Scanning electron micrograph depicting a mass of Yersinia pestis bacteria. Photograph: Rocky Mountain Laboratories/NIAID/NIH 

A Colorado man is infected with the rarest and most fatal form of plague, an airborne version that can be spread through coughing and sneezing.

It is the first case of pneumonic plague seen in the state since 2004, said Jennifer House, a spokeswoman for the Colorado Department of Public Health and Environment. The man, who hasn’t been identified, may have been exposed in Adams County near Denver, health officials said in a statement. While House said the man has been hospitalized and treated, she wouldn’t release other details about his situation.

“He’s on treatment long enough to not be transmissible,” House said in a telephone interview. He may have contracted the illness from his dog, she said, which died suddenly and has also been found to carry the disease.

“We don’t think it’s out in our air,” House said. “We think it’s in our dead animal populations and dead rodent populations.”

Plague in all of its forms infects only about seven people yearly in the U.S. The disease occurs when a bacterium named Yersinia pestis infects the body, according to the U.S. Centers for Disease Control and Prevention. The difference between the pneumonic and bubonic varieties is that the bacteria take hold in the lungs in the first case, rather than underneath the skin through insect bites. Both types are treated with antibiotics.

The state is working “to investigate the source of exposure and to identify those who may have been exposed through close contact with the individual,” the Colorado Department of Public Health and Environment said in its statement. “Any individuals exposed will be recommended for antibiotic treatment.”

60 Cases

Colorado has had 60 cases of all types of plague since 1957, and nine people have died, the state said.

“The reaction is leaning toward people who are tired of the protection of prairie dogs on some level,” said Jim Siedlecki, director of public information of Adams County. “Most people look at them as cute little dogs on the side of the road, but in rural Adams County they are looked at as a rodent who damages crops and is potentially plague-ridden.”

Adams County, home to 470,000 residents, with 425,000 living in the Denver metro area, is one of Colorado’s fastest-growing counties and among the 20 fastest-growing counties in the nation.

Untreated plague is fatal, and antibiotics have to be given within 24 hours of the first symptoms to reduce the chance of death. Symptoms of the disease include fever, headache and chest pain, along with a pneumonia that develops rapidly causing shortness of breath, chest pain and bloody mucus, according to the CDC.

No Vaccine

There is no vaccine available for plague in the U.S. The bubonic form is the most common, best known for its outbreaks in the Middle Ages.

Colorado officials recommend that residents keep pets away from wildlife, especially dead rodents. The plague can spread from animals after a large die-off of prairie dogs, when fleas with the bacteria seek new hosts, according to the state.

“The message we’re trying to get out is that the plague bacteria is present here in Colorado, and to take necessary precautions to avoid getting infected,” House said. 

Source: http://www.bloomberg.com/news/2014-07-11/deadliest-rarest-form-of-plague-contracted-near-denver.html?cmpid=yhoo.inline