Nipah virus emerged in 1999 in Peninsula Malaysia, where it caused a severe respiratory disease in pigs, some of which also displayed encephalitic symptoms. Humans became infected following contact with infected pigs and suffered a severe encephalitic disease. There were a total of 276 human infections in Malaysia and Singapore, with 106 deaths, a case fatality rate of 38.4% 1. The outbreak was finally contained by culling just over one million pigs at significant cost to the Malaysian economy.