A teenage girl in Oregon has been hospitalized after contracting the bubonic plague, according to state officials.
The state department of health reported that the girl acquired the disease from a flea bite while on a hunting trip. She fell sick by October 21 and was hospitalized in Bend on October 24, where she remains in the hospital’s intensive care unit.
Plague is an extremely rare disease, though there has been more activity in the US than usual of late. Every year, the US records about a dozen plague deaths. According to the latest data from the Centers for Disease Control and Prevention, there were 11 cases and three deaths in six states in just five months, between April and August.
In Oregon, only eight human cases have been diagnosed since 1995, and no deaths have been reported.
The disease is caused by the bacterium Yersinia pestis, which spreads like this: Wild rodents — chipmunks, mice, squirrels — can carry the bacteria. The fleas that live around them feed on them and pick up the bacteria, spreading it to other mammals they bite, including humans.
People typically get plague when they're bitten by an infected flea — which is exactly what happened in Oregon. Other, less common ways to get plague include handling infected animals or coming into contact with a patient who has a form of plague (known as "pneumonic plague") that infects the lungs. But it's important to note that most plague is spread from animal to human, not person to person.
Bubonic plague infects the lymphatic system, causing the lymph nodes to painfully swell up and feel tender. These swellings, known as buboes, typically pop up in the groin, neck, and armpits. A blackish pustule will also pop up at the site of the flea bite, and hemorrhaging can occur underneath the skin, causing it to blacken.
After the plague bacteria incubates in the body for one to six days, people begin to develop symptoms that seem like the flu — fever, chills, aches, vomiting, and nausea. If untreated, the disease causes death in 66 to 93 percent of cases. And plague can kill pretty quickly, sometimes within a day or two of getting infected.
In the antibiotic era, the story is different. The mortality rate is about 16 percent in people who are treated with drugs (usually streptomycin or gentamicin). Antibiotics are most effective when they're given soon after infection, so people who get the drugs quickly recover. Those who aren't diagnosed quickly enough or who don't have access to medical care can still die from this disease.
To learn more, read our plague explainer.