A team of researchers from Penn Medicine, (led by Michael P. Levy, PhD), studied bed bug reports in Philly between December 2008 and May 2011. Though they found that South Philly had the highest number of bedbug reports, it's not an isolated problem: bed bugs were found throughout the city, even in ritzier areas like Center City.
Perhaps more concerning than the geographical spread of bedbugs is the fact that Philly's bed bug problem is getting worse. During the study, bedbug reports increased about 4.5% per month, or 70% per year.
Researchers are trying to help combat the problem, and to that end they've found that bedbug reports go down in the winter, perhaps because the bugs need warmth to travel from place to place. Researchers hope that understanding this might help to determine the best time to treat for bed bugs.
· Penn Medicine Epidemiologists Find Bed Bug Hotspots in Philadelphia, Identify Seasonal Trends [UPenn]
· Bed Bugs Infest Philadelphia, According To Penn Medicine Report; Find Out What Section Fares Worse [CBS Philly]