The first symptoms of primary amoebic meningoencephalitis "PAM", appear one to seven days after infection, including headache, fever, nausea, vomiting and a stiff neck, according to the CDC.
"Later symptoms include confusion, lack of attention to people and surroundings, loss of balance, seizures and hallucinations," the government agency's website states. "After the start of symptoms, the disease progresses rapidly and usually causes death within one to 12 days."