Colorado on alert after dead cat tests positive for the plague – weeks after Arizona man died from disease

A Colorado town is on high alert after a dead cat tested positive for the plague – mere weeks after an Arizona man died from the disease.

The domestic cat, which lived in Evergreen, about 30 miles west of Denver, was diagnosed with the plague but did not survive, Jefferson County Public Health officials said.

It was the first confirmed case of the plague in an animal in the county since 2023, officials said.

The plague is incredibly rare in America, with the Centers for Disease Control reporting an average of seven human cases annually, the majority of which occur in rural areas of the Western U.S., including northern Arizona and parts of New Mexico and Colorado.

It is a disease caused by the bacterium, Yersinia pestis, and spreads from flea bites or direct contact with infected animals. While it can be life-threatening without immediate treatment, it can be treated with antibiotics if caught early enough.

Plague occurs in three forms: bubonic, septicemic, and pneumonic, depending on whether the infection hits the lymph nodes, bloodstream or lungs.

Last month, an Arizona man who contracted the plague died from the disease. He was rushed to a medical center with severe symptoms, but died the same day. His autopsy later revealed the bacterium for plague.

Symptoms of plague in humans may include a sudden high fever, chills, headaches, nausea and swollen lymph nodes, health officials said.

Meanwhile, in pets, the disease presents as fever, low energy, loss of appetite and swollen lymph nodes.

“It’s not uncommon to see a few animal cases of plague in the warmer months in Colorado,” said Jim Rada, Jefferson County Environmental Health Director.

“Like with this case, sometimes our local veterinarians are the first to see plague when our pets get sick. In many ways, they are a first line of defense both in helping keep our pets safe from fleas that could make our pets sick and in treating them if they are exposed to plague.”

Colorado health officials said there are ways to reduce the risk of plague for both people and pets. They include: