Concentrated HIV subepidemics in generalized epidemic settings

Area of Science:

• Epidemiology
• Public Health
• Infectious Diseases

Background:

• Generalized HIV epidemics often mask concentrated epidemics within specific high-risk populations.
• Geographical heterogeneity in HIV prevalence is significant, even within generalized epidemic settings.
• Targeted interventions within 'high-transmission zones' remain an under-explored strategy.

Purpose of the Study:

• To review recent studies on concentrated HIV epidemics within generalized settings.
• To examine the role of targeted interventions in high-prevalence countries.
• To assess findings related to geographical heterogeneity and high-risk groups.

Main Methods:

• Review of recent studies focusing on high-risk populations (MSM, PWID, sex workers).
• Analysis of geographical heterogeneity in HIV prevalence in 10 countries with the highest HIV prevalence.
• Inclusion of findings from phylogenetic studies and mathematical models.

Main Results:

• Men who have sex with men (MSM) consistently show higher HIV prevalence than the general population.
• Limited and often outdated prevalence data exists for people who inject drugs (PWID) in sub-Saharan Africa.
• Recent studies identified high HIV prevalence in geographically concentrated areas (e.g., slums, peri-urban, fishing villages) in Kenya, South Africa, and Uganda.

Conclusions:

• Empirical findings, phylogenetic evidence, and mathematical models support targeted HIV prevention.
• There is a clear rationale for testing the feasibility, acceptability, and effectiveness of targeted interventions.
• Such targeted approaches are recommended to supplement general population HIV prevention measures in hyperendemic settings.