Understanding the Three Levels of HIV Epidemics According to WHO and Indonesia’s Position

MALARIA PERDHAKI-JAKARTA. The World Health Organization (WHO) and UNAIDS classify the HIV epidemic into three levels: Low-Level Epidemic, Concentrated Epidemic, and Generalized Epidemic. This classification is used to determine the extent to which the virus has spread within a particular area. Currently, Indonesia as a whole is classified as having a Concentrated Epidemic, while the Land of Papua is the only region in the country categorized as experiencing a Generalized Epidemic. This difference in classification raises questions about what each epidemic level means and how HIV spreads within communities.

A Low-Level Epidemic is the first and earliest stage of HIV transmission in a particular area. At this stage, the number of cases remains very small, and no specific population group has yet been identified as being affected by the virus. Transmission is still sporadic, isolated, and lacks a consistent pattern because the virus has only recently been introduced into the area.

The second stage is the Concentrated Epidemic. At this stage, HIV transmission has spread rapidly, but it remains largely confined to populations with high-risk behaviors. These key populations include people who inject drugs, sex workers and their clients, as well as men who have sex with men (MSM).

The greatest challenge at this stage is to prevent the barrier between high-risk populations and the general population from “collapsing.” If a member of a high-risk population has sexual intercourse with their regular partner at home, the area's epidemic status may progress to the next stage, namely a Generalized Epidemic.

The highest stage is the Generalized Epidemic, a condition in which HIV transmission is no longer confined to high-risk populations but spreads independently throughout the general population. At this stage, the barrier between these two populations has completely broken down. The virus has entered family settings and is no longer limited to prostitution networks or specific communities.

A person can become infected even if they have never visited a red-light district or used illicit drugs. Housewives may acquire HIV from their husbands, while infants can become infected from their mothers during pregnancy or through breastfeeding. Meanwhile, HIV can spread among the general population through heterosexual sexual transmission.

WHO and UNAIDS define a Generalized Epidemic based on measurable epidemiological indicators, specifically when HIV prevalence among pregnant women attending antenatal care is consistently above 1%. Pregnant women are used as the benchmark because they represent the general population without high-risk behaviors.

In the Land of Papua, this prevalence has reached approximately 2.3%, well above the threshold. Because of its Generalized Epidemic status, the Land of Papua now receives a comprehensive, population-wide, and systematic response, with strengthened primary healthcare services through community health centers (Puskesmas) serving as the frontline of the intervention.