Updated

A man hospitalized in critical condition in Bend, Ore., is likely to be suffering from the plague, health officials said Tuesday.

The man, aged in his 50s, became ill several days after he was bitten on the hand while trying to separate a cat and a mouse, The Oregonian reported.

Officials do not know whether he was bitten by the cat or the mouse. The cat died soon after the incident and its body has been sent to the Centers for Disease Control (CDC) and Prevention for testing.

According to the CDC, "Plague is an infectious disease that affects animals and humans. It is caused by the bacterium Yersinia pestis. This bacterium is found in rodents and their fleas and occurs in many areas of the world, including the United States."

The man, who lives in rural Crook County in central Oregon, was bitten June 2, but did not check himself into hospital until last Friday after he developed a serious fever.

Crook County Health Department communicable disease coordinator Karen Yeargain told The Oregonian that lab tests are being done to confirm whether the man has the plague. But she added that he is suffering from classic symptoms and is being treated with antibiotics.

The man initially presented signs of bubonic plague with swollen lymph nodes but is now showing signs of septicemic plague, when the bacteria multiply in the bloodstream, the newspaper reported.

Known as the Black Death, the plague is estimated to have killed more than a third of Europe's population during the middle ages.

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