Kévin Jean

Effect of Early Antiretroviral Therapy on Sexual Behaviors and HIV-1 Transmission Risk Among Adults With Diverse Heterosexual Partnership Statuses in Côte d'Ivoire

Background. The effect of early initiation of antiretroviral therapy (ART; ie, at CD4+ T-cell counts >350 cells/mm3) on sexual behaviors and human immunodeficiency virus type 1 (HIV) transmission risk has not been documented in populations other than HIV-serodiscordant couples in stable relationships. Methods. On the basis of data from a behavioral study nested in a randomized, controlled trial (Temprano-ANRS12136) of early ART, we compared proportions of risky sex (ie, unprotected sex with a partner of negative/unknown HIV status) reported 12 months after inclusion between participants randomly assigned to initiate ART immediately (hereafter, “early ART”) or according to ongoing World Health Organization criteria. Group-specific HIV transmission rates were estimated on the basis of sexual behaviors and viral load–specific per-act HIV transmission probabilities. The ratio of transmission rates was computed to estimate the protective effect of early ART. Results. Among 957 participants (baseline median CD4+ T-cell count, 478 cells/mm3), 46.0% reported sexual activity in the past month; of these 46.0%, sexual activity for 41.5% involved noncohabiting partners. The proportion of subjects who engaged in risky sex was 10.0% in the early ART group, compared with 12.8% in the standard ART group (P = .17). After accounting for sexual behaviors and viral load, we estimated that the protective effect of early ART was 90% (95% confidence interval, 81%–95%). Conclusion. Twelve months after inclusion, patients in the early and standard ART groups reported similar sexual behaviors. Early ART decreased the estimated risk of HIV transmission by 90%, suggesting a major prevention benefit among seronegative sex partners in stable or casual relationships with seropositive individuals.

Decrease in sexual risk behaviours after early initiation of antiretroviral therapy: a 24-month prospective study in Côte d'Ivoire.

Whether early antiretroviral therapy (ART) initiation could impact sexual risk behaviours remains to be documented. We aimed to investigate changes in sexual behaviours within the 24 months following an early versus standard ART initiation in HIV‐positive adults with high CD4 counts.

Level of viral suppression and the cascade of HIV care in a South African semi-urban setting in 2012.

Objective:In 2012, 7 years after the introduction of antiretroviral treatment (ART) in the South African township of Orange Farm, we measured the proportion of HIV-positive people who were virally suppressed, especially among high-risk groups (women 18–29 years and men 25–34 years). Design:A community-based cross-sectional representative survey was conducted among 3293 men and 3473 women. Methods:Study procedures included a face-to-face interview and collection of blood samples that were tested for HIV, 11 antiretroviral drugs and HIV-viral load. Results:HIV prevalence was 17.0% [95% confidence interval: 15.7–18.3%] among men and 30.1% [28.5–31.6%] among women. Overall, 59.1% [57.4–60.8%] of men and 79.5% [78.2–80.9%] of women had previously been tested for HIV. When controlling for age, circumcised men were more likely to have been tested compared with uncircumcised men (66.1 vs 53.6%; P < 0.001). Among HIV+, 21.0% [17.7–24.6%] of men and 30.5% [27.7–33.3%] of women tested positive for one or more antiretroviral drugs. Using basic calculations, we estimated that, between 2005 and 2012, ART programs prevented between 46 and 63% of AIDS-related deaths in the community. Among antiretroviral-positive, 91.9% [88.7–94.3%] had viral suppression (viral load <400 copies/ml). The proportion of viral suppression among HIV+ was 27.0% [24.3–29.9%] among women and 17.5% [14.4–20.9%] among men. These proportions were lower among the high-risk groups: 15.6% [12.1–19.7%] among women and 8.4% [5.0–13.1%] among men. Conclusion:In Orange Farm, between 2005 and 2012, ART programs were suboptimal and, among those living with HIV, the proportion with viral suppression was still low, especially among the young age groups. However, our study showed that, in reality, antiretroviral drugs are highly effective in viral suppression at an individual level.

