Mathematical Model Impact Analysis of a Real-Life Pre-exposure Prophylaxis and Treatment-As-Prevention Study Among Female Sex Workers in Cotonou, Benin

BACKGROUND

Daily pre-exposure prophylaxis (PrEP) and treatment-as-prevention (TasP) reduce HIV acquisition and transmission risk, respectively. A demonstration study (2015-2017) assessed TasP and PrEP feasibility among female sex workers (FSW) in Cotonou, Benin.

SETTING

Cotonou, Benin.

METHODS

We developed a compartmental HIV transmission model featuring PrEP and antiretroviral therapy (ART) among the high-risk (FSW and clients) and low-risk populations, calibrated to historical epidemiological and demonstration study data, reflecting observed lower PrEP uptake, adherence and retention compared with TasP. We estimated the population-level impact of the 2-year study and several 20-year intervention scenarios, varying coverage and adherence independently and together. We report the percentage [median, 2.5th-97.5th percentile uncertainty interval (95% UI)] of HIV infections prevented comparing the intervention and counterfactual (2017 coverages: 0% PrEP and 49% ART) scenarios.

RESULTS

The 2-year study (2017 coverages: 9% PrEP and 83% ART) prevented an estimated 8% (95% UI 6-12) and 6% (3-10) infections among FSW over 2 and 20 years, respectively, compared with 7% (3-11) and 5% (2-9) overall. The PrEP and TasP arms prevented 0.4% (0.2-0.8) and 4.6% (2.2-8.7) infections overall over 20 years, respectively. Twenty-year PrEP and TasP scale-ups (2035 coverages: 47% PrEP and 88% ART) prevented 21% (17-26) and 17% (10-27) infections among FSW, respectively, and 5% (3-10) and 17% (10-27) overall. Compared with TasP scale-up alone, PrEP and TasP combined scale-up prevented 1.9× and 1.2× more infections among FSW and overall, respectively.

CONCLUSIONS

The demonstration study impact was modest, and mostly from TasP. Increasing PrEP adherence and coverage improves impact substantially among FSW, but little overall. We recommend TasP in prevention packages.

Prevalence of lung function impairment in cured pulmonary tuberculosis patients in Cotonou, Benin

SETTING

National teaching hospital for the management of respiratory diseases, Cotonou, Benin.

OBJECTIVE

1) To estimate the prevalence of lung function impairment (LFI) and associated factors in patients cured of pulmonary tuberculosis (PTB); and 2) to determine the link between human immunodeficiency virus (HIV) infection and LFI occurrence.

DESIGN

We performed a cross-sectional study in cured patients with smear-positive TB (PTB+) treated between 2012 and 2015. We recruited two control groups of 70 HIV-infected (HIV+/TB-) and 70 HIV-negative participants without TB (HIV-/TB-). We performed spirometry in all participants to identify LFI (obstructive, restrictive or mixed) and the 6-min walk test (6-MWT) in PTB+ participants. We assessed the factors associated with LFI using logistic regression.

RESULTS

Of 4711 subjects with PTB, 241 were contacted and 189 were included. The median age was 37 years; 128 (68.0%) were male. Overall, 85 cured PTB+ patients had LFI (45.0%). Extent of initial radiological lesions, time between symptom onset and treatment, and female sex were independently associated with LFI. Fifty-five (29.1%) cured PTB+ patients had an abnormal 6-MWT; those with LFI had a higher risk of poor exercise tolerance (OR 2.23; interquartile range 1.16-4.30). We did not find any association between HIV infection and LFI.

CONCLUSION

LFI is very common in cured PTB+ patients from Benin and significantly impacts exercise tolerance.

Biological Validation of Self-Reported Unprotected Sex and Comparison of Underreporting Over Two Different Recall Periods Among Female Sex Workers in Benin

Background

Self-reported unprotected sex validity is questionable and is thought to decline with longer recall periods. We used biomarkers of semen to validate self-reported unprotected sex and to compare underreporting of unprotected sex between 2 recall periods among female sex workers (FSW).

Methods

At baseline of an early antiretroviral therapy and pre-exposure prophylaxis demonstration study conducted among FSW in Cotonou, Benin, unprotected sex was assessed with retrospective questionnaires, and with vaginal detection of prostate-specific antigen (PSA) and Y-chromosomal deoxyribonucleic acid (Yc-DNA). Underreporting in the last 2 or 14 days was defined as having reported no unprotected sex in the recall period while testing positive for PSA or Yc-DNA, respectively. Log-binomial regression was used to compare underreporting over the 2 recall periods.

