The largest study of its kind — focused on tiny ticks — is underway in Pennsylvania.

The PA Tick Research Lab, one of only three labs nationwide engaged in tick testing and research, is analyzing data from 30,000 tick exposures in Pennsylvania from 2019-2021.

The full study is not only compiling the tick intel, but is building prediction models designed to help reduce human exposure to ticks, and therefore lower future Lyme disease rates. That’s important because Pennsylvania is predicted to get warmer and wetter as a result of climate change, and ticks thrive in those conditions.

“We are trying to be on the leading edge of finding the next best way to combat the health crisis. This would be the first study — the largest sample size in any given state,” said Dr. Nicole Chinnici, laboratory director for the Northeast Wildlife DNA Laboratory, home of the PA Tick Research Lab. The lab is based at East Stroudsburg University and partially funded by the Pennsylvania Department of Health.

Pennsylvania has had the highest incidence of Lyme disease in the country in 11 of the past 12 years according to CDC data.

Firsts, in tick research

Chinnici, a certified wildlife forensic scientist who also has a doctorate in public health, has conducted research at the lab for eight years.

“[The study] is giving us a lot of valuable key information that we can turn around and use to educate the public,” Chinnici said. “We’ve been using a statistical approach to be able to predict where a tick would crawl and attach, based upon the type of activity you’ve been participating in.”

The results, she said, may be eye-opening for many.

“While a lot of people might think they’re most likely to encounter a tick in a state park,” Chinnici said, “in reality the most common exposure is in your own backyard.”

Predicting high-risk tick locations is just the beginning. Additional information generated by the tick prediction models relate to weather.

“If you look at areas that have high rates of tick-borne illnesses and tick exposures, it’s the Northeast and upper Midwest — and a lot of that has to do with our climate,” Chinnici said. “We have high relative humidity rates, and that allows ticks to extract moisture from the air to survive, so they don’t dry out. Ticks aren’t very good at surviving and adapting to dry heat or desert-like heat. The Northeast’s and upper Midwest’s temperate environment allow them to survive.”

The Environmental Protection Agency says the range of ticks is expanding in correlation with warming temperatures associated with climate change. Other factors supporting an expanding tick population are host species such as deer and white-footed mice, both of which are plentiful throughout Pennsylvania.

That’s why a second study underway at the PA Tick Lab focuses on white-footed mice in four Pennsylvania counties.

“They are one of the reasons Lyme has been spreading,” Chinnici said. “So we’re going to be vaccinating them against ticks and looking at how we can decrease the number of ticks feeding on these mammals, to ultimately reduce the number of ticks we’re seeing in the environment as well as the pathogens we’re seeing in those ticks.”

Chinnici and her research team are calculating the density of ticks in each area to track fluctuations.

The four Pennsylvania counties involved in the study are Monroe and Pike in the northeast and Crawford and Mercer in the northwest. Chinnici said they were strategically chosen: Those regions have the highest reported Lyme cases per 100,000 people. She said they’re working to get grant money to study more regions.

oth studies mark new territory for the lab — a move beyond information gathering and testing, into research.

“Our tick mitigation research is looking at strategies to reduce ticks and tick-borne illnesses,” Chinnici said, “and that’s one of our core missions — to be proactive instead of reactive to the pathogens we’re seeing and getting ahead of the bite.”

Data for the PA Tick Research Lab’s studies comes from a constant stream of old-fashioned letters received in the mail. The contents of those envelopes include ticks sealed in zipped plastic bags, accompanied by a numbered code that identifies that tick sample.

The lab’s website includes instructions on how to remove a tick, send it to the lab, and receive a pathology report (which reveals whether the tick was carrying Lyme or other pathogens) within 72 hours. While testing is free for Pennsylvania residents, there’s a fee for those out-of-state.

Since 2019, the lab has analyzed more than 100,000 ticks discovered by Americans nationwide. Testing relies on genetics and qPCR — the same technology used in COVID-19 tests. The data is available in real time on the website, broken down by state.

In Pennsylvania, 29% of the 65,135 ticks tested to-date were infected with Lyme or other bacteria.