The downside of nice weather is that ticks like it too. Blackflies and mosquitoes can take the fun out of a day of hiking or gardening, but a single deer tick can ruin a whole summer if it transmits Lyme or other serious disease. Fortunately, there’s a relatively new tool in the battle against deer ticks: mice.
As recently as fifteen years ago in northern NY state it was rare to find a single black-legged tick, commonly known as a deer tick, on your person even 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 socks and pants legs. Technically an invasive species in the north country, deer tick slowly moved up from the Mid-Atlantic and lower New England states. Based on anecdotal reports, there seem to be regional pockets where ticks are less prevalent than other places, but they are essentially everywhere in NY state now.
Ticks are arachnids, in the same category as spiders but way more dangerous. The deer tick is known to transmit Lyme disease as well as babesiosis, erlichiosis, anaplasmosis, Powassan virus and a few other serious illnesses. In fact it’s possible for two or more diseases to be transferred to people or pets by a single tick bite.
Our understanding of tick-borne illness has changed dramatically in the past few years. In July 2016, Dr. Nineveh Zubcevic, a tick specialist who teaches at the Harvard School of Medicine, presented new information on the topic. According to her, the red, expanding “bull’s-eye” rash (erythema migrans), long considered the hallmark of Lyme, is rare, occurs in 20% of cases at most.
In 2008 it was determined the Western Blot test was 36% false-negative, meaning 36% of the time, a person with Lyme will be told they do not have it. Dr. Zubcevic contends the false-negative rate might be even higher. Most tick-borne illness specialists recommend that treatment be given based on clinical symptoms, never based on blood tests.
An extensive 2014 tick study conducted in northern NY by Paul Smith’s College on behalf of the NYSDOH found that approximately 50 percent of ticks in our area are infected with Borreliaburgdorferi, the spirochete bacterium that causes Lyme. This flies in the face of ancient (2013) information that suggested only about 20% of deer ticks were infected. And researchers have identified two tick-borne microbes (one in 2013; one in 2016) closely related to Borreliaburgdorferiwhich can also cause Lyme, or at least a variant of it. Unfortunately, these newly identified pathogens do not show up on Lyme blood tests.
This isn’t to say we need to panic, though feel free to do so if you like. Let’s take action. Avoiding ticks is the first order of business. Ticks “quest” at the tips of tall grass or brush, waiting to glom onto the next warm body that brushes past. The Centers for Disease Control and Prevention (CDC) recommend using products containing 20-30% DEET on exposed skin. Clothing, footwear and gear such as tents can be treated with permethrin. Always follow label instructions!
Hikers, stick to marked trails, and never follow a deer trail. Treat your 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).
Shower and wash thoroughly every evening and then check for ticks. They like hard-to-see places such as the armpits, groin, scalp and the backs of the knees, so look closely in these areas. If you find a tick has latched onto you, 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 some time. Do not twist it or use heat, petroleum jelly or other home remedies to get it to release, as this can increase the chances of disease transmission.
While it was once thought ticks did not transmit Lyme for possibly as long as 72 hours, experts now say that while you definitely have 24 hours, beyond that is unknown. Other illnesses can be transmitted within minutes.
Homeowners can clear brush, weeds and tall grasses from the edges of yards. Ticks like to hide out under leaf litter (which is why sprays are not very effective against them), so maintaining a yard perimeter that’s raked clean can help discourage ticks.
Did someone mention mice earlier? Despite their name, deer ticks feed on—and infect—many wild critters, particularly mice. Deer do not carry Lyme, but they are tick farms which keep tick populations high. Actually, our native and ubiquitous white-footed mouse is considered the primary vector of Lyme. Each mouse can have between 25 and 100 ticks on it at any time.
It sounds logical, then, to wage war on mice. The problem is that if you trap or poison mice in your house or yard, all those ticks are going to drop off in search of another host. Yeah, not good. So let’s put those mice to work for us.
It seems that giving mice new beds may be the most effective way to reduce tick populations around the home. When mice have access to permethrin-treated nesting materials, tick mortality within that family is very high. Hypothetically, if one were to treat cotton balls, dryer lint, and fabric scraps with permethrin, one could then stuff said items into cardboard tubes (toilet paper, etc.). These could be left around the property where mice and other rodents would find and use the treated bedding, thus killing their ticks. Hypothetically.
The catch is that this may be a violation of NY State’s pesticide laws. Permethrin is labeled for “clothing and gear,” the latter having a rather loose definition. It is unclear. Given the seriousness of the tick-borne illness threat, I suspect that the NYSDEC may one day be providing an exemption to do this. In the meantime, read the label carefully and decide for yourself—please contact the NYSDEC if you need guidance.
At present there is only one product registered for such use in NYS. Appropriately called Damminix, it is a ready-to-go mouse-bed distribution system, consisting of permethrin-soaked cotton balls in tubes, which you put around your home, garage, shed, woodpile, and other likely rodent hideouts. It is a very small price to pay for a substantial reduction in tick density.
Early symptoms of Lyme disease can vary widely. Typically they include severe headaches, chills, fever, extreme fatigue, joint pain, and dizziness. But the first signs may be heart palpitations or confusion and memory loss, things once believed to occur only in late-stage Lyme. If you’ve been bitten by a deer tick and have any of these symptoms, see your doctor right away. (You may want to take this article with you.)
Please keep yourself and your loved ones ticked off, and have a great summer.
Paul Hetzler is a horticulture and natural resources educator with Cornell Cooperative Extension of St. Lawrence County.