September 3, 2015
A recent report in MMWR, detailing the 12 cases of human plague reported this year, noted that the reason behind the surge remains unclear.
“Plague is a rare, life-threatening, flea-borne zoonosis caused by the bacterium Yersinia pestis,” researcher Natalie Kwit, DVM, an epidemic intelligence service officer at the CDC, and colleagues wrote. “During 2001-2012, the annual number of human plague cases reported in the United States ranged from one to 17 (median = three cases). It is unclear why the number of cases in 2015 is higher than usual.”