by Daniel J. Cameron, MD, MPH
In Wisconsin, between 2001 and 2015, “there was a 26-fold increase in the incidence of confirmed babesiosis, in addition to geographic expansion,” according to MMWR.  The report listed suburbanization, forest fragmentation patterns, and warming average temperatures as potential causes behind the surge.
The rising prevalence of co-infections in rodents may also be to blame for the rise in Babesiacases. When studying the Northeastern region, Diuk-Wasser from Columbia University in New York City found “the prevalence of co-infection tends to be greater in rodents, ranging from 6% to 41%, because they are exposed to multiple tick bites during their lifetime.”  Furthermore, she adds, “the prevalence of B. burgdorferi and B. microti co-infection ranges from 0% to 13% in nymphs and from 2% to 13% in adults.”