ATLANTA, April 30 (UPI) -- A dog infected humans with the pneumonic plague for the first time in the United States, the Centers for Disease Control and Prevention said Thursday.
In June 2014, a 2-year-old American pit bull terrier became sick with a fever, jaw rigidity, drooling and neurological problems. The dog was euthanized one day later at a veterinarian's office in Colorado.
The dog's owner was hospitalized four days later with a fever and bloody cough, and was eventually diagnosed with the pneumonic plague. A friend of the owner and two workers at the veterinarian's office also became sick.
Blood samples drawn from all four people and the dog tested positive for Yersinia pestis bacteria, which causes pneumonic plague.
The four humans infected with the disease were all treated with medication.
The CDC says it's the first time it has ever reported a dog-to-human transmission of the disease. The report says dogs are typically asymptomatic or show mild symptoms of pneumonic plague and since one of the primary ways the disease is transmitted is through sneezing, dogs aren't likely to spread it to humans.
"For pneumonic plague, a more likely scenario would be you have a cat [play] with prairie dogs and infected fleas get on the cat," study author Janine Runfola of the Tri-County Health Department in Colorado told ABC News. "The cat gets sick and sneezes and coughs on its owner."
The CDC said about seven people in the United States become sick with the plague each year.