Twenty-five years of Nipah outbreaks in Southeast Asia: A persistent threat to global health

Objectives: Nipah virus (NiV), a bat-borne zoonotic pathogen, poses persistent threats to global public health due to severe clinical manifestation and high case fatality rate (CFR). A critical examination of NiV outbreaks is essential for refining strategies and mitigating the impact of future infections. In this study, we provide a concise update on global NiV outbreaks that occurred during the past 25 years. Methods: In this geospatial study, we conducted an in-depth examination of the epidemiological characteristics of human NiV cases and deaths from 1998 to 2024 through multiple analyses of public data and official reports. Results: NiV emerged in 1998 in Malaysia during an outbreak among pig farmers. Since then, NiV outbreaks have been documented in five countries of South and Southeast Asia (Bangladesh, India, Malaysia, Philippines, and Singapore). As of May 2024, there have been 754 confirmed human NiV cases with 435 deaths (CFR: 58%) reported in these five countries. Bangladesh records the highest incidence (341 cases and 241 deaths; CFR: 71%) followed by Malaysia (283 cases and 109 deaths; CFR: 39%), India (102 cases and 74 deaths; CFR: 73%), the Philippines (17 cases and nine deaths; CFR: 53%), and Singapore (11 cases and one death; CFR: 9%). Conclusions: The clinical outcomes of NiV have been underscoring constant global public health threats as no effective therapies and vaccines are available. Strong global understandings, with an eye on developing vaccines and therapeutics, are required to minimize clinical outcomes and future threats of NiV.