The pneumonic plague sounds like something out of the Middle Ages, but it's still around. And according to a newly-released U.S. Centers for Disease Control and Prevention report, one Colorado man contracted the potentially fatal infection when his pit bull terrier coughed on him.

His dog started showing symptoms (including fever and a rigid jaw) last summer and was euthanized. But days after the dog's death, the owner was admitted to the hospital with a fever and a bloody cough. After 23 days in the hospital, he successfully recovered, along with three other people — one of his friends and two veterinarians — who were also infected.

Doctors are still baffled how a canine was able to spread the plague to humans. "Frankly one of the biggest surprises of this outbreak is the source," said John Douglas, who works at the Tri-County Health Department in Colorado and is an author of the study. "Primarily ... dogs don't get sick at all or they get a minor illness."

In the U.S., the pneumonic plague is found among prairie dogs in the Southwest, and an estimated 8 people contract it every year. The bacteria that causes all plague, Yesinia pestis, is also found in the infamous bubonic plague, spread by rats in the Middle Ages and responsible for wiping out millions of people in Europe. (Note: pneumonic = respiratory, bubonic = lymphatic)

Today, it's still a problem, albeit an isolated one. The World Heath Organization has reported nearly 24,000 cases of plague and 2,000 deaths from 1998 to 2009. But 98% of the world's cases occur in Africa.

[via Good Morning America

From: Good Housekeeping US