Don’t handle or feed wildlife and you won’t get the plague, the state’s health department announced on Wednesday after a squirrel tested positive for the plague last week in Jefferson County.

“Plague has been present in Colorado since at least the 1940s, and cases in wild rodents in Colorado are reported most years,” said Jennifer House, the state public health veterinarian. “While we see most plague activity during the summer, the disease can be found in rodents year-round and sometimes spills over into other wildlife species as well as domestic cats and dogs.”

The Colorado Department of Public Health and Environment reported that a southwest Colorado resident received a plague diagnosis earlier in the summer after exposure to squirrels. It was the first such plague case in a human in five years. The person has since recovered.

Bites from infected fleas are the most common way to transmit the disease, but infection can occur through bacteria from animal tissue, fluids and respiratory droplets. Symptoms include fever, headache, chills, weakness, and tenderness and pain in the lymph node. Plague can cause death and there is no vaccine.

CDPHE advises against handling and feeding wildlife and to avoid allowing pets to make contact with wildlife, including dead rodents and rabbits. The department has found four plague cases in rodents this year, compared with five rodents and one flea in 2019. The highest number of recent cases dates to 2007, with 134 discovered plague infections, half of which occurred in rodents.