Decline in the prevalence of HIV and sexually transmitted infections among female sex workers in Benin over 15 years of targeted interventions

Abstract

Background: An HIV-preventive intervention targeting the sex work milieu and involving fully integrated components of structural interventions, communication for behavioral change and care for sexually transmitted infections (STIs), was implemented in Benin by a Canadian project from 1992 to 2006. It first covered Cotonou before being extended to other main cities from 2000. At the project end, the Beninese authorities took over the intervention, but structural interventions were interrupted and other intervention components were implemented separately. We estimated time trends in HIV/STI prevalence among female sex workers (FSWs) from 1993 to 2008 and assessed the impact of the change in intervention model on trends.

Methods: Six integrated biological and behavioral surveys were carried out among FSWs. Time trend analysis controlled for potential sociodemographic confounders using log-binomial regression.

Results: In Cotonou, from 1993 to 2008, there was a significant decrease in HIV (53.3%-30.4%), gonorrhea (43.2%-6.4%), and chlamydia (9.4%-2.8%) prevalence (all adjusted P = 0.0001). The decrease in HIV and gonorrhea prevalence was also significant in the other cities between 2002 and 2008. In 2002, gonorrhea prevalence was lower in Cotonou than elsewhere (prevalence ratio = 0.53, 95% confidence interval: 0.32 to 0.88). From 2005 to 2008, there was an increase in gonorrhea prevalence (prevalence ratio = 1.76, 95% confidence interval: 1.17 to 2.65) in all cities combined.

Conclusions: Our results suggest a significant impact of this targeted preventive intervention on HIV/STI prevalence among FSWs. The recent increase in gonorrhea prevalence could be related to the lack of integration of the intervention components.

Figure 1. Time trends in reported consistent condom use (A) and in HIV/gonorrhea/chlamydia prevalence (B) among female sex workers in Benin, 1993–2008

A. After the beginning of the Canadian International Development Agency (CIDA) preventive project in Cotonou (vertical full arrow) and in Porto-novo, Abomey, Bohicon and Parakou (O/Cotonou, vertical dotted arrow), the proportion of FSW who reported consistent condom use with their clients in the previous month increased significantly in Cotonou (p-trend<0.0001, univariate analysis) and remained stable O/Cotonou (p-trend=0.903, univariate analysis). B. In Cotonou, HIV, gonorrhea and chlamydia prevalence decreased significantly after the beginning of the project (p-trend<0.0001, univariate analysis). O/Cotonou, there was also a significant decline in HIV and gonorrhea prevalence (p-trend<0.0001).