Reducing the Risk of Foodborne Transmission of Nipah Virus

Abstract

Nipah virus is a paramyxovirus whose wildlife host is large fruit bats in the genus Pteropus. Antibodies against Nipah virus and closely related Henipaviruses are common among old world fruit bats that live in Australia, across South and Southeast Asia and sub-Saharan Africa, but human infections with Nipah virus are uncommon. When humans are infected with Nipah virus 40 – 70 % die. People who are infected with Nipah virus can transmit the infection to other people. In the first recognized and largest Nipah outbreak, Nipah virus was transmitted from bats to pigs in Malaysia. A widespread outbreak among pigs led to infections among people who had close contact with infected pigs. The outbreak was arrested by culling over 900,000 pigs. Human Nipah virus infections have been identified in Bangladesh nearly every year from 2001 through 2014. The most common pathway of human Nipah infection is from drinking raw date palm sap. Pteropus bats frequently visit trees at night where sap is being collected and lick the sap stream as it flows into the collection pot. Drinking fresh date palm sap is a widely enjoyed seasonal delicacy in Bangladesh. Focused intensive interventions in limited areas discouraging people from drinking raw date palm sap or encouraging sap harvesters to use skirts to prevent bats access to the sap stream have reduced but not eliminated high risk practices.