is a viral brain infection spread through mosquito bites. Illness ranges from asymptomatic infection, but 1 in 250 cases is estimated to be clinically evident with high mortality rate and severe neurological damage in survivors (approximately 30%) (PHE Green Book Halstead et al., 2008).
Usually occurs from 5 to 15 days after being bitten by infected mosquito. Flu-like symptoms develop but severe symptoms can include fever, fits, confusion, inability to speak, tremor, muscle weakness or paralysis.
One in every three people who develop more serious symptoms will die as a result of the infection.
This disease is transmitted from infected mosquito bite. It is not transmitted from person to person but the virus is passed to mosquito when they bite infected animals such as pigs and birds. Mosquitoes are active during and just after wet seasons though seasonal patterns vary both within individual countries and from year to year.
It is endemic in rural areas, where rice paddy fields and pig farming coexist, and epidemics occur in rural and occasionally in urban areas. Risk is also associated in areas with swamps and marshes. It is most common in rural areas throughout South East Asia, the Pacific islands and the Far East. 50% of endemic cases in Asia accounted are from China.
IXIARO® is licensed in the UK for individuals aged two months and currently recommended for use in the UK. The vaccine is inactivated and does not contain live organisms so cannot cause the disease against which it protects.