Japanese encephalitis virus is present in Asia and Oceania, from Japan to India, Pakistan and Australia. Outbreaks are erratic and spatially and temporally limited phenomena, occurring quite unpredictably. The virus is a leading cause of viral encephalitis in Asia, with 30 000 to 50 000 cases reported annually.
West Nile virus is a mosquito-borne flavivirus that is maintained in an enzootic cycle between mosquitoes and birds. Humans and horses are incidental dead-end hosts.
Sindbis virus is widely and continuously found in insects (the main vectors are Culex and Culiseta mosquitoes) and vertebrates in Eurasia, Africa, and Oceania. ECDC factsheet for health professionals
Poliovirus is highly contagious and infected individuals shed virus in the faeces and from oral secretions, thus the mode of transmission is person-to-person, both via the faecal-oral and the oral-oral routes.
The information contained in this fact sheet is intended for the purpose of general information and should not be used as a substitute for the individual expertise and judgement of healthcare professionals.
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