Results

Unprotected sex prevalence among 334 participants was 25.8% (50.3%) according to self-report in the last 2 (or 14) days, 32.0% according to PSA, and 44.3% according to Yc-DNA. The proportion of participants underreporting unprotected sex was similar when considering the last 2 (18.9%) or 14 days (21.0%; proportion ratio = 0.90; 95% confidence interval, 0.72–1.13). Among the 107 participants who tested positive for PSA, 19 (17.8%) tested negative for Yc-DNA.

Conclusions

Underreporting of unprotected sex was high among FSW but did not seem to be influenced by the recall period length. Reasons for discrepancies between PSA and Yc-DNA detection, where women tested positive for PSA but negative for Yc-DNA, should be further investigated.

Early antiretroviral therapy and daily pre-exposure prophylaxis for HIV prevention among female sex workers in Cotonou, Benin: a prospective observational demonstration study

INTRODUCTION

In sub-Saharan Africa, HIV prevalence remains high, especially among key populations. In such situations, combination prevention including clinical, behavioural, structural and biological components, as well as adequate treatment are important. We conducted a demonstration project at the Dispensaire IST, a clinic dedicated to female sex workers (FSWs) in Cotonou, on early antiretroviral therapy (E-ART, or immediate "test-and-treat") and pre-exposure prophylaxis (PrEP). We present key indicators such as uptake, retention and adherence.

METHODS

In this prospective observational study, we recruited FSWs from October 4th 2014 to December 31st 2015 and followed them until December 31st 2016. FSWs were provided with daily tenofovir disoproxil fumarate/emtricitabine (Truvada® ) for PrEP or received a first-line antiretroviral regimen as per Benin guidelines. We used generalized estimating equations to assess trends in adherence and sexual behaviour.

RESULTS

Among FSWs in the catchment area, HIV testing coverage within the study framework was 95.5% (422/442). At baseline, HIV prevalence was 26.3% (111/422). Among eligible FSWs, 95.5% (105/110) were recruited for E-ART and 88.3% (256/290) for PrEP. Overall retention at the end of the study was 59.0% (62/105) for E-ART and 47.3% (121/256) for PrEP. Mean (±SD) duration of follow-up was 13.4 (±7.9) months for E-ART and 11.8 (±7.9) months for PrEP. Self-reported adherence was over 90% among most E-ART participants. For PrEP, adherence was lower and the proportion with 100% adherence decreased over time from 78.4% to 56.7% (p-trend < 0.0001). During the 250.1 person-years of follow-up among PrEP initiators, two seroconversions occurred (incidence 0.8/100 person-years (95% confidence interval: 0.3 to 1.9/100 person-years)). The two seroconverters had stopped using PrEP for at least six months before being found HIV-infected. In both groups, there was no evidence of reduced condom use.

CONCLUSIONS

This study provides data on key indicators for the integration of E-ART and PrEP into the HIV prevention combination package already offered to FSWs in Benin. PrEP may be more useful as an individual intervention for adherent FSWs rather than a specific public health intervention. E-ART was a more successful intervention in terms of retention and adherence and is now offered to all key populations in Benin.

STUDY REGISTRATION

ClinicalTrials.gov NCT02237.

A Behavioral and Serological Survey on HIV Prevalence Among Prisoners in Benin

Cases of HIV are common in Benin, with infection rates varying according to socioeconomic and cultural factors, and by region. Certain segments of the population, such as prison inmates, sex worker clients and truck drivers are at high risk for HIV/AIDS. The aim of this study is to identify which behavioral and serological indicators contribute to the spread of HIV among prisoners. A total of 496 inmates from prisons located in all major cities in Benin were surveyed. Data was collected through interview sessions carried out using a questionnaire and through blood samples. The results show that most inmates are Beninese (83.5%), and the average age is 33 years (range: 14-80 years). No prisoner reported using a condom the last time they engaged in sexual intercourse. Blood exposure was found in 14.6% of inmates and HIV was detected in 1.4% of cases. Our analysis indicates that the length of detention and gender are factors that influence HIV status. However, age, education, nationality and HIV awareness had no significant effect on HIV prevalence among inmates. The results highlight the need to raise awareness in prisons about HIV. This can be achieved by strengthening communication strategies and by organizing HIV and sexually transmitted diseases information sessions for both prison officers and inmates.

Changes in viral hepatitis B screening practices over time in West African HIV clinics

BACKGROUND

We aimed to describe changes in hepatitis B screening practices over a 3-year period among HIV-infected patients in West Africa.

