No, you weren't reading articles republished from the dark ages — 2015 marked a resurgence of isolated cases of plague in the U.S. Caused by a bacterium called Yersinia pestis, found in rodents and the fleas they carry, plague made the jump to humans in 16 reported cases in the U.S. this past year. Researchers from SUNY Downstate Medical Center in New York have used surveillance data of those reported occurrences to map the areas where public health agencies should be on the lookout for potential infections.
The results, published in PeerJ, are based on an algorithm that predicts the risk of plague in wild and domestic animals using factors such as such as altitude, precipitation during the driest and wettest parts of the years and proximity to populated areas, collected between 2000 and 2015.
Most human cases of plague in the past century have occurred in northern New Mexico, northern Arizona, southern Colorado, California, southern Oregon and western Nevada, according to the CDC.
"The findings can be used by public health agencies to target specific areas for enhanced plague surveillance within areas and counties predicted to be at high risk, as well as by other research teams to direct the sampling of local wildlife populations for the identification of Yersinia pestis in wild animals that find themselves in close proximity to humans and human developed landscapes," Michael Walsh, PhD, assistant professor at SUNY Downstate's school of public health and first author of the paper, said in a news release.