Ecology and epidemiology of rodent-borne viruses, arbovirus ecology and epidemiology, viral diagnosis, viral taxonomy, viral evolution. Recent major research emphasis is on the ecology of hantaviruses. Long-term field studies of these viruses in their natural rodent hosts are expected to provide information leading to prevention and control of these human pathogens. Coincident and ancillary studies provide knowledge about the mammalian hosts of these viruses as well as providing information about other rodent-borne viruses and about the mammals themselves.