Nipah virus; The henipa viruses, including Nipah virus and Hendra virus, are highly lethal, emerging, bat-borne viruses within the family Paramyxoviridae, that infect humans directly or via domestic animals that function as bridging hosts. Previous Nipah virus outbreaks were reported in Malaysia in 1998; hence in eastern India in 2001 and 2007, in Bangladesh almost annually since 2001, and in Kerala, India, in May 2018.
In Malaysia, transmission from bats to humans occurre through pigs as intermediate hosts. Pigs were putatively infected after consuming fruit; so that was partially consume by Pteropus vampyrus bats. In Bangladesh, transmission from bats to humans occur through consumption; hence of date palm sap contaminate by P. medius (formerly P. giganeteus), and subsequent human-to-human transmission has commonly observed.
Nipah viruses RNA
Initial wildlife studies in response to the 2018 Kerala outbreak; so focuse on insectivorous bats (Megaderma spasma), whereas a later survey focuse on P. medius and found that 19% (10/52) of the P. medius test had at least one biological sample with evidence of Nipah virus RNA using real-time reverse transcription polymerase chain reaction (RT-PCR).
However, a salient feature of the outbreak in Kerala was the superspreader, who; so while he was care for in hospital, infect most cases identify during the outbreak. Henipaviruses such as it warrant attention from the global health community because of their ability; hence to spread from person-to-person, although our understanding of which strains are most transmissible among humans, and why, is poor.
To provide guidance for sampling bats in India generally; also guidance for epidemiologic studies looking for animal exposures associate with Nipah virus spillovers in Kerala; so they systematically search the literature for records of studies of Nipah virus and henipaviruses in bat species known to occur in Asia, Australia, and Oceana.
More extensive data
They collated all records of Nipah virus shedding from bats (PCR) and Nipah virus exposure in bats (serology that likely includes cross-reacting henipaviruses). They use generalize boost regression of more extensive data on bats in Asia, Australia, and Oceana to make trait-base predictions of likely henipavirus reservoirs near Kerala.
Nipah virus has a wide host breadth in both reservoir bat species and recipient animal species. Therefore, identifying the reservoir in a new location can be challenging. They use a systematic literature search to collate data from previous studies of Nipah virus in bats. We then prioritize surveillance of bats in Kerala, and more generally in India, on the basis of these data.
In general, our analysis suggests Nipah virus-positive bats in this region tend to be herbivorous or omnivorous species whose geographic ranges overlap with tropical desert (arid) habitats, maximally extending to the northern limit of the tropical belt and overlapping with a high diversity of other mammal species.
Given that bats from arid habitats may forage more widely; so when water or food resources become limit in dry years, it is also possible that Nipah virus transmission may occur with increasing contact between multiple bat species mixing at higher densities around limit resources.