While plague can now be treated thanks to antibiotics, it remains a deadly threat if detected too late or left untreated. This week, officials from El Dorado County—located just east of Sacramento, California—confirmed that someone visiting South Lake Tahoe became infected with the plague, likely being bitten by an infected flea. It’s rare to find a human case of plague in the U.S. nowadays (though it remains of particular concern in parts of Africa). According to El Dorado County officials, 41 rodents have been found infected with plague from 2021 to 2024. Pets are also susceptible to plague, so it’s also best to keep animals on leash when venturing into plague-prone areas.