A Wyoming woman was diagnosed with pneumonic plague, a rare disease news reports said she was likely to have contracted from her domestic cats.
On September 15, health officials announced they had identified a “rare but serious” case of plague in a person who lives in northern Fremont County, Wyoming, south of Yellowstone National Park, according to a statement from the Wyoming Department of Health. The person appears to have been infected through “contact with sick domestic cats,” the statement said.
Related: 11 ways your beloved pet can make you sick
The plague, caused by the bacterium Yersinia pestis, is perhaps best known for causing the Black Death in Europe in the 14th century. The infection still occurs worldwide today, but is quite rare. In the United States, an average of about seven cases of plague occur each year, according to the Centers for Disease Control and Prevention (CDC). The disease is restricted to the western United States and is most commonly reported in New Mexico, Arizona, and Colorado. The woman’s case marks the seventh human plague case in Wyoming since 1978 and the first reported case in the state since 2008, the statement said.
People can contract the plague through flea bites or contact with infected animals or their tissues or body fluids. More than 80% of human plague cases in the United States are due to bubonic plague, a form of the disease typically spread by flea bites that causes swollen lymph nodes called “buboes”, according to the CDC.
The woman’s case is particularly unusual because she contracted pneumonic plague, the rarest and most severe form of the disease. It’s also the only form of the disease that can spread from person to person, says the CDC.
People can get pneumonic plague if they inhale infectious droplets spread by another person or an animal with pneumonic plague. People can develop pneumonic plague from other forms of the plague, including bubonic plague, if they aren’t treated right away.
Cats are “very susceptible” to plague, according to the CDC, and a known source of infection in humans. Cats with pneumonic plague “can pose a significant risk of disease to owners, veterinarians and others who come in contact with or come into contact with these animals due to possible aerosolization of bacteria,” it says on their website.
The plague can be treated with antibiotics, but early treatment is important to avoid serious complications, including death. Before the advent of antibiotics, the death rate from plague in the US was around 66%; today it is around 11%, according to the CDC.
The Wyoming Department of Health did not provide any further details about the patient or her current condition. A health official told Gizmodo that the woman is currently experiencing serious symptoms.
Officials are notifying people who have been exposed to the patient so they can receive antibiotics “post-exposure” to prevent disease, the statement said.
Originally published on Live Science.