As the virus passes along to the brain and then to the spinal cord, initial symptoms are fever, fatigue, headache, vomiting, stiffness in the neck, and pain in the limbs.
Sewaktu virus itu masuk ke otak dan ke saraf tulang belakang, gejala awalnya ialah demam, rasa lelah, sakit kepala, muntah, kejang di leher, dan nyeri di tangan dan kaki.