Kyasanur Forest Disease review and vaccine prevention

Kyasanur Forest Disease (KFD) is a neglected, tick‑borne viral haemorrhagic fever of the Western Ghats (India) that has expanded geographically since its first recognition in 1957 in Shimoga district, Karnataka. The KFD virus is a tick‑borne flavivirus maintained in a complex sylvatic cycle involving Haemaphysalis spinigera ticks, small mammals, ground birds, and monkeys, with humans as incidental dead‑end hosts infected mainly through nymphal tick bites during occupational or recreational forest exposure. The spread from five endemic districts in Karnataka to newer foci in Goa, Maharashtra, Kerala, Tamil Nadu, and serological evidence in Gujarat and West Bengal has been attributed to deforestation, forest fragmentation, climate variability, and human encroachment, which alter host and vector communities and create high‑risk ecotones such as forest–agriculture edges. Please note the many similarities to TBE. Clinically, KFD is characterised as a biphasic illness with an acute febrile phase (5–11 days) marked by high fever, severe myalgia, gastrointestinal symptoms,...