For many countries, in particular in sub-Saharan Africa, Demographic and Health Surveys (DHS) are the main estimates of HIV prevalence at national levels in general population. Several DHS collect longitude and latitude of surveyed clusters.In this paper, we present three methodological approaches for mapping spatial variations of HIV prevalence from DHS. These approaches are applied to DHS simulation sampled from a model country. The estimated surfaces are then compared with the initial surface of the model.We show that a method using kernel estimators with adaptive bandwidths of the same number of observed people allows estimating main regional trends of the epidemics. Its application to data from 2003 DHS of Burkina Faso give a plausible picture of the epidemiological situation in this country.Keywords: interpolation, regional trends, methodology, demographic and health surveys, developing countries, HIV

In Vietnam, harm reduction programs to control HIV among people who inject drugs (PWID) were implemented approximately 10 years ago. Since then, the HIV prevalence has declined in this population, however, the impact of these programs on the rate of new HIV and Hepatitis C (HCV) infections remains unknown as high mortality can exceed the rate of new infections. We evaluated HIV and HCV incidences in a cohort of active PWID in HaiPhong in 2014, who were recruited from a community-based respondent driven sampling (RDS) survey and followed for 1 year. Only HIV-negative or HCV-negative participants not on medication assisted treatment (MAT) were eligible. HIV/HCV serology was tested at enrollment and at 32- and 64-week follow-up visits. Among 603 RDS participants, 250 were enrolled in the cohort, including 199 HIV seronegative and 99 HCV seronegative PWID. No HIV seroconversion was reported during the 206 person-years (PY) of follow-up (HIV incidence of 0/100PY, one-sided 97.5%CI:0-1.8/100 PY). Eighteen HCV seroconversions were reported for an incidence of 19.4/100 PY (95%CI;11.5-30.7). In multivariate analysis, “Injecting more than twice daily” was associated with HCV seroconversion with an adjusted odds ratio of 5.8 (95%CI;1.8–18.1). In Hai Phong, in a context that demonstrates the effectiveness of HIV control programs, the HCV incidence remains high. New strategies such as mass access to HCV treatment should be evaluated in order to tackle HCV transmission among PWID.

Objective: We assessed the association between methamphetamine use and lack of viral suppression among a cohort of HIV-seropositive persons who inject drugs (PWID) in Hai Phong, Vietnam. Design: Cohort study with random effects logit modeling and mediation analysis for antiretroviral therapy (ART) adherence. Methods: PWID were recruited from October 2016 to October 2017; HIV-seropositive PWID were enrolled in a cohort to assess HIV viral loads, changes in drug use, risk behaviors, and ART adherence during 24-month follow-up. Methamphetamine use in last 30 days was divided into three categories: 0 days (no use), 1–19 days (intermediate), and 20 or more days (heavy). Bivariate and a multivariable random effects logit models were used to assess the relationship between methamphetamine use and not being virally suppressed. We also assessed self-reported ART adherence as a mediating factor. Results: A total of 645 HIV-seropositive PWID were included at baseline; 95% male, average age 40 (SD = 6.4). At baseline, methamphetamine use in last 30 days was 64% no use, 32% intermediate use, 4% heavy use. Approximately 74% of PWID reported high/complete adherence; 76% were at viral suppression. In random effects analysis, recent methamphetamine use was associated with not being virally suppressed during follow-up (adjusted odds ratio: 1.84, 95% confidence interval: 1.06, 3.17); the effect was not explained by a mediating effect of self-reported adherence to ART. Conclusion: Recent methamphetamine use is associated with not being virally suppressed among PWID. The results of this study indicate the need for targeted interventions for methamphetamine use with special focus on those with HIV infection.

