Five-year study to assess risk of tickborne illnesses in Pennsylvania
The survey, which started in July 2018 in coordination with county governments, is part of the Pennsylvania Lyme Disease Task Force recommendations for combatting the growing incidence of Lyme and other tick-borne diseases. It is funded annually through the state budget.
“Lyme disease affects thousands of Pennsylvanians every year, but ticks are also known to carry other pathogens that could infect humans. This survey will provide important data that will help us better understand these arachnids in our environment and inform Pennsylvanians on how, when and where to avoid getting bitten by a disease-carrying tick,” said DEP Secretary Patrick McDonnell. “We want everyone to enjoy the outdoors and take the proper precautions to avoid contact with ticks, and we are proud to support the Lyme Disease Task Force’s efforts to protect Pennsylvanians.”
“Lyme disease is a major public health concern in Pennsylvania,” Secretary of Health Dr. Rachel Levine said. “Many people believe that Lyme disease, and the ticks that carry the disease, can only be found in wooded areas. However, I know personally, as do many others, that ticks can be found in your backyard, where you walk your dog, or the local park. These surveillance efforts will help us to share with all Pennsylvanians the importance of taking steps to protect yourself.”
The survey is taking place in every county in Pennsylvania to track ticks’ habitats, life stages and peak activity levels and to test them for human pathogenic diseases. Additionally, 38 counties are conducting a specific survey of nymphal blacklegged (Ixodes scapularis) ticks, which can transmit Lyme Disease to humans.
Ticks are collected using white felt drags that sample low-lying ground cover and understory vegetation for questing ticks.
Fall and winter surveillance focused on analyzing adult blacklegged ticks for emerging and changing disease burdens in public use habitats across Pennsylvania, such as parks, playgrounds or recreational fields.
The spring and summer surveillance will focus on collecting three tick species: the blacklegged tick in its immature nymphal stage, when it most often infects humans with Lyme disease, as well as human babesiosis and human granulocytic anaplasmosis; the adult American dog (Dermacentor variabilis) tick, which transmits Rocky Mounted Spotted Fever and Tulameria; and adult lone star (Amblyomma americanum) tick, which transmits Ehrlichiosis and Tularmeria.
The nymphal stage of the blacklegged tick causes the most tickborne illness in Pennsylvania due to its size and activity period. It is significantly smaller — about the size of a poppy seed — than the adult and therefore less likely to be discovered on the human body.
“The nymphal stage of the blacklegged tick’s lifespan overlaps with people enjoying the outdoors in the spring and summer,” McDonnell said. “Tracking and testing them at this stage is extremely important because it will allow us to more accurately pinpoint when and where risk of human illness is most prevalent and help prevent cases of Lyme disease in the future.”
Since July 1, 2018, DEP collected 3,663 adult black-legged ticks for testing.