Foodborne Transmission of Nipah Virus, Bangladesh

Abstract

TOC summary line: Nipah virus was likely transmitted from fruit bats to humans by drinking fresh date palm sap.

Henipavirus susceptibility to environmental variables

“…This extended survival time may have contributed to the NiV outbreak in Tangail, Bangladesh in 2005 where there was a strong epidemiological link between human NiV cases and drinking raw date palm sap (16). Fruit bats are known to drink from the pots in which the sap is collected and fruit bat excrement in or on the pots is sometimes observed.…”

“…The pigs were probably infected by P. vampyrus bats that fed on fruit trees adjacent to the pig farms, either through direct exposure to urine or via saliva-contaminated partially eaten fruit dropped into the pigsties (4). In the Tangail outbreak, NiV transmission to humans apparently occurred via date palm sap (15,16). The sap may have been contaminated by urine, faeces or saliva from P. giganteus which are known to feed on the sap during harvesting.…”

“…HeV is restricted to Australia and of the seven outbreaks to date all have involved infection of horses from unidentified sources, with subsequent direct transmission to humans on three occasions (8,9,20). NiV outbreaks have occurred in Malaysia, Singapore, India and Bangladesh following various chains of transmission including intermediate host species (3), human-to-human transmission (2,13), possible bat-to-human transmission (10) and vehicle-borne transmission (16).…”

Nipah virus infection: current scenario

“…Nevertheless, in addition to these countries, the virus has been detected in fruit bats or the bats were seropsitive to NiV antibodies from Cambodia [79], Thailand [90], Indonesia [81], India [23,99], Madagascar in Southern Africa [41] and Ghana in West Africa [22,37]. P. giganteus is the only Pteropus species present in Bangladesh [59]. In the Naogaon (Bangladesh) investigation, 2 of 19 P. giganteus specimens had antibody against NiV.…”

“…Fruit bats (P. giganteus) are a nuisance to date palm sap collectors because the bats drink the sap at night from the clay pots used to collect the sap. The investigations by Luby et al [59] suggested that NiV was transmitted from P. giganteus to persons through drinking fresh date palm sap. Date palm sap is a national delicacy that is enjoyed by millions of Bangladeshis each winter.…”