Black flies bite, but ticks really suck. Enough complaining – that never helps.
After such a long winter, we are all grateful that spring has finally sprung, even though the price of warm weather seems to be the advent of biting insects. Swarms of mosquitoes can drain the fun from an evening on the deck, but a single black-legged or deer tick (Ixodes scapularis) can take the shine off an entire summer if it infects you with Lyme disease and/or another serious illness.
As recently as a decade ago in Northern New York it was rare to find a single deer tick on oneself after a long day outdoors. Now all you have to do is set foot in the brush to collect a whole set of them on your pant legs. Research has found that deer ticks were never here historically, even in low numbers, but moved-up from the mid-Atlantic states over the past few decades. Arguably they are an invasive species in Northern New York.
The newest tick on the block, however, is without question an invasive species. Native to Korea, Japan, eastern China, and a number of Pacific Island nations, it is known as the Asian bush or cattle tick (Haemaphysalis longicornis). It is also called the Asian longhorned tick, which is confusing because we already have Asian longhorned beetle. Plus, the bush tick has no long appendages of any kind.
In fact it is short on any distinguishing features. As Jody Gangloff-Kaufman of NY’s Integrated Pest Management Program writes, “Longhorned ticks are difficult to identify, especially in the younger stages. Adults are plain brown but look similar to brown dog ticks.” Tick identification services can be found here.
Closely related to our beloved deer tick, this Asian bush tick was discovered for the first time in the wild in North America in 2017 in New Jersey, where a pet sheep was reportedly infested with over a thousand of them. Since then it has spread to eight other states, including NY. Their high reproductive potential is one of the worrisome features of the species. They are all parthenogenic (asexual) females, meaning they churn out 1,000 – 2,000 eggs apiece without the bother of hooking up to mate.
Columbia News reported a good example of the new tick’s fecundity last December: When the Asian bush tick was first confirmed on Staten Island in 2017, surveys found their density in public parks was 85 per square meter. In 2018, the same parks had 1,529 per square meter.
Another concern is whether it is a vector of human and animal disease. In its home range, the bush tick is known to transmit a plethora of diseases including Lyme, spotted fever, Erlichiosis, Anaplasmosis, Powassan virus, tick-borne encephalitis virus, and severe fever with thrombocytopenia syndrome, similar to Ebola. As terrifying as this is, researchers have yet to find infected ticks in North America.
Experts disagree about the bush tick’s potential to spread illness. Dr. John Aucott, who directs the Lyme Disease Research Center at Johns Hopkins University Medical Center, has said that we should not extrapolate that because the bush tick carries serious illnesses in its home range, people here are at risk for the same diseases.
However, the deputy director of the Centers for Disease Control and Prevention (CDC)’s Division of Vector-Borne Diseases, Dr. Ben Beard, is quoted on the CDC website as follows: “The full public health impact of this tick is unknown. In other parts of the world, the Asian longhorned tick can transmit many types of pathogens common in the United States. We are concerned that this tick, which can cause massive infestations on animals, on people, and in the environment, is spreading in the United States.”
Right now the bush tick is downstate, but it is considered cold-hardy and will be heading our way. Though ticks only walk a few meters in a lifetime, they hitch rides on migratory birds. A study on deer tick range expansion led by Katie M. Clow of the University of Guelph in Ontario concluded that they are moving north at an average rate of 46 kilometers (28.5 miles) per year, aided by birds.
This isn’t to say we need to panic, though feel free to do so if you like. Avoiding this tick is done the same way we avoid deer ticks. Since ticks “quest” at the tips of tall grass or brush, waiting to glom onto the next thing that brushes past, hikers should stick to marked trails, and avoid following deer trails. Use products containing 20-30% DEET on exposed skin. Clothing, footwear and gear such as tents can be treated with 0.5% permethrin. Treat pets regularly with a systemic anti-tick product and/or tick collar so they don’t bring deer ticks into the home. Talk to your vet about getting your pets vaccinated against Lyme (sadly there is no human vaccine at the moment).
Check for ticks each evening after bathing. Ticks like hard-to-see places such as armpits, groin, scalp, sock hems, and the backs of the knees, so look closely in these areas. If you find a tick has latched onto you, prompt removal is critical. The CDC recommends you grasp it as close to the skin as possible with tweezers and pulling straight up until it releases. You may have to pull hard if it has been feeding for a while. Tick mouthparts commonly remain in the skin after tick removal; this is not a problem. Do not use home remedies to get a tick to release, as it induces it to disgorge back into you, greatly increasing the chance you may get sick.
Homeowners can help themselves. The CDC website states: “Maintaining a 9-foot distance between lawn and wooded habitat can reduce the risk of tick contact. Permethrin-treated clothing and DEET, picaridin, or IR3535 can be used as personal repellents. Follow all label instructions. Consult your veterinarian for recommendations specific to your situation and animals.”
Please keep yourself and your loved ones ticked off, and have a great summer.
Photo of Ventral view of female longhorned tick courtesy U.S. Centers for Disease Control and Prevention.