Then local microbiologist Chua Kaw Ping isolated the Nipah. It is a paramyxovirus, a family of bugs whose members include those causing mumps and measles. Nipah's closest cousin is the Hendra, a fruit-bat virus which killed a trainer and 14 horses in Australia. It may be no coincidence that the initial cases in the Malaysian outbreak were reported in the town of Ipoh, known for its network of caves. While some early victims were from JE, most recent patients seem to be Nipah cases.
Scientists have yet to identify the route of infection, but clues still point to sick pigs.
The authorities banned the movement of hogs and horses, and have culled more than 615,000 of some 850,000 pigs targeted. Planes carrying infected mosquitoes may help spread the Nipah virus to unaffected states. More worrying to some scientists is the possibility that Nipah may already be entrenched elsewhere in the country. Hendra is believed to enter a dormant phase a year before erupting in its virulent form. The new scourge may behave the same way.