Phylogenetic Relatedness of Circulating HIV-1C Variants in Mochudi, Botswana

Background: Determining patterns of HIV transmission is increasingly important for the most efficient use of modern prevention interventions. HIV phylogeny can provide a better understanding of the mechanisms underlying HIV transmission networks in communities. Methods: To reconstruct the structure and dynamics of a local HIV/AIDS epidemic, the phylogenetic relatedness of HIV-1 subtype C env sequences obtained from 785 HIV-infected community residents in the northeastern sector of Mochudi, Botswana, during 2010–2013 was estimated. The genotyping coverage was estimated at 44%. Clusters were defined based on relatedness of HIV-1C env sequences and bootstrap support of splits. Results: The overall proportion of clustered HIV-1C env sequences was 19.1% (95% CI 17.5% to 20.8%). The proportion of clustered sequences from Mochudi was significantly higher than the proportion of non-Mochudi sequences that clustered, 27.0% vs. 14.7% (p = 5.8E-12; Fisher exact test). The majority of clustered Mochudi sequences (90.1%; 95% CI 85.1% to 93.6%) were found in the Mochudi-unique clusters. None of the sequences from Mochudi clustered with any of the 1,244 non-Botswana HIV-1C sequences. At least 83 distinct HIV-1C variants, or chains of HIV transmission, in Mochudi were enumerated, and their sequence signatures were reconstructed. Seven of 20 genotyped seroconverters were found in 7 distinct clusters. Conclusions: The study provides essential characteristics of the HIV transmission network in a community in Botswana, suggests the importance of high sampling coverage, and highlights the need for broad HIV genotyping to determine the spread of community-unique and community-mixed viral variants circulating in local epidemics. The proposed methodology of cluster analysis enumerates circulating HIV variants and can work well for surveillance of HIV transmission networks. HIV genotyping at the community level can help to optimize and balance HIV prevention strategies in trials and combined intervention packages

Phylodynamic analysis of HIV sub-epidemics in Mochudi, Botswana

Southern Africa continues to be the epicenter of the HIV/AIDS epidemic. This HIV-1 subtype C epidemic has a predominantly heterosexual mode of virus transmission and high (>15%) HIV prevalence among adults. The epidemiological dynamics of the HIV-1C epidemic in southern Africa are still poorly understood. Here, we aim at a better understanding of HIV transmission dynamics by analyzing HIV-1 subtype C sequences from Mochudi, a peri-urban village in Botswana. HIV-1C env gene sequences (gp120 V1C5) were obtained through enhanced household-based HIV testing and counseling in Mochudi. More than 1200 sequences were generated and phylogenetically distinct sub-epidemics within Mochudi identified. The Bayesian birth-death skyline plot was used to estimate the effective reproductive number, R, and the timing of virus transmission, to classify sub-epidemics as “acute” (those with recent viral transmissions) or “historic” (those without recent viral transmissions). We identified two of the 15 sub-epidemics as “acute.” The median estimates of R among the clusters ranged from 0.72 to 1.77. The majority of HIV lineages, 11 out of 15 clusters with 5+ members, appear to have been introduced to Mochudi between 1996 and 2002. The median peak duration of viral transmissions was 7.1 years (range 2.9–9.7 years). The median life span of identified HIV sub-epidemics, i.e., the time between the inferred epidemic origin and its most recent sample, was 13.1 years (range 10.2–22.1 years). Most viral transmissions within the sub-epidemics occurred between 1997 and 2007. The time period during which infected people are infectious appears to have decreased since the introduction of the national ART program in Botswana. Real-time HIV genotyping and breaking down local HIV epidemics into phylogenetically distinct sub-epidemics may help to reveal the structure and dynamics of HIV transmission networks in communities, and aid in the design of targeted interventions for members of the acute sub-epidemics that likely fuel local HIV/AIDS epidemics

Phylodynamic analysis of HIV sub-epidemics in Mochudi, Botswana

Southern Africa continues to be the epicenter of the HIV/AIDS epidemic. This HIV-1 subtype C epidemic has a predominantly heterosexual mode of virus transmission and high (>15%) HIV prevalence among adults. The epidemiological dynamics of the HIV-1C epidemic in southern Africa are still poorly understood. Here, we aim at a better understanding of HIV transmission dynamics by analyzing HIV-1 subtype C sequences from Mochudi, a peri-urban village in Botswana. HIV-1C env gene sequences (gp120 V1C5) were obtained through enhanced household-based HIV testing and counseling in Mochudi. More than 1200 sequences were generated and phylogenetically distinct sub-epidemics within Mochudi identified. The Bayesian birth-death skyline plot was used to estimate the effective reproductive number, R, and the timing of virus transmission, to classify sub-epidemics as "acute" (those with recent viral transmissions) or "historic" (those without recent viral transmissions). We identified two of the 15 sub-epidemics as "acute." The median estimates of R among the clusters ranged from 0.72 to 1.77. The majority of HIV lineages, 11 out of 15 clusters with 5+ members, appear to have been introduced to Mochudi between 1996 and 2002. The median peak duration of viral transmissions was 7.1 years (range 2.9-9.7 years). The median life span of identified HIV sub-epidemics, i.e., the time between the inferred epidemic origin and its most recent sample, was 13.1 years (range 10.2-22.1 years). Most viral transmissions within the sub-epidemics occurred between 1997 and 2007. The time period during which infected people are infectious appears to have decreased since the introduction of the national ART program in Botswana. Real-time HIV genotyping and breaking down local HIV epidemics into phylogenetically distinct sub-epidemics may help to reveal the structure and dynamics of HIV transmission networks in communities, and aid in the design of targeted interventions for members of the acute sub-epidemics that likely fuel local HIV/AIDS epidemics

