Pennsylvania has one of the highest incidences of Lyme disease in the nation; more cases of this tick-borne bacterial infection were confirmed in the Commonwealth in 2019 than in all of New England.
Microbiologist Dannelle Tufts says the frequency of Lyme disease in Pennsylvania is likely due to the climate and the abundance of green spaces that are particularly hospitable to ticks and their hosts.
“In Pittsburgh, you can find deer walking down your street,” said Tufts, a vector-borne disease expert at the University of Pittsburgh School of Public Health.
Deer do not carry Lyme disease, although they are a food source for adult ticks that meet their mates by feeding on deer blood. They then produce up to 3,000 eggs.
While Pennsylvania accounts for a large percentage of the country’s Lyme disease cases, the incidence of the disease has been increasing in North America for decades.
Global warming is partly to blame; milder winters are easier for ticks and their hosts to survive. Additionally, deforestation means that wild animals that have lost their habitats now live in cities.
“I know people who have, you know, raccoons and opossums in their backyards that eat cat food that they leave out,” Tufts said, noting that those animals frequently harbor ticks. .
To avoid Lyme disease, Tufts advises people to apply DEET insect repellent outdoors. Also, they should check themselves, their children, and their pets for ticks.