Among key populations in India, the most common route of HIV transmission in the Northeast region is:

Explanation

## HIV Transmission in Northeast India: Regional Epidemiology **Key Point:** Intravenous drug use (PWID — People Who Inject Drugs) is the predominant mode of HIV transmission in the Northeast region of India, particularly in states like Manipur, Mizoram, and Nagaland. ### Geographic Variation in HIV Epidemiology India's HIV epidemic is **not uniform** across regions. The Northeast has a distinct epidemiological profile: | Region | Dominant Transmission Route | Key Characteristics | | --- | --- | --- | | **Northeast India** (Manipur, Mizoram, Nagaland, Assam) | PWID (IV drug use) | ~50–60% of infections; heroin trafficking routes; shared injection equipment | | **South India** (Karnataka, Tamil Nadu, Andhra Pradesh) | Sex work, heterosexual contact | Concentrated in FSW and MSM networks; spillover to general population | | **West India** (Maharashtra, Gujarat) | Heterosexual, MSM, PWID (mixed) | Urban centers; mixed epidemic | | **All-India General Population** | Heterosexual contact | 87–88% of total infections | **High-Yield:** The Northeast is the **PWID-driven epidemic hotspot** in India. This is a high-yield fact for regional epidemiology questions. ### Why PWID Dominates in Northeast? 1. **Geographic proximity** to the Golden Triangle (opium production region) 2. **High heroin availability** and low cost 3. **Unsafe injection practices** — sharing of needles and syringes 4. **Limited harm reduction services** historically (though improving) 5. **Young age of initiation** — often <25 years ### Clinical Pearl Northeast India has the **highest HIV prevalence among PWID** globally — up to 30–40% in some districts (Manipur). This has led to: - Needle and syringe exchange programs (NSEP) - Opioid substitution therapy (OST) expansion - Targeted testing and treatment in PWID networks **Mnemonic:** **NEID** = **N**ortheast = **E**PWID (Intravenous Drug use) = **I**ncidence hotspot = **D**rug trafficking routes. **Warning:** Do not assume the Northeast has the same epidemiology as all-India. A question specifically asking about the Northeast is testing knowledge of regional variation — PWID is the answer.