Infection par le virus Nipah

Nipah virus infection is a zoonotic viral disease caused by a paramyxovirus of the genus Henipavirus, naturally hosted by fruit bats of the Pteropodidae family ^[1][3][4]. It is transmitted to humans from animals, through contaminated food, or directly between people, and is classified as a Biosafety Level-4 agent endemic in South Asia ^[1][4][5].

Infection produces a range from asymptomatic cases to acute respiratory illness and encephalitis in the most severe presentations ^[2]. Most patients develop fever with neurological symptoms such as headache or confusion and respiratory symptoms such as cough or breathing difficulty, alongside chills, fatigue, vomiting, and diarrhoea ^[2]. The incubation period is typically 3 to 14 days, rarely up to 45 days, and severe disease with brain swelling and frequent death is especially associated with neurological involvement ^[2].

Outbreaks were first detected in 1998–1999 among pig-associated settings in Malaysia and Singapore, with no further reports from those countries since ^[1][2]. From 2001 onward, annual or periodic outbreaks have occurred in Bangladesh and India, and a 2014 event was reported in the Philippines ^[1][2]. The virus shows sporadic outbreak patterns, high case fatality of roughly 40%–80%, and is considered endemic in South Asia with pandemic potential ^[3][4][5].

The natural reservoir is fruit bats of the Pteropodidae family, with transmission to humans via direct contact with infected bats, pigs, or horses and via consumption of bat-contaminated fruit products such as raw date palm juice ^[1][2]. Human-to-human spread occurs through close contact, including in healthcare settings and among family caregivers, with increased risk in overcrowded or poorly ventilated facilities ^[1][2]. Contaminated food and direct interpersonal exposure are additional routes ^[1][2].

Public-health prevention emphasizes strengthening surveillance, laboratory services, infection prevention and control in healthcare, and community engagement supported by WHO and partners ^[1]. A One Health approach addressing bat-to-human chains is considered necessary, and rapid diagnosis with implementation of infection control measures is essential to contain outbreaks ^[5]. No approved vaccines or antivirals are available, so preparedness depends on technical guidance, training, and cross-country exchange of expertise ^[1][3][5].

1. 1 World Health Organization. Nipah virus fact sheet [Internet]. cited 4 Sept 2026. Available from: https://www.who.int/news-room/fact-sheets/detail/nipah-virus
2. 2 World Health Organization. Nipah virus infection [Internet]. cited 4 Sept 2026. Available from: https://www.who.int/health-topics/nipah-virus-infection
3. 3 Madhukalya R et al. Nipah virus: pathogenesis, genome, diagnosis, and treatment. Appl Microbiol Biotechnol. 2025 Jul 1. PMID: 40593310. doi: 10.1007/s00253-025-13474-6. PubMed: https://pubmed.ncbi.nlm.nih.gov/40593310/
4. 4 Angeletti S et al. Molecular epidemiology and phylogeny of Nipah virus infection: A mini review. Asian Pac J Trop Med. 2016 Jul. PMID: 27393089. doi: 10.1016/j.apjtm.2016.05.012. PubMed: https://pubmed.ncbi.nlm.nih.gov/27393089/
5. 5 Aditi et al. Nipah virus infection: A review. Epidemiol Infect. 2019 Jan. PMID: 30869046. doi: 10.1017/S0950268819000086. PubMed: https://pubmed.ncbi.nlm.nih.gov/30869046/