The Nipah virus is a newly identified member of the paramyxovirus family. It was first identified in Malaysia around 1998 near the Nipah Sungai River, from which it derives its name. This virus has the potential to cause a pandemic in humans as it can infect a wide range of hosts such as pigs, humans, and fruit-eating bats. Fruit-eating bats were identified as the source of this virus.
This virus
is found in date palm growing areas of India, Malaysia, and Bangladesh. Symptoms
typically appear around 3 weeks after infection. Symptoms are vague yet fatal. Symptoms
such as fever, headache, encephalitis, and respiratory illness, diagnosis can
be challenging unless the infection occurs in Nipah-endemic regions. Infected
individuals often progress to a coma state followed by death.
NiV strains in Bangladesh and India differ from those in Malaysia, contributing to distinct epidemiological characteristics of the virus. Mortality rates are higher in India and Bangladesh compared to Malaysia.
Fruit-eating bats primarily feed on date palm trees. The infected raw date palm sap is the most common form of transmission of infection from bats to humans, as outbreaks coincide with the sap harvesting season. Bats may also contaminate the sap collection utensils with their excreta. Domestic animals may also serve as a route of transmission from bats to humans.
In India, major outbreaks occurred in areas near
Bangladesh's Nipah belt, including Siliguri in West Bengal and Nadia district.
In 2018, there was an outbreak of NiV in the Kozhikode and Malappuram districts of Kerala, a southern state on the west coast. This region is geographically distant from Bangladesh or West Bengal, where date palm sap consumption is uncommon. Here, the outbreaks occurred through secondary transmission, mainly human-to-human transmission.
The concern regarding Nipah virus infection in communities has escalated following recent findings indicating that bats inhabit date palm trees and mango and litchi trees. There is a potential risk of infection for individuals who consume such fruits.
Headlines across Indian newspapers attribute the primary cause of death for seven children in Malda district, West Bengal. This outbreak was first reported in China and Vietnam.
Treatment is usually supportive or symptomatic. Patients with severe pneumonia and acute respiratory failure must be supported by mechanical ventilation. Treatment with antiviral Ribavirin is controversial as it was found to be effective against patients infected in Malaysia but had no effect on infected patients from India. Nipah viral infection can be controlled by preventing contamination of date palm sap and creating awareness of the risk of date palm sap consumption and consumption of fallen fruits eaten by birds by humans. Person-to-person transmission can be controlled by isolating the infected person, following good sanitation and hygiene, and by contact tracing of the infected individual. Healthcare workers should take extra precautions due to the risk of exposure.
https://pubmed.ncbi.nlm.nih.gov/23092599/