METHODS

A medical chart review was conducted in urban HIV treatment centers in Ivory Coast (3 sites), Benin, Burkina Faso, Senegal, and Togo (1 site each). Among patients who started antiretroviral treatment between 2010 and 2012, 100 per year were randomly selected from each clinic. Demographic, clinical, and laboratory data was collected using a standardized questionnaire. We assessed changes in the proportion of patients screened over time and identified predictors of screening in a multivariable logistic regression.

RESULTS

A total of 2097 patients were included (median age: 37 years, 65.4% of women). Overall, 313 (14.9%) patients had been screened for hepatitis B, with an increase from 10.6% in 2010 to 18.9% in 2012 (P<0.001) and substantial differences across countries. In multivariable analysis, being aged over 45 years (adjusted odds ratio: 1.34 [1.01-1.77]) and having an income-generating activity (adjusted odds ratio: 1.82 [1.09-3.03]) were associated with screening for hepatitis B infection. Overall, 62 HIV-infected patients (19.8%, 95% confidence interval: 15.5-24.7) were HBsAg-positive and 82.3% of them received a tenofovir-containing drug regimen.

CONCLUSION

Hepatitis B screening among HIV-infected patients was low between 2010 and 2012. The increasing availability of HBsAg rapid tests and tenofovir in first-line antiretroviral regimen should improve the rates of hepatitis B screening.

[Prevalence and factors associated with cryptococcal antigenemia in HIV-infected patients in Cotonou/Benin]

OBJECTIVE

Determine the prevalence of cryptococcal antigenemia and associated factors in HIV-infected patients in Cotonou in order to introduce systematic screening in national guidelines.

PATIENTS AND METHODS

This is a cross-sectional, descriptive and analytical study conducted from June to September 2015 in four outpatient treatment centers with adult patients infected with HIV, receiving or not antiretroviral treatment with a number of CD4≤200cell/μL and who have given their informed consent to participate in the study. For each enrolled patient, after signing the informed consent form, it was made a clinical examination and administration of a questionnaire to collect general information, treatment and biological data. Then a blood sample for counting CD4 lymphocytes and the search of cryptococcal antigenemia were done.

RESULTS

In total, 355 patients were included in the study with a mean age of 40±10.2years. The overall prevalence of cryptococcal antigenemia is 1.7%. All patient with cryptococcal antigenemia have a CD4 count below 100cells/μL with a majority having CD4 count below 50cells/μL. Body mass index<18.5kg/m², an alteration of the general condition with a CD4 lymphocyte counts<50cells/μL are the main factors associated with the occurrence of cryptococcal antigenemia.

CONCLUSION

This pilot study showed a low prevalence of cryptococcal antigenemia in the study population, but higher in highly immuno-deficient patients with CD4 counts<50cells/μl. Given the results obtained, the introduction of routine screening among patients infected with HIV could be reserved to those with CD4 counts<50cells/μl.

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.

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.

Sexual behaviour after antiretroviral therapy initiation in female sex workers and HIV-positive patients from the general population, Cotonou, Benin

From September 2008 to December 2011, we enrolled and followed-up 247 HIV-negative, 88 untreated and 32 treated HIV-positive female sex workers (FSWs), as well as 238 untreated and 115 treated HIV-positive patients from the general population (GP) of Cotonou, Benin. We wanted to assess the effect of antiretroviral therapy (ART) on sexual risk-taking in FSWs and patients from the GP. We used multivariate log binomial regression models for repeated measures to compare risky behaviours reported during pre-ART and post-ART visits and we performed linear time-trend analyses to assess changes in condom use in all five groups. At 58.8% of pre-ART and 45.3% of post-ART visits (adjusted p-value=0.293), treated FSWs have reported ≥16 clients during the last week of work. Inconsistent condom use with clients over the same period decreased by more than 50% (from 20.7 to 10.0%, adjusted p-value=0.082). In treated patients from the GP, inconsistent condom use with regular partners during the last four months was reported at 52.8% of pre-ART and 53.5% of post-ART visits (p=0.778). Reported casual sex was stable (36.8% versus 38.7%, adjusted p-value=0.924). In linear time-trend analyses, there was a significant downward trend in inconsistent condom use at the early stage of the study and stability thereafter in all HIV-negative and HIV-positive FSWs. There was no negative alteration in sexual behaviour following ART initiation either inpatients from the GP or in FSWs. The results underscore the key role of concomitant sexual risk-reduction strategies.

