KFD: Infected people can't transmit it to others

Researchers from UK conducting research on Kyasanur Forest Disease (KFD) for the past two years with Indian scientists have said humans who contract KFD virus when bitten by an infected tick or by coming in contact with an infected animal are dead-end hosts.

The scientists, from the Centre for Ecology and Hydrology, said the infected humans can’t infect ticks or other people with the virus. Hence, they do not play a role in the onward transmission of KFD virus. The team is also working to prepare risk guidance on KFD which will contain details of which forest types, communities, activities are prone to KFD in the country.

As many as 340 confirmed KFD deaths were reported in the country over the last five years. The team also discovered that the disease is higher in fragmented and degraded forests because KFD first appeared at Kyasanur, Sorab taluk, 1957.

Speaking to DH, Bethan Purse, principal investigator from the UK NERC Centre for Ecology and Hydrology, Wallingford, said as part of the two-year Monkey Fever Risk project, the team comprising Sarah Burthe, co-investigator and wildlife ecologist, and Dr Frane Gerard, the co-investigator and senior earth observation scientist, visited KFD-hit villages in Thirthahalli, Sagar and Hosanagar taluks in the district recently.

She said human cases have increased significantly to around 500 a year. Between 5 and 10% of people who are known to be affected by KFD develop haemorrhagic symptoms and die.

Bethan said the team has visited Karnataka, Goa, Kerala and Maharashtra where KFD cases were reported to find out why the disease is prone to a few parts of the country in the last two years. Of the 27 persons who are part of the project, seven are from the UK.

Bethan said the data on the ecology and socio-ecology of the KFD system to test this hypothesis and to identify high-risk areas for the disease is not adequate.

Many ticks, wild rodent, bird and primate species are thought to have a potential role in the in transmission of the KFD virus.

She opined that there is a need to understand how the specific activities of local communities in the forest increase their risk of contracting the disease, and whether and how such activities could be avoided without harming their health and livelihoods. This is the main goal of the research, she explained.