Health authorities in Oregon have confirmed a case of bubonic plague in a teen. She is believed to have contracted the disease from a flea bite. Officials say they think the girl was bitten and infected during a hunting trip this month near Heppner, which is located in northeastern Oregon in the foothills of the Blue Mountains.
She fell ill on Oct. 21 and was hospitalized days later. She is now in a hospital intensive care unit. There have been no other reported recent cases in Oregon, health authorities said.
Federal health agencies are puzzled by an upswing in cases of plague this year. There is usually an average of seven cases of plague in people in the United States each year, according to the Centers for Disease Control and Prevention. However, since April 1, there have been at least 11 cases of plague in humans in the United States, with three of them being fatal. The cases have occurred in residents of Arizona, California, Colorado, Georgia, New Mexico, and Oregon, the CDC said. "It is unclear why the number of cases in 2015 is higher than usual," the CDC said in a statement.
Plague is an infectious disease caused by the bacterium Yersinia pestis. It is carried by wild rodents and transmitted by fleas. The fleas then spread the bacterium to other animals or humans through bites. Symptoms of plague include fever, chills, headache, weakness, and a cough.
There are three forms of plague. Bubonic plague affects the lymph nodes, causing them to swell up and blacken. Septicemic plague occurs when the bacterium infects the bloodstream. The most contagious form of plague is pneumonic, which infects the lungs. Plague is not transmitted from person to person except for the pneumonic form and then only if the patient is coughing.
Antibiotics can be used to treat all forms of plague if an infection is caught early. If the infection is left untreated, it is fatal in 66% to 93% of cases. Even with treatment, the mortality rate is about 16%, according to the CDC.