Souleymane Diabaté

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

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.

Violence condom breakage and HIV infection among female sex workers in Benin West Africa.

Objective To examine the relationship between violence, condom breakage, and HIV prevalence among female sex workers (FSWs). Methods Data were obtained from the 2012 cross-sectional integrated biological and behavioral survey conducted in Benin. Multivariable log-binomial regression was used to estimate the adjusted prevalence ratios of HIV infection and condom breakage in relation to violence toward FSWs. A score was created to examine the relationship between the number of violence types reported and HIV infection. Results Among the 981 women who provided a blood sample, HIV prevalence was 20.4%. During the last month, 17.2%, 13.5%, and 33.5% of them had experienced physical, sexual, and psychological violence, respectively. In addition, 15.9% reported at least 1 condom breakage during the previous week. There was a significant association between all types of violence and HIV prevalence. The adjusted prevalence ratios of HIV were 1.45 (95% confidence interval [95% CI], 1.05–2.00), 1.42 (95% CI, 1.02–1.98), and 1.41 (95% CI, 1.08–1.41) among those who had ever experienced physical, sexual, and psychological violence, respectively. HIV prevalence increased with the violence score (P = 0.002, test for trend), and physical and sexual violence were independently associated with condom breakage (P = 0.010 and P = 0.003, respectively). Conclusions The results show that violence is associated with a higher HIV prevalence among FSWs and that condom breakage is a potential mediator for this association. Longitudinal studies designed to analyze this relationship and specific interventions integrated to current HIV prevention strategies are needed to reduce the burden of violence among FSWs.

Assessment of HIV-related risky behaviour: a comparative study of face-to-face interviews and polling booth surveys in the general population of Cotonou, Benin

Objectives During the 2008 HIV prevalence survey carried out in the general population of Cotonou, Benin, face-to-face interviews (FTFI) were used to assess risky behaviours for HIV and other sexually transmitted infections (STI). We compared sexual behaviours reported in FTFI with those reported in polling booth surveys (PBS) carried out in parallel in an independent random sample of the same population. Methods In PBS, respondents grouped by gender and marital status answered simple questions by putting tokens with question numbers in a green box (affirmative answers) or a red box (negative answers). Both boxes were placed inside a private booth. For each group and question, data were gathered together by type of answer. The structured and gender-specific FTFI guided by trained interviewers included all questions asked during PBS. Pearson χ2 or Fishers exact test was used to compare FTFI and PBS according to affirmative answers. Results Overall, respondents reported more stigmatised behaviours in PBS than in FTFI: the proportions of married women and men who reported ever having had commercial sex were 17.4% and 41.6% in PBS versus 1.8% and 19.6% in FTFI, respectively. The corresponding proportions among unmarried women and men were 16.1% and 25.5% in PBS versus 3.9% and 13.0% in FTFI, respectively. The proportion of married women who reported having had extramarital sex since marriage was 23.6% in PBS versus 4.6% in FTFI. Conclusions PBS are suitable to monitor reliable HIV/STI risk behaviours. Their use should be expanded in behavioural surveillance.

Abolishing Fees at Health Centers in the Context of Community Case Management of Malaria: What Effects on Treatment-Seeking Practices for Febrile Children in Rural Burkina Faso?

