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
Yellow fever yellow fever virus became the first human virus to be isolated. Yellow fever begins after an incubation period of three to six days. Most cases only cause a mild infection with fever, headache, chills, back pain, fatigue, loss of appetite, muscle pain, nausea, and vomiting. In these cases, the infection lasts only three to four days. In 15% of cases, however, people enter a second, toxic phase of the disease with recurring fever, this time accompanied by jaundice due to liver damage, as well as abdominal pain. Bleeding in the mouth, the eyes, and the gastrointestinal tract cause vomit containing