The Centers for Disease Control has confirmed that plague caused the death of a Grand Canyon National Park wildlife biologist earlier this month.

Eric York was found deceased in his residence on the South Rim on November 2.

Last week the National Park Service announced that plague was the probable cause of his death based on preliminary laboratory tests conducted by the Arizona Department of Health Services and the CDC.

Park officials announced today that additional CDC tests have determined that the strain of plague that infected Mr. York is the same strain of plague that infected a mountain lion that he had direct and recent contact with. These tests support other evidence that the mountain lion was the source for the biologist’s infection.

Plague is a rare, but sometimes fatal, disease caused by the bacterium Yersinia pestis. It is primarily a disease of animals, but it can be transmitted to humans through the bites of rodent fleas or by direct contact with infected animals. In rare cases, pneumonic plague can spread person to person through aerosolized respiratory droplets (e.g. coughing, sneezing). According to the CDC, transmission of plague from person to person has not been observed in the United States since 1924.

Plague is considered endemic in northern Arizona at elevations above 4,500 feet. While an average of one or two human cases of plague are reported each year in Arizona, there were no human cases reported from 2001 through 2006 in the state. Increased plague activity in Arizona was reported in 2007 to public health officials.

A memorial service for Mr. York was held last Saturday in Massachusetts. His family has identified three charitable groups that friends can contribute to in Mr. York's name:

1) Felidae Conservation Fund, 14 Cove Road, Belvedere, CA 94920; 2) The Wildlands Fund, Division of Massachusetts Fish and Wildlife, attn: Julie, 1 Rabbit Hill Rd. Westboro, MA. 01581; or 3) The Grand Canyon Association, attn: Brad Wallace, P.O Box 399, Grand Canyon, AZ 86023.