HIV-1 transmission rates have been reduced over the last decade, an estimated 2 million new infections per year arise, including 220,000 paediatric cases. The main post-natal HIV exposure is through breastfeeding, where both its duration and modality (exclusive or not) are associated with postnatal transmission. The ANRS 12174 trial compared HIV-1 postnatal transmission of 2 prophylaxis drugs for infants during lactation (lamivudine and lopinavir-ritonavir). Our objective has been to examine the feeding practices and the determinants of exclusive/ predominant (EPBF) or any breastfeeding among the participants of this trial in Burkina Faso, South Africa, Uganda and Zambia. Mothers infected with HIV-1 and their uninfected offspring were followed from day 7 after birth for 50 weeks, keeping monthly records of their feeding patterns. Feeding was classified into 3 categories: 1) exclusive breastfeeding during the first six months, only breast-milk being given to infant for 6 months, 2) predominant breastfeeding, breast-milk with liquid-based items being given, and 3) mixed feeding, other non-breast milk or solid food being given in addition to breast milk with or without liquid-based items. The categories were merged into 2 groups: EPBF applying to infants aged <6 months and mixed feeding applying to infants of any age. The feeding patterns have been given as Kaplan-Meier curves. A flexible parametric multiple regression model was used to identify the determinants of the mothers’ feeding behaviour. A total of 1,225 mother-infant pairs provided feeding data from Burkina Faso (N = 204), South Africa (N = 213), Uganda (N = 274) and Zambia (N = 534) between November 2009 and March 2013. The mean maternal age was 27.4 years and the mean BMI was 24.5. 57.7 and 93.9% of mothers initiated breastfeeding within the first hour and first day, respectively. Overall, the median durations of any form of breastfeeding and EPBF were 40.6, and 20.9 weeks, respectively. Babies randomized to the lopinavir/ritonavir group in South Africa tended to do less EPBF than those in the lamivudine group. Overall the group of mothers aged between 25 and 30 years, those married, employed or multiparous tended to stop early EPBF. Mothers living in Uganda or Zambia, those aged between 25 -30 years, better educated (at least secondary school level), employed or having undergone C-section stopped any breastfeeding early. There is a need to improve breastfeeding and complementary feeding practices of children, particularly those exposed to HIV and anti-retrovirals, taking into account context and socio-demographic factors. Clinical trial registration: NCT00640263 .

People who inject drugs (PWID) are a dominant risk group afflicted by blood‐borne viruses, mental health disorders, and social precariousness. Risk reduction interventions are administered to PWID regardless of their characteristics or specific risks. The objective of this cross‐sectional analysis was to empirically identify profiles of PWID regarding their drug use, risk behaviors, and mental health in order to tailor adapted interventions taking into account limited access to comprehensive care in middle‐income countries. PWID were recruited using respondent‐driven sampling. PWID with urine testing positive for heroin or methamphetamine and manifesting recent skin injection marks were enrolled. Classification of participants was based on drug use, injection, risky sexual behavior, and mental health data. This was subjected to multiple correspondence analysis followed by hierarchical cluster analysis combined with K‐means methodology. From October 2016 to January 2017, 1490 participants were recruited of which 1383 were eligible and enrolled. HCV prevalence was 70.5% and HIV prevalence 29.4%. The cluster analysis identified five distinct profiles: profile 1: recent injection practices and high alcohol consumption, profile 2: at‐risk injection and sexual behaviors with precarious situations, profile 3: no sexual activity and older age, profile 4: frequent injections with high methamphetamine use, and profile 5: stable partnerships and less frequent injections. Our study has identified profiles of PWID at particularly high risks, and they should thus be targeted for interventions tailored to their specific risks.

Aims: To describe the use of large-scale respondent driven sampling (RDS) surveys to demonstrate the “end of an HIV epidemic” (HIV incidence < 0.5/100 person-years) among persons who inject drugs (PWID) in a middle-income country. Large sample sizes are needed to convincingly demonstrate very low incidence rates.Methods: 4 large surveys (Ns approximately 1500 each) were conducted among PWID in Hai Phong, Vietnam in 2016–2019. Respondent driven sampling (RDS) with a modification to add snowball sampling was used for recruiting participants. HIV incidence was measured through recency testing, repeat participants across multiple surveys and in a cohort study of PWID recruited from the surveys. RDS analytics (time to equilibria and homophilies for major variables) were used to assess similarities/differences in RDS only versus RDS plus snowball recruiting. Characteristics were compared among respondents recruited through standard RDS recruitment versus through snowball sampling. An overall assessment of the robustness of RDS to modification was made when adding a snowball sampling recruitment.Results: RDS recruiting was very efficient in the first 5 weeks of each survey with approximately 180 respondents recruited per week. Recruiting then slowed considerably, and snowball sampling (permitting an individual respondent to recruit large numbers of new respondents) was added to the existing RDS recruiting. This led to recruiting within 13–14 weeks of 1383, 1451, 1444 and 1268 respondents, close to the target of 1500 respondents/survey.Comparisons of participants recruited through standard RDS method and respondents recruited through snowball methods showed very few significant differences. RDS analytics (quickly reaching equilibria, low homophilies) were favorable for both RDS recruited and total numbers of participants in each survey. DRug use and Infections in ViEtnam (DRIVE) methods have now been officially adopted in other provinces.Conclusions: RDS appears to be quite robust with respect to adding a modest number of participants recruited through snowball sampling. Large sample sizes can provide compelling evidence for “ending an HIV epidemic” to policy makers in a PWID population in a middle income country setting.