Richard K. Root, 68; Expert in the Treatment of Infectious Diseases

Richard K. Root, 68, a professor emeritus of medicine at the University of Washington and a recognized expert in the treatment of infectious diseases, died March 19 in the African nation of Botswana.

Root was on a wildlife tour of the Limpopo River when a crocodile pulled him out of a canoe. Root was dragged beneath the water and not seen again. His wife of 18 months, Rita O’Boyle, was in another canoe and saw the attack.

Root and his wife, residents of Seattle, were about halfway into a two-month stay in Botswana sponsored by the University of Pennsylvania and the government of Botswana. Root was teaching doctors and nurses how to treat AIDS and HIV-related illnesses, family members said.

A native of New York City, Root graduated from Wesleyan University and earned his medical degree at Johns Hopkins University in 1963. From 1985 to 1991, Root was the chairman of medicine at UC San Francisco. He also was the founding head of the department of infectious diseases at the University of Pennsylvania School of Medicine.