Health officials are warning pet owners to protect themselves after two people died from the plague, a disease that wiped out millions of people in the Middle Ages, in the US state of Colorado.
The victims died of suspected septicemic plague, which infects the blood stream and can quickly result in organ failure.
Doctors and health department representatives in the city of Pueblo are advising residents not to let their cats or dogs roam around outside because they can pick up fleas infected with the plague and bring them into homes.
Fleas are thriving this summer because of unseasonably cool and wet conditions, officials said.
A child who camped at Yosemite National Park in California last month was hospitalized with the plague too, it was announced this week.
The plague is a zoonotic disease, meaning it can jump between animals and humans. In the latest cases, it’s being spread by fleas carrying bacteria, which can spread to humans through contact with animals.
The Yersinia pestis bacteria normally incubate for two to six days before an infected person shows flu-like symptoms.
Most cases of plague are bubonic, which affects the lymph nodes and is the least fatal form of the disease. Pneumatic plague causes pneumonia and septicemic affects the blood.
These days it can be treated with antibiotics if it’s diagnosed early enough and there’s a vaccine, which is given to people likely to be exposed to the disease.
