Causative Agent
Nipah virus, Paramyxoviridae family.
Incubation Period
4-45 days
Infectious Period
Possible human-to-human transmission reported in Bangladesh.
Transmission
Via direct contact with secretions, tissues or respiratory droplets of sick pigs. Ingestion of raw fruits contaminated with urine or saliva of infected fruit bats reported in India and Bangladesh outbreaks. Contact with secretions and excretions of patients reported as probable mode of transmission in Bangladesh
Epidemiology
A newly described human pathogen. The first human cases occurred in a zoonotic encephalitic outbreak between September 1998 and June 1999 in Malaysia and Singapore. Mortality was up to 40%. Bats of the genus Pteropus are reservoirs for Nipah virus in Malaysia. The disease caused a relatively mild disease in pigs. No new cases reported in Singapore or Malaysia since then.
Further outbreaks of Nipah virus infection have occurred elsewhere, mainly in western Bangladesh and also West Bengal, India.
- CSF abnormal in up to 75% of patients with lymphocytic pleocytosis and elevated protein.
- Magnetic resonance imaging showed distinctive changes of multiple discrete and small high signal lesions, best seen with fluid-attenuated inversion recovery (FLAIR) sequences.
- Serology is used for diagnosis. Paired samples demonstrating seroconversion confirms the diagnosis. A single sample with a titre of >1:400 is suggestive of acute infection.
- Reverse-transcriptase PCR in CSF and tissue.
Supportive
- Role of ribavirin uncertain.