Feasibility and acceptability of peer-delivered interventions using mHealth for PrEP services among adolescent girls and young women in DREAMS program in Botswana

Background Adolescent girls and young women accounted for 25% of all new HIV infections despite representing only 10% of the population in Sub Saharan Africa. PEPFAR has launched the Determined, Resilient, Empowered, AIDS-free, Mentored, and Safe (DREAMS) initiative, a comprehensive HIV prevention program including PrEP services. Among adolescent girls and young women, PrEP adherence is currently sub-optimal. Tailored strategies for adolescent girls and young women to improve access and use of PrEP delivery are urgently needed to maximise its potential. Recommended interventions include peer-delivered interventions using mobile technology. However, data on the feasibility and acceptability of this approach is limited for SSA. Objectives We assessed the feasibility and perceived acceptability of providing mHealth peer-delivered interventions to support PrEP services among adolescent girls and young women in Botswana. Methods This cross-sectional study included HIV-negative women aged 18–24 years old seeking health services at DREAMS-supported facilities. Participants completed a survey assessing the feasibility and perceived acceptability of the mHealth peer-delivered interventions, which included the Acceptability of Intervention Measure (AIM). Descriptive analyses were performed. Results A total of 131 participated in the study. Overall, 89% owned a mobile phone (feasibility). There was no difference in cell phone ownership between participants from rural and urban settings. Among participants, 85% reported interest in participating in a mHealth peer-delivered intervention if it was available to them. Regarding perceived acceptability for mHealthpeer support groups for PrEP, the average score on the AIM was 3.8 out of 5 (SD = 0.8). Conclusion mHealthpeer-delivered interventions appear to be feasible and perceived acceptable among adolescent girls and young women in Botswana. This modality should be incorporated into PEPFAR’s programmatic toolkit of implementation strategies to improve PrEP services

Estimated age and gender profile of individuals missed by a home-based HIV testing and counselling campaign in a Botswana community

Introduction: It would be useful to understand which populations are not reached by home-based HIV-1 testing and counselling (HTC) to improve strategies aimed at linking these individuals to care and reducing rates of onward HIV transmission. Methods: We present the results of a baseline home-based HTC (HBHTC) campaign aimed at counselling and testing residents aged 16 to 64 for HIV in the north-eastern sector of Mochudi, a community in Botswana with about 44,000 inhabitants. Collected data were compared with population references for Botswana, the United Nations (UN) estimates based on the National Census data and the Botswana AIDS Impact Survey IV (BAIS-IV). Analyzed data and references were stratified by age and gender. Results: A total of 6238 age-eligible residents were tested for HIV-1; 1247 (20.0%; 95% CI 19.0 to 21.0%) were found to be HIV positive (23.7% of women vs. 13.4% of men). HIV-1 prevalence peaked at 44% in 35- to 39-year-old women and 32% in 40- to 44-year-old men. A lower HIV prevalence rate, 10.9% (95% CI 9.5 to 12.5%), was found among individuals tested for the first time. A significant gender gap was evident in all analyzed subsets. The existing HIV transmission network was analyzed by combining phylogenetic mapping and household structure. Between 62.4 and 71.8% of all HIV-positive individuals had detectable virus. When compared with the UN and BAIS-IV estimates, the proportion of men missed by the testing campaign (48.5%; 95% CI 47.0 to 50.0%) was significantly higher than the proportion of missed women (14.2%; 95% CI 13.2 to 15.3%; p<0.0001). The estimated proportion of missed men peaked at about 60% in the age group 30 to 39 years old. The proportions of missed women were substantially smaller, at approximately 28% within the age groups 30 to 34 and 45 to 49 years old. Conclusions: The HBHTC campaign seems to be an efficient tool for reaching individuals who have never been tested previously in southern African communities. However, about half of men from 16 to 64 years old were not reached by the HBHTC, including about 60% of men between 30 and 40 years old. Alternative HTC strategies should be developed to bring these men to care, which will contribute to reduction of HIV incidence in communities

Phylogenetic relatedness of HIV-1C <i>env</i> sequences based on the ML_FastTree2 + ML_PhyML analysis.

<p>The identified clusters with bootstrap support of ≥80% are collapsed. The collapsed clusters shown in red represent Mochudi-unique clusters; in blue, Mochudi mixed clusters with other Botswana sequences; in orange, non-Mochudi clusters with Botswana sequences; and in green, non-Botswana clusters. Clusters with mother-infant pairs from two MTCT studies in Malawi are shown by asterisks <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0080589#pone.0080589-Russell1" target="_blank">[78]</a> and green circle <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0080589#pone.0080589-Kumar1" target="_blank">[79]</a>.</p

Selected countries representation of HIV-1C <i>env</i> sequences included in analysis.

<p>Selected countries representation of HIV-1C <i>env</i> sequences included in analysis.</p

The HIV-1C <i>env</i> gp120 V1–C5 signature sequences across 22 clusters with 3+ members, VESPA analysis.

<p>The HIV-1C <i>env</i> gp120 V1–C5 signature sequences across 22 clusters with 3+ members, VESPA analysis.</p

CD4 levels in the prospective cohort of individuals with primary HIV-1C infection in Botswana and seroconveters in this study.

<p> post-seroconversion, p/s.</p