Introduction Burkina Faso started nationwide community case management of malaria (CCMm) in 2010. In 2011, health center user fees for children under five were abolished in some districts. Objective To assess the effects of concurrent implementation of CCMm and user fees abolition on treatment-seeking practices for febrile children. Methods This is a natural experiment conducted in the districts of Kaya (CCMm plus user fees abolition) and Zorgho (CCMm only). Registry data from 2005 to 2014 on visits for malaria were collected from all eight rural health centers in the study area. Annual household surveys were administered during malaria transmission season in 2011 and 2012 in 1,035 randomly selected rural households. Interrupted time series models were fitted for registry data and Fine and Gray’s competing risks models for survey data. Results User fees abolition in Kaya significantly increased health center use by eligible children with malaria (incidence rate ratio for intercept change = 2.1, p <0.001). In 2011, in Kaya, likelihood of health center use for febrile children was three times higher and CHW use three times lower when caregivers knew services were free. Among the 421 children with fever in 2012, the delay before visiting a health center was significantly shorter in Kaya than in Zorgho (1.46 versus 1.79 days, p <0.05). Likelihood of visiting a health center on the first day of fever among households <2.5km or <5 km from a health center was two and three times higher in Kaya than in Zorgho, respectively (p <0.001). Conclusions User fees abolition reduced visit delay for febrile children living close to health centers. It also increased demand for and use of health center for children with malaria. Concurrently, demand for CHWs’ services diminished. User fees abolition and CCMm should be coordinated to maximize prompt access to treatment in rural areas.

Decline in HIV prevalence among young men in the general population of Cotonou, Benin, 1998-2008.

Objective To assess changes in the prevalence of HIV and other sexually transmitted infections, as well as in different proximal and distal factors related to HIV infection, in the general population of Cotonou between 1998 and 2008, while an intensive preventive intervention targeting the sex work milieu was ongoing. Methods A two-stage cluster sampling procedure was used to select the participants in each study. Subjects aged 15–49 who agreed to participate were interviewed and tested for HIV, syphilis, HSV-2, gonorrhoea and chlamydia. We used the Roa-Scott Chi-square test (proportions) and the Student’s t test (means) for bivariate comparisons, and adjusted logistic regression models taking into account the cluster effect for multivariate analyses. Results HIV prevalence decreased significantly in men (3.4% in 1998 versus 2.0% in 2008, p = 0.048), especially in those aged 15–29 (3.0% to 0.5%, p = 0.002). Among men, the prevalence of gonorrhoea decreased significantly (1.1% to 0.3%, p = 0.046) while HSV-2 prevalence increased from 12.0% to 18.1% (p = 0.0003). The proportion of men who reported condom use at least once (29.3% to 61.0%, p<0.0001) and of those having attained a secondary educational level or more (17.1% to 61.3%, p<0.0001) also increased significantly. There was an overall decrease in the prevalence of syphilis (1.5% to 0.6%, p = 0.0003). Conclusion This is the first population-based study reporting a significant decline in HIV prevalence among young men in an African setting where overall prevalence has never reached 5%. The decline occurred while preventive interventions targeting the sex work milieu were ongoing and the educational level was increasing.

Changing Dynamics of Hiv Transmission in Côte d'ivoire: Modeling Who Acquired and Transmitted Infections and Estimating the Impact of Past Hiv Interventions (1976–2015)

Introduction: Understanding the impact of past interventions and how it affected transmission dynamics is key to guiding prevention efforts. We estimated the population-level impact of condom, antiretroviral therapy (ART), and prevention of mother-to-child transmission activities on HIV transmission and the contribution of key risk factors on HIV acquisition and transmission. Methods: An age-stratified dynamical model of sexual and vertical HIV transmission among the general population, female sex workers (FSW), and men who have sex with men was calibrated to detailed prevalence and intervention data. We estimated the fraction of HIV infections averted by the interventions, and the fraction of incident infections acquired and transmitted by different populations over successive 10-year periods (1976–2015). Results: Overall, condom use averted 61% (95% credible intervals: 56%–66%) of all adult infections during 1987–2015 mainly because of increased use by FSW (46% of infections averted). In comparison, ART prevented 15% (10%–19%) of adult infections during 2010–2015. As a result, FSW initially (1976–1985) contributed 95% (91%–97%) of all new infections, declining to 19% (11%–27%) during 2005–2015. Older men and clients mixing with non-FSW are currently the highest contributors to transmission. Men who have sex with men contributed ⩽4% transmissions throughout. Young women (15–24 years; excluding FSW) do not transmit more infections than they acquired. Conclusions: Early increases in condom use, mainly by FSW, have substantially reduced HIV transmission. Clients of FSWs and older men have become the main source of transmission, whereas young women remain at increased risk. Strengthening prevention and scaling-up of ART, particularly to FSW and clients of female sex workers, is important.

