Understanding the joint effect of the behavioural and biological risk reduction factors on HIV

The conventional approach in determining HIV risk factors fails to consider the influence behavioural and biological factors may have when modelled jointly. This study investigates the extent of influence behavioural and biological factors jointly have on HIV prevalence. The approach adapted in the modelling includes assessment of multicollinearity among the variables, principal component regression analysis to deal with multicollinearity problem, checking for the presence of confounding factors and significant interaction effects. In determining the joint effect, logistic regression model was fitted to the HIV data obtained from the Zimbabwe Demographic and Health Survey of 2011 (ZDHS, 2010). Besides age, marital status, total number of lifetime sex partners and condom use being significant for both gender, genital discharge and paid for sex for males and place of residence, age at sexual debut, genital sore, relationship with recent partner, educational attainment and STI for females were significant. Significant interaction terms between biological and behavioural factors were revealed and thus demonstrated the importance of being cautious when interpreting the results of joint modelling. Generalised Variance Inflation Factors (GVIF) detected multicollinearity for some variables in both models and Principal Component analysis obtained four factors (sexual relation, residential status, STI status and sexual partnership) for females and three (STI occurrence, sexual relationship and residential status) for males thus addressing the problem. Significant interaction between behavioural and biological factors were noted. The findings suggest meticulous consideration in assessing interrelationships among independent variables and give an appreciation and understanding of how statistical methods can be applied in the public health sector.StatisticsM. Sc. (Statistics

Safety and efficacy of the PrePex device in HIV-positive men: A single-arm study in Zimbabwe

<div><p>Male circumcision (MC) for sexually active, HIV-negative men reduces HIV transmission and averts HIV infections. Excluding HIV-positive men from MC decreases access to additional health and hygiene benefits. In settings where HIV-testing is, or is perceived to be, required for MC, testing may reduce MC uptake. Reducing promotion of HIV testing within MC settings and promoting device-based MC may speed MC scale-up. To assess safety and efficacy of PrePex MC device among HIV-positive men, we conducted a one-arm, open-label, prospective study in otherwise healthy HIV-positive men in Zimbabwe.</p><p>Methods</p><p>We aimed to determine if the adverse event (AE) rate was non-inferior to an AE rate of 2%, a rate considered the global standard of MC safety. Study procedures, AE definitions, and study staff were unchanged from previous PrePex Zimbabwe trials. After PrePex placement and removal, weekly visits assessed wound healing. Men returned on Day 90. Safety was defined as occurrence of moderate and serious clinical AEs. Efficacy was defined as ability to reach the endpoint of complete circumcision.</p><p>Results</p><p>Among 400 healthy, HIV-positive, consenting adults, median age was 40 years (IQR: 34, 46); 79.5% in WHO stage 2; median CD4 was 336.5c/μl (IQR: 232, 459); 337 (85%) on anti-retroviral therapy. Among 385 (96%) observed completely healed, median days to complete healing was 42 (IQR: 35–49). There was no association between time to healing and CD4 (p = 0.66). Four study-related severe AEs and no moderate AEs were reported: severe/moderate AE rate of 1.0% (95% CI: 0.27% to 2.5). This was non-inferior to 2% AEs (p = 0.0003). All AEs were device displacements resulting in surgical MC and, subsequently, complete healing.</p><p>Conclusion</p><p>Male circumcision among healthy, HIV-positive men using PrePex is safe and effective. Reducing the barrier of HIV testing while improving counseling for safer sex practices among all MC clients could increase MC uptake and avert more HIV infections.</p></div

Participant demographics (N = 400).

<p>Participant demographics (N = 400).</p

Summary of AEs reported in previous PrePex studies in Zimbabwe.

<p>Summary of AEs reported in previous PrePex studies in Zimbabwe.</p

Percent of men healed at each visit, by CD4 (N = 385).

<p>Percent of men healed at each visit, by CD4 (N = 385).</p