The seasonal influence of climate and environment on yellow fever transmission across Africa

Background Yellow fever virus (YFV) is a vector-borne flavivirus endemic to Africa and Latin America. Ninety per cent of the global burden occurs in Africa where it is primarily transmitted by Aedes spp, with Aedes aegypti the main vector for urban yellow fever (YF). Mosquito life cycle and viral replication in the mosquito are heavily dependent on climate, particularly temperature and rainfall. We aimed to assess whether seasonal variations in climatic factors are associated with the seasonality of YF reports. Methodology/Principal findings We constructed a temperature suitability index for YFV transmission, capturing the temperature dependence of mosquito behaviour and viral replication within the mosquito. We then fitted a series of multilevel logistic regression models to a dataset of YF reports across Africa, considering location and seasonality of occurrence for seasonal models, against the temperature suitability index, rainfall and the Enhanced Vegetation Index (EVI) as covariates alongside further demographic indicators. Model fit was assessed by the Area Under the Curve (AUC), and models were ranked by Akaike’s Information Criterion which was used to weight model outputs to create combined model predictions. The seasonal model accurately captured both the geographic and temporal heterogeneities in YF transmission (AUC = 0.81), and did not perform significantly worse than the annual model which only captured the geographic distribution. The interaction between temperature suitability and rainfall accounted for much of the occurrence of YF, which offers a statistical explanation for the spatio-temporal variability in transmission. Conclusions/Significance The description of seasonality offers an explanation for heterogeneities in the West-East YF burden across Africa. Annual climatic variables may indicate a transmission suitability not always reflected in seasonal interactions. This finding, in conjunction with forecasted data, could highlight areas of increased transmission and provide insights into the occurrence of large outbreaks, such as those seen in Angola, the Democratic Republic of the Congo and Brazil.

A Meta-Analysis of Serological Response Associated with Yellow Fever Vaccination

Despite previous evidence of high level of efficacy, no synthetic metric of yellow fever (YF) vaccine efficacy is currently available. Based on the studies identified in a recent systematic review, we conducted a random-effects meta-analysis of the serological response associated with YF vaccination. Eleven studies conducted between 1965 and 2011 representing 4,868 individual observations were included in the meta-analysis. The pooled estimate of serological response was 97.5% (95% confidence interval [CI] = 82.9–99.7%). There was evidence of between-study heterogeneity (I2 = 89.1%), but this heterogeneity did not appear to be related to study size, study design, or seroconversion measurement or definition. Pooled estimates were significantly higher (P < 0.0001) among studies conducted in nonendemic settings (98.9%, 95% CI = 98.2–99.4%) than among those conducted in endemic settings (94.2%, 95% CI = 83.8–98.1%). These results provide background information against which to evaluate the efficacy of fractional doses of YF vaccine that may be used in outbreak situations.

Early antiretroviral therapy initiation in west Africa has no adverse social consequences: a 24-month prospective study.

Based on social indicators collected within the TEMPRANO-ANRS12136 trial, we assessed the social consequences of early antiretroviral therapy (ART) initiation in west Africa. We did not observe any significant differences in the levels or the time trends of various social indicators, including union status, HIV disclosure and HIV-related discrimination, between early and deferred ART initiation. Early ART does not carry detectable adverse social consequences that could impair its clinical and preventive benefits.

WHO guidelines for antiretroviral therapy in serodiscordant couples in sub-Saharan Africa: how many fit?

To evaluate the implication of WHO guidelines for serodiscordant couples, we interviewed HIV-infected adults on their partners serostatus. We found that 12% with more than 500 CD4+ cells/&mgr;l should be recommended antiretroviral treatment (ART) because their partner was seronegative; 24% could be recommended not to start ART because their partner was seropositive; and 64% could not be given any recommendation regarding ART early initiation because they had either no stable partnership (30%) or were in a stable partnership with a partner whose status they were not aware of (34%).