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The plague is one of the deadliest bacterial infections in human history, known as the Black Death in Medieval Europe, and killed an estimated 50 million people.
The disease is extremely rare, but it still exists today, and a New Mexico man was diagnosed with Died of the plague in March A person from Oregon was hospitalized due to the illness. Bubonic plague was diagnosed It is believed that he was infected by a pet cat in February.
It is transmitted by fleas that live on rodents. Symptoms usually appear within one to seven days of infection and include painful and swollen lymph nodes in the groin, armpits and neck (buboes), fever, chills and cough.
Plague affects humans and other mammals.
Plague is usually transmitted by the bite of rodent fleas that carry the disease-causing bacterium, Yersinia pestis, or by handling infected animals. Centers for Disease Control and Prevention.
Cats can infect humans directly if they get sick, while hardier dogs may just carry the fleas home to their owners, and humans can also get sick by inhaling droplets from an infected person or animal’s cough.
According to the CDC, the bacteria persists because it circulates at low levels among certain rodent populations: these infected animals and their fleas act as long-term reservoirs of the bacteria.
“The reason this virus hasn’t been eradicated is because it has an animal reservoir,” said Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center. I said in February“This bacterium can infect animals, and because we can’t treat all wild animals, it persists in the wild and occasionally causes infection in a limited number of humans.”
Plague occurs naturally in rural areas of the western United States, especially in Arizona, California, Colorado, and New Mexico. An average of seven plague cases are reported to the CDC each year in these areas. However, many more cases occur in parts of Africa and Asia.
Between 2010 and 2015, 3,248 cases were reported worldwide, including 584 deaths. who. The three most endemic countries are the Democratic Republic of the Congo, Madagascar and Peru.
There are three types of plague: bubonic, septicemic and pneumonic. Pneumonic plague infects the lungs, so there is a risk of direct person-to-person transmission. In a large outbreak in Madagascar in 2017So, there were 2,348 confirmed, probable, or suspected cases, and 202 deaths.
According to the CDC, the last urban plague epidemic in the United States occurred in Los Angeles between 1924 and 1925.
Modern antibiotics, usually with streptomycin as the first-line treatment, can prevent complications and death if given as soon as symptoms appear. This treatment is used for the two most common types of plague: bubonic and pneumonic.
“The reason antibiotics caused such widespread death and destruction in the Middle Ages is because they didn’t exist,” Barouch said. I said in February About the plague.
“It can cause serious illness, but if caught early it’s easily treatable with antibiotics, so it’s a very treatable disease now, and there’s no need to be as scared of it as people were in the Middle Ages with the Black Death,” he says. “Anyone who develops symptoms consistent with the plague — usually the early symptoms are fever, chills and swollen lymph nodes — should see a doctor, because in the early stages, the plague is easily treatable with antibiotics.”
Bubonic plague has a mortality rate of 30-60% if left untreated, while pneumonic plague is always fatal if left untreated. According to the WHO.
However, the bubonic plague strain High-level resistance to streptomycin It has been spotted in Madagascar.
Bubonic plague accounts for more than 80% of cases in the U.S. and is the most common form of infection. If left untreated, bubonic plague can turn into the more severe pneumonic plague, in which the bacteria spreads to the lungs and causes a rapidly progressive pneumonia.
There Plague vaccineBut they’re only recommended for high-risk people, like scientists who work directly with germs, says Dr. Harish Moorjani, an infectious disease specialist at Phelps Hospital, part of Northwell Health in New York. I said in February.
“Most people don’t need the vaccine,” Moorjani said.
a 2019 in Review The development of experimental plague vaccines suggests that researchers are exploring different approaches to developing an effective plague vaccination.
Because different vaccine designs induce different mechanisms of immunity, combining different types of vaccines may be able to overcome the limitations of individual vaccines and effectively prevent potential plague outbreaks, the authors conclude.
How do you protect yourself and your family?
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Important steps in preventing plague include eliminating rodent nesting sites by removing brush, rock piles, trash and excess firewood around the home, shed, garage and recreation areas.
Report sick or dead animals to the police or local health authorities. Do not pick up or touch them yourself. If you must handle a sick or dead animal, wear gloves.
If you live in an endemic area: Take extra precautionsUse insect repellents containing DEET to prevent flea bites and treat your dogs and cats regularly for fleas. Do not sleep with your pets as this increases the risk of plague infection. Finally, make sure your pets do not hunt or roam in rodent habitats such as prairie dog colonies.
CNN’s Jacqueline Howard and Mila Chen contributed to this report.
