:
In December 1989, 38 brothels (60%) in Chiang Mai were randomly selected. All 518 female CSW in the brothels were interviewed about their sociodemographics, sexual practices, condom use, history of sexually transmitted diseases (STD) and other risk factors. Blood was tested for Venereal Disease Research Laboratory (VDRL)-reactivity and HIV-1 antibody. The same brothels, which were all still operating, were revisited in March and July 1990 and 431 and 320 CSW, respectively, were interviewed and blood-tested. Pelvic examination, cervical, urethral and rectal cultures for gonococcus were added to the study in March 1990, although rectal culture was dropped from the study in July 1990.
Results:
There were 5.2% [95% confidence interval (CI), 4.1-10.6] and 3.6% (95% CI, 1.5-5.4) per woman-month HIV seroconversion rates for the December-March and March-July periods, respectively. Of the CSW, 71.6-77.0% reported histories of at lest one STD. Condom-use rates among these CSW were reported to be 85.8-91.8%. High rates of positive cervical (11.2-12.3%) and urethral (8.8-11.4%) cultures for gonococcus were also found in the CSW.
Conclusions:
The fact that high HIV seroconversion rates and high STD prevalence rates occur despite high rates of reported condom use suggests that more aggressive education programs are needed in Thailand.
