In India, the most common route of HIV transmission accounts for approximately 87% of all new infections. Which of the following is the most common mode of transmission in the Indian HIV epidemic?

Explanation

## HIV Transmission Routes in India **Key Point:** Heterosexual transmission is the dominant mode of HIV acquisition in India, accounting for 87–90% of all new infections as per NACO (National AIDS Control Organization) surveillance data. ### Epidemiological Context Unlike Western countries where men who have sex with men (MSM) and people who inject drugs (PWID) form the primary transmission clusters, India's HIV epidemic is predominantly driven by heterosexual contact. This reflects: 1. **Population dynamics** — India has a large general population with high rates of unprotected sexual contact, particularly in high-risk groups (female sex workers, clients of sex workers, and their partners). 2. **Sex worker networks** — Female sex workers (FSWs) and their clients serve as a bridge population, facilitating transmission into the general heterosexual population. 3. **Gender disparity** — Women account for ~39% of people living with HIV (PLHIV) in India, predominantly through heterosexual transmission from infected partners. ### Comparative Frequency of Other Routes | Route | Frequency in India | Notes | |-------|-------------------|-------| | **Heterosexual contact** | 87–90% | Dominant; includes FSW networks | | **Mother-to-child transmission (MTCT)** | 5–7% | Declining with PMTCT programs | | **Intravenous drug use** | 2–3% | Concentrated in Northeast states (Manipur, Nagaland) | | **Blood transfusion** | <1% | Rare; improved blood screening | | **Occupational exposure (healthcare)** | <0.1% | Very rare with universal precautions | **High-Yield:** NACO classifies India's HIV epidemic as "concentrated" in key populations (FSWs, clients, MSM, PWID) but with significant spillover into the general heterosexual population — making heterosexual contact the single largest transmission route. **Clinical Pearl:** When counseling an HIV-positive patient in India, heterosexual transmission should be the first assumption unless the patient explicitly reports other risk factors (IVDU, MSM behavior, or occupational exposure). [cite:Park 26e Ch 5]