India's current CHPV or Chandipura virus outbreak is largest in 20 years, World Health Organization (WHO) said recently. Indian government confirmed 245 cases of acute encephalitis syndrome (AES), including 82 deaths and of these, 64 are confirmed CHPV cases, it said. The disease, spread by sandflies, mosquitoes and ticks, has high fatality rate and there's no specific treatment available.