The emergence of Nipah virus illustrates how wildlife, livestock and environmental change intersect to create pandemic risk. Understanding its reservoirs, transmission pathways and the broader ecological context is essential for UPSC aspirants tackling GS‑2 (Polity), GS‑3 (Economy & Environment) and GS‑4 (Ethics) questions. Key Developments 1998‑1999 outbreak in Malaysia linked to amplifying host pigs; culling of ~1.1 million pigs curbed spread. Subsequent outbreaks in Bangladesh and India occurred without pigs, driven by consumption of contaminated date‑palm sap and direct bat‑to‑human transmission. Deforestation in the Amazon and Southeast Asia, and permafrost thaw, are expanding human‑wildlife interfaces, raising the probability of new zoonotic spillover events. Important Facts • Primary reservoirs are Pteropus bats, with seroprevalence 23‑65 %. • The virus possesses a single‑stranded negative‑sense RNA virus genome of ~18 kb, near the upper size limit for paramyxoviruses. • Mutation rate enables quick adaptation but also risks error catastrophe; mutagenic antivirals like ribavirin exploit this vulnerability. • Human activities that increase contact – intensive livestock farming, wildlife trade, and encroachment into bat habitats – are central to spillover dynamics. UPSC Relevance Understanding Nipah’s ecology helps answer GS‑2 questions on public‑health policy, GS‑3 queries on environmental degradation and disease emergence, and GS‑4 debates on balancing biodiversity conservation with disease control. The case underscores the need for a One‑Health approach, integrating human, animal and ecosystem health. Way Forward Strengthen surveillance of bat populations and high‑risk interfaces (e.g., date‑palm sap collection sites). Promote habitat preservation and regulated wildlife trade to reduce forced contact. Adopt One‑Health frameworks for coordinated response across health, agriculture and forest departments. Research mutagenic antivirals and vaccine candidates targeting the conserved proteins of Nipah virus . By linking ecological change to disease risk, aspirants can craft nuanced answers that integrate science, policy and ethics – a skill crucial for the UPSC mains.