Kyasanur forest disease virus: viremia and challenge studies in monkeys
Kyasanur Forest Disease Virus (KFDV), discovered in 1957, is a member of the tick-borne encephalitis virus (TBEV) complex. Diseases caused by members of the TBEV complex occur in many parts of the world. KFDV produces a hemorrhagic fever in humans in South India and fatal illnesses in both species of monkeys in the area, the black faced langur (Presbytis entellus) and the bonnet macaque (Macaca radiata). Experimental infection of the langur and the bonnet macaque with early mouse passage KFDV strain P9605 resulted in a viremia of up to 11 days duration, peak viremia titers as high as 109, and death in 82 = 100% of the animals. Prolonged passage of the KFDV strain P9605 in monkey kidney tissue culture resulted in a markedly reduced virulence of the virus for both species; peak viremia titers in monkeys decreased by 2.5 to 4.0 log LD 50 (p= 0.001), and the mortality decreased to 10% (p= 0.001). In challenge experiments, monkeys previously infected with tissue-culture-adapted KFDV, or with the related Langat virus from Malaysia, were fully protected against virulent KFDV. These studies in non-human primates lend support to the idea that a live virus vaccine from a member of the TBEV complex may be broadly protective against infections by other members of the TBEV complex.
Corresponding author: Keerti V Shah
Competing interests: No relevant competing interests were disclosed.
Grant information: The Virus Research Center (renamed National Institute of Virology) was supported by the Indian Council of Medical Research, New Delhi and the Rockefeller Foundation, New York.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Copyright: © 2012 Shah KV et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
How to cite: Shah KV, Dandawate CN and Bhatt PN. Kyasanur forest disease virus: viremia and challenge studies in monkeys with evidence of cross-protection by Langat virus infection [version 1; peer review: 3 approved]. F1000Research 2012, 1:61
(https://doi.org/10.12688/f1000research.1-61.v1)
First published: 07 Dec 2012, 1:61 (https://doi.org/10.12688/f1000research.1-61.v1)
Latest published: 07 Dec 2012, 1:61 (https://doi.org/10.12688/f1000research.1-61.v1)