Allegheny County’s tick collector works to assess Lyme disease risks
After dragging a swath of white cloth the size of a doormat through the forest duff along a shaded, onetime bridle trail that is now well used by walkers and joggers in Hartwood Acres county park, Leah Lamonte had her tweezers out.
Ms. Lamonte is the vector control program coordinator for the Allegheny County Health Department, and the specks she plucked from the “drag cloth” last week looked like smudges of finely ground black pepper — except they were moving.
As she delicately grabbed each tiny crawling dot and dropped it into a clear plastic vial filled with alcohol, she explained that she was collecting ticks, especially blacklegged ticks, the kind that carry Lyme disease and pass it to thousands of Pennsylvanians every year.
“Here’s one crawling on me right now,” she said as she crouched near a rotting log and pointed to her left wrist before calmly tweezing the larva and dropping it into the vial. It was a real-time reminder that ticks are not at all interested in practicing social distancing.
Ms. Lamonte gathers the tick larva, tick nymphs and adult ticks for a statewide tick surveillance program that is part of a five-year statewide study started in 2019 to assess the human health risks from tick-borne diseases. This is the first year Allegheny County has participated in the state tick program, which is funded through a $4,500 grant.
“We’re trying to drag for ticks at every single county park so that by the end of the summer we have a good representation of what’s going on in the parks,” Ms. Lamonte said. “I can pretty much guarantee that you can find ticks in every one of the city and county parks because we’ve dragged them all. And I assume anytime I am in a park it is possible I have been exposed to Lyme disease.”
Twice a week, Ms. Lamonte visits city and county parks, hiking and dragging her cotton or felt sheet through the tall grass and brush in wooded areas or along the edge of fields, trying to find, count and collect the blood-sucking ticks everyone else wants to avoid.
The vials of ticks are labeled with the location and park name and sent to the state Department of Environmental Protection laboratory in Harrisburg, where they are tested to determine whether the bugs are carriers of Lyme disease or some other pathogen.
Ms. Lamonte said the tests show 25% of blacklegged ticks in the nymph stage of their two-year life cycle carry Lyme disease and 50% of adult ticks have it. Those percentages are consistent with findings across the state.
Adult blacklegged ticks are twice as likely to have the Lyme disease because they’ve had two “blood meals” instead of one, Ms. Lamonte said.
The tick, a biting arachnid in the spider family, requires a blood meal from a host before it can change from larva to nymph and another between the nymph and adult stages. The white-footed mouse is the preferred and most common host for early stage ticks, while adult ticks often attach to deer for their third blood meal, or to humans.
But most tick-borne illnesses are transmitted to humans during the tick’s nymphal stage because the nymphs are more common during the spring and summer months when people are outside. Also, due to the nymphs’ pinhead small size, it’s harder for people to detect once it attaches itself.
Lyme disease can be transmitted to humans when a tick attaches itself for 36 to 48 hours. Symptoms can resemble those of a bad flu: fatigue, chills and fever, headache, muscle and joint pain. The disease can be treated with antibiotics, but left untreated it can cause arthritis pain in joints, numbness, facial paralysis, meningitis, heart arrhythmia and memory loss.
In addition to Lyme disease, 4% of blacklegged tick nymphs carry bacteria that cause anaplasma, a disease that causes fever, headaches, chills and muscle aches, and 1% carry babesia, a malaria-like disease caused by microscopic parasites that infect red blood cells.
It’s important for the public to know about the risks from tick bites, Ms. Lamonte said, especially because more people are recreating in the parks and outdoors due to the COVID-19 pandemic.
“We’re seeing a lot more people using the parks, but as long as people stay on trails they can be pretty safe,” she said. “I tell people to
think like a tick. They like cool, moist, shaded areas on the edges of fields or lawns and woods. If you are hiking and stay in the center of a trail, you should be pretty good.”
Other prevention measures include use of insect repellents containing DEET, picaridin or oil of lemon eucalyptus; treating clothes, footwear and hiking gear with permethrin; showering as soon as possible after outdoor activities; and visually checking for ticks.
To remove an attached tick, use tweezers to grasp the tick as close to the skin as possible and pull away from the skin with steady pressure. If the mouth breaks off and remains attached, remove it with tweezers and wash the bite area with rubbing alcohol or soap and water.
Lyme disease, first identified in the U.S. in 1975 around Lyme, Conn., is a significant health concern. Between 30,000-60,000 cases of Lyme disease are reported by states to the U.S. Centers for Disease Control and Prevention each year.
According to the CDC, Pennsylvania has led the nation in the number of Lyme disease cases since 2011. Over the past five years, it averaged more than 10,000 cases a year. The state Department of Health reported 9,009 cases in Pennsylvania for 2019.
But studies, including two by the CDC, indicate the disease is woefully underreported, and actually affects more than 325,000 people annually, mostly in the Northeast and upper Midwest. Pennsylvania and New York are hot spots.
In Allegheny County, according to state Health Department records, the first case of Lyme disease was recorded in 1988, and the annual number of cases stayed below 30 until 2014 when they jumped to 822. In recent years, the number of cases has settled to around 400 annually. The 2019 case number for Allegheny County won’t be available until next week, according to Nate Wardle, a state health department spokesman.
Ms. Lamonte said the increase in Lyme disease cases coincides with the increase in the population of blacklegged ticks, also commonly called “deer ticks,” which are found in all 67 Pennsylvania counties.
“The blacklegged tick is established here now and that wasn’t the case 20 years ago,” she said. “Then it was the American dog tick, a native, that was most common. But the blacklegged tick population grew and pushed the dog tick out.”
She said two new species of ticks — the Lone Star tick and the Asian longhorn tick — have been found in other parts of the state but not yet in southwestern Pennsylvania.
The state has been proactive in addressing its tick problem. In 2014, Pennsylvania established a 20-member tick task force that proposed a program of prevention, public education and surveillance of tick-borne illnesses.
And in 2015, the Pennsylvania Department of Conservation and Natural Resources posted signs in 120 state parks and 20 state forest districts warning visitors about ticks.
Ms. Lamonte said the health department would like to see signs posted in all the city and county parks reminding park visitors about the risks from ticks.
“As a people, we are good at moving into tick habitat. Our urban sprawl and housing plans take us into what were once wooded areas,” Ms. Lamonte said. “People need to be aware that there are these ticks out here and they are carrying these pathogens that can make them sick.”