Population-level impact of an accelerated HIV response plan to reach the UNAIDS 90-90-90 target in Côte d’Ivoire: Insights from mathematical modeling

Background National responses will need to be markedly accelerated to achieve the ambitious target of the Joint United Nations Programme on HIV/AIDS (UNAIDS). This target aims for 90% of HIV-positive individuals to be aware of their status, for 90% of those aware to receive antiretroviral therapy (ART), and for 90% of those on treatment to have a suppressed viral load by 2020, with each individual target reaching 95% by 2030. We aimed to estimate the impact of various treatment-as-prevention scenarios in Côte d’Ivoire, one of the countries with the highest HIV incidence in West Africa, with unmet HIV prevention and treatment needs, and where key populations are important to the broader HIV epidemic. Methods and findings An age-stratified dynamic model was developed and calibrated to epidemiological and programmatic data using a Bayesian framework. The model represents sexual and vertical HIV transmission in the general population, female sex workers (FSW), and men who have sex with men (MSM). We estimated the impact of scaling up interventions to reach the UNAIDS targets, as well as the impact of 8 other scenarios, on HIV transmission in adults and children, compared to our baseline scenario that maintains 2015 rates of testing, ART initiation, ART discontinuation, treatment failure, and levels of condom use. In 2015, we estimated that 52% (95% credible intervals: 46%–58%) of HIV-positive individuals were aware of their status, 72% (57%–82%) of those aware were on ART, and 77% (74%–79%) of those on ART were virologically suppressed. Reaching the UNAIDS targets on time would avert 50% (42%–60%) of new HIV infections over 2015–2030 compared to 30% (25%–36%) if the 90-90-90 target is reached in 2025. Attaining the UNAIDS targets in FSW, their clients, and MSM (but not in the rest of the population) would avert a similar fraction of new infections (30%; 21%–39%). A 25-percentage-point drop in condom use from the 2015 levels among FSW and MSM would reduce the impact of reaching the UNAIDS targets, with 38% (26%–51%) of infections averted. The study’s main limitation is that homogenous spatial coverage of interventions was assumed, and future lines of inquiry should examine how geographical prioritization could affect HIV transmission. Conclusions Maximizing the impact of the UNAIDS targets will require rapid scale-up of interventions, particularly testing, ART initiation, and limiting ART discontinuation. Reaching clients of FSW, as well as key populations, can efficiently reduce transmission. Sustaining the high condom-use levels among key populations should remain an important prevention pillar.

Impact of contaminated household environment on stunting in children aged 12–59 months in Burkina Faso

Background Stunting affects 165 million children worldwide, with repercussions on their survival and development. A contaminated environment is likely to contribute to stunting: frequent faecal-oral transmission possibly causes environmental enteropathy, a chronic inflammatory disorder that may contribute to faltering growth in children. This studys objective was to assess the effect of contaminated environment on stunting in Burkina Faso, where stunting prevalence is persistently high. Methods Panel study of children aged 1–5 years in Kaya. Household socioeconomic characteristics, food needs and sanitary conditions were measured once, and child growth every year (2011–2014). Using multiple correspondence analysis and 12 questions and observations on water, sanitation, hygiene behaviours, yard cleanliness and animal proximity, we constructed a ‘contaminated environment’ index as a proxy of faecal-oral transmission exposure. Analysis was performed using a generalised structural equation model (SEM), adjusting for repeat observations and hierarchical data. Results Stunting (<2 SD height-for-age) prevalence was 29% among 3121 children (median (IQR) age 36 (25–48) months). Environment contamination was widespread, particularly in rural and peri-urban areas, and was associated with stunting (prevalence ratio 1.30; p=0.008), controlling for sex, age, survey year, setting, mothers education, fathers occupation, household food security and wealth. This association was significant for children of all ages (1–5 years) and settings. Lower contamination and higher food security had effects of comparable magnitude. Conclusions Environment contamination can be at least as influential as nutritional components in the pathway to stunting. There is a rationale for including interventions to reduce environment contamination in stunting prevention programmes.

