An interactive map shows the states where people can still contract one of the deadliest bacterial diseases in human history.
It comes as the bubonic plague in Colorado gains more attention, as many assumed this medieval disease was a thing of the past.
Official U.S. data shows that outbreaks have occurred in 18 states over the past 50 years, mostly due to contact with rodents or bites from infected fleas.
Nationwide, there are approximately seven cases per year.
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The blackened fingers above belong to a man who contracted the plague in Oregon in 2012. He got it after being bitten by a cat
Infections are most commonly diagnosed in the western US, with New Mexico and Colorado having the most infections recorded over the past 50 years.
There have also been sporadic cases in the east of the country, although these are usually linked to international travel or laboratory accidents.
Three cases have been identified so far this year, including a person in Oregon who contracted the disease from his cat and a man in New Mexico who died from the disease.
The plague, which arrived in the United States in the 1900s, can be spread to humans through contact with rodents or through the bites of infected fleas or pets.
The most common form of plague in the US is bubonic plague, which causes warning signs within one to seven days of infection.
The other form, pneumonic plague, is caused by inhaling infected droplets and causes symptoms one to three days later.
Typically, patients survive only a few days without treatment, with a mortality rate as high as 60 percent among patients, which is linked to the disease that causes sepsis.
But it can be easily diagnosed through a mucus test and then treated with antibiotics to eradicate the infection.
The plague is known as one of the deadliest bacterial infections for humans. The disease swept through Europe in the Middle Ages, killing 50 million people, almost a third of the continent’s population.
This graph shows the number of cases and deaths from plague recorded each year since 2000
According to the CDC, 500 cases of plague have been diagnosed in the past five decades, from 1970 to 2022.
Three-fifths of those cases have occurred in New Mexico, while Arizona and Colorado account for another fifth of infections.
California, Oregon and Utah each recorded more than ten cases during this period, while Texas, Nevada, Idaho, Wyoming and Oklahoma recorded more than one.
According to the CDC, cases have been identified in everyone from infants to adults in their 90s, though most cases occur in people between the ages of 12 and 45.
Previous cases include a 10-year-old girl in Colorado who died from the disease in 2021. It was the first death in the state since 2015.
And a rare infection in a University of Chicago researcher working with the plague in 2009. It is thought they got infected in a lab accident.
A 59-year-old man who survived the plague in Oregon in 2012 but had to have his fingers and toes amputated said he felt “lucky to be alive.”
The map above shows the states where cases of the plague have been recorded over the past 50 years
Paul “Steve” Gaylord became infected when he tried to remove a mouse from the throat of a cat with the plague, which then bit him.
He was treated with antibiotics but spent almost a month on a ventilator and his family prepared for his death. He needed physical therapy after the infection and was fitted with prosthetic hands.
The plague arrived in the United States in the 1900s, carried by rodents on infected steamships.
The disease was widespread in western port cities for the next two decades, then spread to rats and mice in the countryside, where it remains prevalent to this day.
The last major outbreak in a city was in Los Angeles in 1925.