Plague cases persist in the US, mostly in the West

Plague cases continue to occur in the U.S., with a New Mexico woman dying from the disease earlier this year, though officials say person-to-person spread hasn't been seen in over a century. Between 2000 and 2023, the U.S. reported zero to 17 human plague cases annually, totaling 122 cases with 15 deaths. Cases are primarily in the West, especially New Mexico and Arizona, with recent reports also in Oregon, California, and Nevada. The plague is caused by Yersinia pestis bacteria, typically spread through flea bites from rodents. Bubonic plague is most common, but pneumonic plague—the only form spread person-to-person—is considered most serious, though about 90% of patients survive with quick treatment.