Social history of viruses of encephalitis, of which 105 were fatal, were recorded. A new paramyxovirus was discovered in a victim's brain; it was named Nipah virus, after the village where he had lived. The infection was caused by a virus from fruit bats, after their colony had been disrupted by deforestation. The bats had moved to trees nearer the pig farm and the pigs caught the virus from their droppings. Several highly lethal viral pathogens are members of the "Filoviridae". Filoviruses are filament-like viruses that cause viral haemorrhagic fever, and include the Ebola and Marburg viruses. The Marburg virus attracted widespread press attention
Lassa fever Lassa fever Lassa fever, also known as Lassa hemorrhagic fever (LHF), is a type of viral hemorrhagic fever caused by the Lassa virus. Many of those infected by the virus do not develop symptoms. When symptoms occur they typically include fever, weakness, headaches, vomiting, and muscle pains. Less commonly there may be bleeding from the mouth or gastrointestinal tract. The risk of death once infected is about one percent and frequently occurs within two weeks of the onset of symptoms. Among those who survive about a quarter have hearing loss, which improves over time in about half. The disease is