Colorado man first in US to contract plague from a dog, study says

CDC also says July 2014 outbreak in which three other patients were sickened after man contracted disease from his put bull terrier was largest in 88 years

When a man in Colorado contracted the plague from his two-year-old pit bull terrier and spread it to four other people last summer, the resulting outbreak was the largest in 88 years - and the first known dog-to-human transmission of the disease, according to a new study released by the US Centers for Disease Control and Prevention.

The first patient to be identified with plague, described as a previously healthy middle-aged man, was first wrongly diagnosed with pneumonia. It wasn't until 10 days later, after the man's condition had precipitously worsened, that doctors realized he had contracted pneumonic plague. The disease, which attacks the lungs, is caused by the same bacterium that causes the more common bubonic plague and is typically passed to humans through flea bites.