As the warmer weather comes with spring, so does a pest that seemingly grows in virulence each year: the tick.

This year, officials from the Pennsylvania Department of Environmental Protection are cautioning those venturing outside that “the rare but dangerous” deer tick virus, or DTV, has been detected at high levels in ticks for the first time in several areas of the state, and as close to Philly as Montgomery County.

DTV is a type of Powassan virus, which the CDC says has increased in recent years, mostly in the Northeast and Great Lakes regions from late spring to midfall, when ticks are most active. Pennsylvania began detecting DTV-positive ticks after it launched its five-year tick surveillance program in 2018.

What is deer tick virus?

The first reported case in Pennsylvania occurred in 2011. There are no medicines to treat Powassan nor vaccines to prevent it, though many of those infected with Powassan virus do not experience symptoms. If they do, symptoms emerge a week to a month after a bite:

  • Initial symptoms can include fever, headache, vomiting, and weakness.

  • More severe symptoms can include confusion, loss of coordination, difficulty speaking, and seizures.

  • The virus can cause encephalitis, an infection of the brain, or meningitis, an infection of the membranes around the brain and spinal cord.

  • About 1 in 10 people who get the severe form dies; half experience long-term health problems such as headaches, loss of muscle mass, and memory issues.

Pennsylvania has recorded only 10 Powassan virus cases between 2011 and 2020, but officials suggest that could rise as a separate threat from already widely transmitted Lyme disease.

» READ MORE: The most common ticks in the Philly region, and how to protect yourself

What other threats do deer ticks pose?

“Lyme disease has been present in all 67 counties for some time, and unfortunately, the prevalence of the very serious Deer Tick Virus appears to be increasing in some tick populations,” Patrick McDonnell, secretary of the state Department of Environmental Protection, said in a news release.

And now is the time: Deer ticks, also known as blacklegged ticks, start to become active when temperatures reach in the mid-30s and above, with April ushering prime time for the pests through fall.

Besides Montgomery, DTV has been detected in ticks in 15 other counties: Adams, Allegheny, Centre, Clearfield, Columbia, Dauphin, Fayette, Lebanon, Mifflin, Monroe, Schuylkill, Venango, Washington, Westmoreland, and Wyoming.

Clearfield, Centre, and Wyoming Counties are considered “hot spots” because “unusually high infection rates” of the deer tick virus were found in adult tick samples at Fisherman’s Paradise public fishing area on Spring Creek in Centre County, Iroquois Trail near Tunkhannock in Wyoming County, and Lawrence Township Recreational Park in Clearfield County.

The infection rate of ticks sampled exceeded 80% at each of those three locations; however, the infection rate outside of those areas is a fractional 0.6%.

Still, that combined with Lyme disease, which is present in all 67 counties, is enough that Cindy Adams Dunn, secretary of the state’s Department of Conservation and Natural Resources, cautions that “Pennsylvanians should learn about the threats posed by tick-borne diseases and take commonsense precautions so they can enjoy our abundant natural resources — and the many wonderful physical and mental health benefits of outdoor recreation — as safely as possible.”

Denise Johnson, the state Department of Health’s physician general, noted that there is at least one Lyme disease case for every 100 people in Pennsylvania annually.

Deer ticks, about the size of a sesame seed, can also spread babesiosis, a disease transmitted by parasites that infects red blood cells.

The Game Commission and Fish and Boat Commission said hunters and anglers should especially take note of the dangers posed by ticks.

How can I be safe from ticks?

Officials recommend that those going outdoors:

  • Apply repellents with permethrin to clothing, and EPA-registered insect repellents such as DEET to exposed skin.

  • Wear light-colored outer clothing; tuck shirts into pants, and pants into socks.

  • Walk in the center of a trail to avoid brush with low-growing vegetation and tall grass where ticks can cling.

  • After returning home, remove all clothing, take a shower.

  • Place clothing into a dryer on high heat.

  • Check your body in a mirror and don’t forget to look in the scalp, ears, armpits, belly button, and groin.

  • Examine gear.

  • Check pets.

  • If you find a tick, use fine-tipped tweezers, grasp the pest as close to the skin as possible and pull upward with steady, even pressure to avoid breaking mount parts off, which can remain in the skin, making sure to get the head.

  • Disinfect the bite and your hands with rubbing alcohol, an iodine scrub, or soap and water.

  • Ignore “folklore” remedies such as applying nail polish to the tick, smearing it with petroleum jelly, or using heat to force it out.