A California man has been confirmed to have contracted the plague earlier this week, the fifth case of the infamous disease in the United States this year.
The man, a resident of South Lake Tahoe, was the first case of plague in California in five years, according to the El Dorado County Department of Health. In July, Colorado also saw its first case in five years when a resident of the southwestern region, who has since recovered, became infected, according to the Colorado Department of Public Health and Environment. Navajo County public health officials documented a case in Arizona in late July. And two cases this year were reported in New Mexico, including one man who died.
Reports of plague may sound scary, but experts say the bacterial infection is not something to eat.
“Bubonic plague in the US is not the same scenario as the historic Black Death, and we do not have to be afraid of it in the same way,” said Susan Jones, a professor of ecology, evolution and behavior at the University of Minnesota College of Biological Sciences, said.
Although tragic, the cases this year are not uncommon, she said.
The US averages seven human cases of plague each year, according to the Centers for Disease Control and Prevention. In 2006, cases reached a height of 17.
Whether there are more annual cases than average may depend on what happens in rodents. Pests are caused by bacteria called Yersinia pestis, which are carried by flies that feed on rodents including prairie dogs and squirrels. People are more likely to be infected with plague if there is an outbreak of the bacterial infection in local wild rodent populations, Jones said.
‘Plague grows and blows in rodents. If many rodents become infected and die, plague can spread more easily to nearby people, ‘she said. With just five human cases reported so far this year, the US is still well within normal range, although deaths are uncommon.
“It’s unusual to have more than one plague-related death in the same year, and a few cases result in death,” Dave Morgan, a spokesman for the New Mexico Department of Health, told NBC News in a -post. If plague is caught early and treated with antibiotics, the chance of death drops to about 10 percent.
There had been no plague fatality in the U.S. since 2015, which had 16 total cases, four of which resulted in deaths, according to the CDC.
Although there is limited information about the death of the man in Rio Arriba County on the border of New Mexico-Colorado, the Department of Health of New Mexico reported the case as septicemic plague, instead of the much more common bubonic pest.
Both septicemic plague and bubonic plague are caused by the same bacteria; the name refers to what part of the body is affected, according to the Mayo Clinic. Bubonic plague occurs when the infection causes large, swollen lymph nodes, called buboes. Septicemic plague refers to an infection in the blood, and may be the first sign of infection if developing from untreated bubonic plague, according to the CDC. Still are contagious.
Only the third form of plague – pneumonic plague – can be spread from person to person. Pneumonic plague occurs when the infection enters the lungs, whether from untreated bubonic or septicemic plague, or from inhaling infected droplets from another person. It is the most serious form of the disease, says the CDC.
“Early diagnosis is very important,” Jones said, adding that in parts of the U.S. where plague is common, “doctors and veterans are on alert for symptoms of plague.”
Many symptoms of plague, she noted, such as fever, chills and headaches, can be confused with other diseases. Every year, however, epidemiologists make maps to track reports of the plague in rodents in the western US. If a person has spent time in the area in these areas and has these symptoms, doctors may be more inclined to consider plague.
The majority of cases occur in the Four Corners area, where Arizona, Colorado, New Mexico and Utah meet, although plague is detected in rodents across the West. According to Jones, this is due to the squirrels and prairie dogs that live in these areas and have pest-ridden meats. These bats can make their way to humans by striking pets that roam rural areas.
‘If you are outdoors in areas familiar with pests, do not adopt wild rodents or rabbits. Do not let your pets run around. Flea control applies to pets, and repels yourself when you walk or camp in the desert. Stay away from areas that have rodents, such as prairie dog towns, storage of caves and logs, ”Jones said. “And if you are concerned that you or your pet may be exposed to the plague, contact your doctor and veterinarian.”
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