To date, there have been 157 cases and 58 deaths. The second virus, a new member of the paramyxovirus family could be similar to the Hendra virus found earlier in Australia. Japanese encephalitis has been confirmed to be the cause of 18 of the reported deaths. Further investigations are now underway to determine the role of the new viruses in the reported cases.
Acute encephalitis can lead to paralysis, coma and death.
In Malaysia, between 9 and 91 cases of JE are reported each year. Major outbreaks occurred in Langkawi in 1974, Penang in 1988 and in the Serian district of Sarawak in 1992. Japanese encephalitis virus usually affects pigs and is transmitted by the bite of culex mosquitos. Normally the disease is transmitted among pigs and it is only in exceptional circumstances that humans are involved. The initial stages of the current outbreak evidence pointed to JE because of the association of all the cases with pigs and piggeries.