red by the monkeys is very short (five to 10 kilometres). So we need to consider other potential species that may carry the ticks, including leopards and chital as the study (by Walsh et. al) indicates.”
Leopard (P. pardus) abundance and relative abundance and chital (A. axis) abundance were also associated with outbreak risk. While neither of these species has been shown to be susceptible to the KFDV, both are known to host the KFDV-relevant ticks and distribute these vectors in the landscape, the paper said.
Kiran’s point also has context in terms of the affected communities’ close association with the forests and exposure to virus-carrying ticks circulating in wildlife.
For instance, wild animals like spotted deer, primates, Indian giant squirrel or Malabar giant squirrel, shrews, rodents and peacocks which carry the same ticks are common visitors to properties in forest fringe areas in Kerala where the Cholanaikka tribe lives. ”And some of the families live inside the forest and all their livelihood activities result in exposure to infected hard ticks that are reservoirs of KFDV,” Mujeeb Rahman of ATREE observed.
In Karnataka, smallholder families also collect dry leaves from the semi-deciduous forest to line the floor of their cowsheds and to get more quantity of cow dung manure through mulching. “Women also visit the forest for collecting firewood. This is also an activity that increases their exposure to ticks which usually live under the dry leaves. The mixed cropping pattern of the smallholders (e.g. banana and areca nut cultivation) also attracts primates. The paddy harvest season that also coincides with the increased presence of rodents matches with the KFD outbreak season,” shared Rahman.
Michael Walsh echoes Kiran and others in saying that the understanding of the KFD is stunted because little is known about which species comprise its wildlife reservoirs and how the virus circulates in nature. “We need to increase this knowledge base (and quickly) because the KFD outbreaks are rapidly expanding across the region and the infection ecology and effective epidemiological interventions are currently both insufficient to stem this growing problem,” he said.
“Moreover, the KFD is just a model example of a much larger problem globally, which is that we know very little about the infection ecology of many (probably most) zoonotic pathogens and therefore we cannot craft optimal epidemiological interventions. Developing surveillance within a One Health framework offers a tenable solution for the KFD, and other zoonotic pathogens, because it simultaneously recognises the connections between humans, animals, and the broader ecosystems in which they live so that both the pathways to better understanding and the solutions for control and prevention that are based on that improved understanding are fundamentally grounded in all three.”
Banner image: Road construction in progress in tea plantations in Annamalai hills, southern Western Ghats. Photo by P. Jeganathan/Wikimedia Commons.