Oregon has reported a case of human plague, the first in the state in around eight years. The patient likely got infected from the pet cat who had developed symptoms, Deschutes County officials said.

Plague is a disease caused by the bacterium Yersinia pestis that affects humans and other mammals. Humans typically contract the disease when bitten by a rodent flea that carries the plague bacterium or by handling plague-infected animals.

The officials noted that plague occurrence is rare in Oregon, with the last case reported in 2015. Squirrels and chipmunks are the primary carriers of plague in Central Oregon, although mice and other rodents can also transmit the disease.

"All close contacts of the resident and their pet have been contacted and provided medication to prevent illness," said Dr. Richard Fawcett, Deschutes County Health Officer in a news release.

Types of plague:

Plague can manifest in three clinical forms: bubonic, pneumonic, and septicemic. Bubonic plague, characterized by swollen lymph nodes, is the most common form of plague and generally has the highest survival rate. It usually results from the bite of an infected flea.

Septicemic plague occurs when the bacteria enters the bloodstream, leading to tissue destruction, gangrene, and organ failure. It may develop from untreated bubonic plague.

Pneumonic plague, on the other hand, develops when the bacteria infects the lungs. It is the least common, yet most dangerous form of plague. If the infected person develops plague pneumonia, they can release droplets of plague bacteria into the air through their cough. Inhaling these bacteria-laden droplets can result in pneumonic plague, and it is the sole method by which plague spreads between people. However, it usually requires direct and close contact with the infected individual.


The signs of the disease depend on the type of plague. Patients with bubonic plague may develop fever, headache, chills, fatigue, and swollen and painful lymph nodes (called buboes). In septicemic plague, patients may exhibit symptoms such as fever, chills, severe weakness, abdominal pain, shock, and skin bleeding. Additionally, the skin and other tissues, particularly on the fingers, toes, and nose, may darken and undergo necrosis. Patients with pneumonic plague may experience shortness of breath, chest pain, cough, fever, headache, and weakness.


Although a serious illness, plague can be effectively treated with antibiotics. Patients who seek prompt and appropriate treatment have a greater chance of full recovery. Those individuals who had close contact with severely ill pneumonic plague patients may undergo evaluation and potential observation. They may also be administered preventive antibiotic therapy, based on the nature and timing of personal contact.


There is no vaccine for preventing plague in the U.S. However, the illness can be prevented by following simple preventive measures:

  • Keep the house and surroundings free from rodents.
  • Use rodent repellents if you are exposed to rodent fleas during outdoor activities like camping, or hiking.
  • Keep your pets safe from fleas. If the pets become sick, seek immediate care from a veterinarian.
  • Wear protective gloves while handling or skinning infected animals.