Domestic Larval Control Practices and Malaria Prevalence among Under-Five Children in Burkina Faso

Introduction Larval source management has contributed to malaria decline over the past years. However, little is known about the impact of larval control practices undertaken at the household level on malaria transmission. Methods The study was conducted in Kaya health district after the 2010 mass distribution of insecticide treated-nets and the initiation of malaria awareness campaigns in Burkina Faso. The aim was to (i) estimate the level of domestic larval control practices (cleaning of the house and its surroundings, eradication of larval sources, and elimination of hollow objects that might collect water); (ii) identify key determinants; and (iii) explore the structural relationships between these practices, participation in awareness-raising activities and mothers’ knowledge/attitudes/practices, and malaria prevalence among under-five children. Results Overall, 2004 households were surveyed and 1,705 under-five children were examined. Half of the mothers undertook at least one action to control larval proliferation. Mothers who had gone to school had better knowledge about malaria and were more likely to undertake domestic larval control practices. Living in highly exposed rural areas significantly decreased the odds of undertaking larval control actions. Mothers’ participation in malaria information sessions increased the adoption of vector control actions and bednet use. Malaria prevalence was statistically lower among children in households where mothers had undertaken at least one vector control action or used bed-nets. There was a 0.16 standard deviation decrease in malaria prevalence for every standard deviation increase in vector control practices. The effect of bednet use on malaria prevalence was of the same magnitude. Conclusion Cleaning the house and its surroundings, eradicating breeding sites, and eliminating hollow objects that might collect water play a substantial role in preventing malaria among under-five. There is a need for national malaria control programs to include or reinforce training activities for community health workers aimed at promoting domestic larval control practices.

Gonorrhea, Chlamydia and HIV incidence among female sex workers in Cotonou, Benin: A longitudinal study

Female sex workers (FSWs) continue to carry a heavy burden of sexually transmitted infections (STI). For prevention purposes, there is a need to identify most-at-risk subgroups among them. The objective of this longitudinal cohort study conducted at Dispensaire IST, Cotonou, Benin, was to assess Neisseria gonorrhoeae (NG) / Chlamydia trachomatis (CT) incidence and determinants; and HIV incidence among FSWs in presence of STI/HIV risk reduction activities. Overall, 319 adult FSWs were followed quarterly from September 2008 to March 2012. NG/CT were detected from endocervical swabs by Amplified DNA Assays employing Strand displacement amplification technology. HIV testing was done on capillary blood using two consecutive rapid diagnostic tests. Anderson-Gill proportional hazard models (HR) were used to determine factors independently associated with NG/CT incidence. The majority of FSWs were HIV-negative (188, 58.9%). There were 6 HIV seroconversions among these 188 HIV-negative women. HIV incidence (95% Confidence interval, CI) was 1.41 (0.28–2.54) seroconversions per 100 person-years at risk (PYAR): 6 events / 425.1 PYAR. Sixty-two out of 319 women experienced 83 new episodes of NG/CT for an overall incidence rate (95% CI) of 10.8 (8.17–13.88) events / 100 PYAR. From month-24 onwards, HIV-positive women (treated: HR (95%CI): 4.2 (1.60–10.77); untreated: HR (95%CI): 4.2 (1.59–11.49) were more likely to acquire NG/CT compared to HIV-negative FSWs. Longer duration in sex work (>2 years: HR; 95%CI: 0.4 (0.22–0.72)) was protective against NG/CT. Refusal by clients (55.8%) was the main reason for non-condom use. Enrolling women from one clinic (Dispensaire IST) may have impaired generalizability of the findings. New NG/CT/HIV infections were observed among FSWs notwithstanding ongoing prevention interventions. To eliminate HIV transmission among FSWs, STI/HIV control programs need to promote women’s empowerment and address vulnerability to infection of HIV-positive FSWs.