The symptoms of JE are similar to those of dengue fever and include fever, headaches, vomiting, confusion and difficulty moving. When left untreated, this disease may cause swelling around the brain, coma, and even death. These symptoms will generally begin to occur between 5 and 15 days after being bitten by a carrying mosquito, and people often go without apparent symptoms. Only about 1 in 250 occurrences results in severe illness characterized by fever, headache, neck stiffness, disorientation, coma, seizures, spastic paralysis and death. The fatality rate for those experiencing all severe symptoms is generally 30%. Japanese Encephalitis is quite serious, and can also result in permanent intellectual, behavioural and neurological problems such as paralysis, recurrent seizures and the inability to speak. About 20%-30% of survivors will be affected in some way.