Naturally-occurring genetic variants in human DC-SIGN increase HIV-1 capture, cell-transfer and risk of mother-to-child transmission

BACKGROUND

Mother-to-child transmission (MTCT) is the main cause of HIV-1 infection in children worldwide. Dendritic cell-specific ICAM-3 grabbing-nonintegrin (DC-SIGN, also known as CD209) is an HIV-1 receptor that enhances its transmission to T cells and is expressed on placental macrophages.

METHODS AND FINDINGS

We have investigated the association between DC-SIGN genetic variants and risk of MTCT of HIV-1 among Zimbabwean infants and characterized the impact of the associated mutations on DC-SIGN expression and interaction with HIV-1. DC-SIGN promoter (p-336C and p-201A) and exon 4 (198Q and 242V) variants were all significantly associated with increased risk of intrauterine (IU) HIV-1 infection. Promoter variants decreased DC-SIGN expression both in vitro and in placental CD163(+) macrophages (Hofbauer cells) of HIV-1 unexposed infants but not of HIV-1 exposed infants. The exon 4 protein-modifying mutations increased HIV-1 capture and transmission to T cells in vitro.

CONCLUSION

This study provides compelling evidence to support an important role of DC-SIGN in IU HIV-1 infection.

[Mitochondrial toxicity: a case of palpebral ptosis in a woman infected by HIV and treated with HAART including zidovudine]

The usual clinical feature of mitochondrial toxicity is proximal myopathy. We present the report case of palpebral ptosis which occurred under zidovudine therapy The symptom remission was obtained by stopping the antiretroviral therapy. This involves an important vigilance from both doctor and patient.

[Undesirable effect of antiretroviral drugs in patients infected with HIV at Cotonou Benin]

OBJECTIVES

Evaluate the tolerance of highly active antiretroviral therapy (HAART) on PLWHA treated in Cotonou to improve the quality of their follow up.

METHODS

Retrospective study among PLWHA aged > or = 15 years, treated by HAART during the period February 2002 - January 2004 and who respond to one or more consultation of follow up. Adverse effects (AE) revealed by patients or noticed by the physician are analyzed.

RESULTS

The study on 130 PLWHA, revealed 62,3% receiving HAART with nonnucleoside reverse transcription inhibitor and 37,7% with protease inhibitor. 75,4% presented one or more AE. Those AE were severe for 4,6% (6 patients). The frequency of AE was significantly different by drugs used. The most common events were neurosensorial (64,6%), digestive (34,6%) and dermatologic (14,6%). 2/3 of PLWHA presented AE within the first fifteen days of treatment. The patients were compliant. Only one patient stopped voluntary the treatment.

CONCLUSION

The frequency and the type of AE occurred predispose patients to the non observance. Their follow up must therefore include education and surveillance guided by the profile of AE identified.

[Clinical and immunological profile of HIV infected patients in Cotonou, Benin]

OBJECTIVES

This study had for aim to identify the clinical status and the level of immuno-deficiency of HIV-infected patients on their first visit.

METHODS

One hundred and thirty-six HIV+ patients were prospectively evaluated from November 1, 2001 to May 31, 2002.

RESULTS

One hundred and thirty-four were infected with HIV1 and two with HIV2. The mean age on the first consultation was 37 +/- 2 years. The m/w sex ratio was 0.9. 46.3% were stage C. The main clinical symptoms were: weight loss (88%), fever (80%), cough (71%), diarrhea (51%). BMI was normal in 70% and KI > or =80% in 57% of the cases but immuno-deficiency was severe with CD4 cells count <200 per mm3 in 69%. The main diseases were digestive candidiasis (53%), pneumonia (18%), tuberculosis (12%), non-determined pneumonia (29%), prurigo (20%), zona (16%), cryptosporidiosis (4%), cerebral toxoplasmosis (3%), and Kaposi's sarcoma (1%).

[Morbidity of diabetic foot in Internal Medicine CNHU HKM, Cotonou]

The diabetes and its complications appear increasingly frequent in our medical practice. We fixed ourselves for objectives to determine the frequency of the foot diabetic in Internal Medicine at Cotonou, to count the factors etiopathogenic responsible for the lesions and to describe the clinical aspects of the lesions. We carried out a retrospective study on the 420 diabetics hospitalized of January 1, 1995 to December 31, 1999. The frequency of the foot diabetic was 16.66%, the average age of the patients 60 years and the sex ratio 2.04. The diabetes of the type 2 was most frequent (71.4%). The traumatisms were the supporting factors most often found (32.86%). The lesions were in majority (38.57%) at the stage V of the classification of Wagner. On the therapeutic level, the amputations were frequent (20%) especially the amputations of legs. The installation of medical team of education for the assumption of responsibility of the diabetes and the prevention of the complications appears essential.