Saturday, June 24, 2023

SafeTrails: Ticks in New England

Let’s face it, ticks suck. Figuratively and literally. It seems like every year the news features stories that claim "this will be the worst year for ticks," and every year, we ARE seeing more and more.

Unfortunately, they’re part of the outdoors, and while New Canaan Nature considers them “a strong and important link in the food chain,” I’d personally be happy to see them gone.

But, they're not going anywhere, and thanks to the effects of climate change (warmer winters with less snow), we will keep having "the worst year," over and over. Especially with the fact that ticks can be active any time of year when the temperatures are above freezing.

I think plenty of people are aware of Lyme disease and at least know some of the symptoms, but Lyme is just one of several diseases that can be spread by ticks in New England.

Let's first dive into the different ticks found here in the northeast (data from CDC.gov)

(See pic at further down for comparison of all the different ticks)


Black-Legged Tick (Ixodes scapularis): Also known as the deer tick, the black-legged tick is the primary carrier of Lyme disease in New England. It is a small tick with black legs and a reddish-brown body. The nymphs and adult females are usually responsible for transmitting: Borrelia burgdorferi and B. mayonii (which cause Lyme disease), Anaplasma phagocytophilum (anaplasmosis), B. miyamotoi (hard tick relapsing fever), Ehrlichia muris eauclairensis (ehrlichiosis), Babesia microti (babesiosis), and Powassan virus (Powassan virus disease). 


American Dog Tick (Dermacentor variabilis): The American dog tick is a larger tick species and can transmit diseases such as Tularemia and Rocky Mountain spotted fever. It has distinctive white markings on its back and is commonly found in grassy areas, along trails, and in open spaces where mammals frequent, and Adult females are most likely to bite humans.


Brown Dog Tick (Rhipicephalus sanguineus): While less common in New England, the brown dog tick can still be found in the region. It is a reddish-brown tick that primarily infests dogs. Brown dog ticks can transmit diseases like Rocky Mountain spotted fever (in the southwestern U.S. and along the U.S.-Mexico border), but may also transmit ehrlichiosis and babesiosis to both dogs and humans.


Lone Star Tick (Amblyomma americanum): The lone star tick is less prevalent in New England but has been expanding its range in recent years and is now widely distributed in the eastern, southeastern, and south-central United States. It is identified by a white dot or "lone star" on the back of adult females. While the lone star tick is not known to transmit Lyme disease, it can transmit other diseases and pathogens such as Bourbon virus (not known in New England), Ehrlichia chaffeensis and Ehrlichia ewingii (which cause human ehrlichiosis), Heartland virus (not seen in New England yet), Tularemia, and STARI. Also, growing evidence suggests that alpha-gal syndrome (red meat allergy) may be triggered by the bite of lone star ticks; however, other tick species have not been ruled out. The CDC further notes that this is "a very aggressive tick that bites humans. The adult female is distinguished by a white dot or *lone star* on her back. Lone star tick saliva can be irritating; redness and discomfort at a bite site does not necessarily indicate an infection. The nymph and adult females most frequently bite humans and transmit disease."


Groundhog Tick (Ixodes cookei): The groundhog tick is closely related to the black-legged tick and can be found in similar habitats. It primarily feeds on groundhogs and according to the Mayo Clinic, rarely bites humans. Groundhog ticks are known to transmit Powassan virus disease, which is a rare but potentially severe tickborne illness.


Asian Longhorned Tick: Not really found in New England--yet--but probably coming soon, and will be bringing more anaplasmosis, ehrlichiosis and rickettsiosis.



Tickborne Diseases
So now that we know that there's plenty of different species of little blood suckers out there, let's briefly discuss some of the different diseases they can spread. You'll see--which is is great for us that have to try to diagnose these conditions--that the symptoms are very similar and often very nonspecific, such as fevers, chills, and muscle/joint pains, and in some cases very mild. And, it's possible to catch more than one disease from a tick bite.
  • Lyme disease: Lyme disease is the most prevalent tickborne illness in New England and is primarily transmitted by the black-legged tick (also known as the deer tick). The symptoms of Lyme disease can range from mild to severe and may include fatigue, fever, headache, muscle aches, and may include the characteristic "bull's-eye" rash. Symptoms can occur 3-30 days after tick bite. Blood tests specifically looking for Lyme will often be normal for the first few weeks of an infection, but other lab abnormalities *may* be seen. If left untreated, Lyme disease can lead to complications affecting the joints, heart, and nervous system. There is wide controversy, even among infectious disease specialists regarding "chronic Lyme," and to whether or not there are long term effects and/or if long courses of antibiotics are required.
  • Hard Tick Relapsing Fever: Spread by the black-legged tick, this disease can manifest 3 weeks to 6 weeks after a bite and symptoms may be so mild that an infected person wouldn't notice, or could include fever, chills, fatigue, muscle or joint pains and relapsing fevers. This usually resolves on its own but can be severe in people with a compromised immune system.
  • Anaplasmosis: Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum, which is also transmitted by the black-legged tick. The symptoms include fever, headache, muscle aches, chills, and fatigue (like many of the other tick diseases), occurring 5-14 days after a bite.
  • Ehrlichiosis: Caused by Ehrlichia chaffeensis, E. ewingii or E. muris, this is spread by lone star ticks and black-legged ticks and is similar to anaplasmosis but may also include gastrointestinal symptoms.
  • Rocky Mountain spotted fever:  RMSF, caused by Rickettsia rickettsii, hasn't been too prevalent in New England, but it's an important disease to be aware of. If not diagnosed early enough, this can be fatal. Spread by the American dog tick, RMSF can cause high fevers, severe headache, fatigue, swelling around the eyes and hands, and then progress to confusion, coma and multi-organ system failure. A spotted rash is common, but is usually a later symptom and is absent in about 10% of cases.
  • Tularemia: This can be spread by several species of ticks, and in some cases, but infected deer flies. The CDC does say this is common in some parts of Massachusetts, but that's mostly in Martha's Vineyard. Caused by Francisella tularensis, symptoms (3-5 days after a bite but up to 21 days) can be nonspecific (fever, chills, fatigue), may include gastrointestinal symptoms (vomiting, diarrhea), but may also have a cough, swollen lymph nodes, eye pain, sore throat, and skin ulcerations. 
  • Babesiosis: Babesiosis is caused by microscopic parasites, Babesia microti, that infect red blood cells. Symptoms starting 1-4 weeks after bite include fever, fatigue, muscle aches, and sometimes anemia. Severe cases can involve a swollen spleen or liver, yellowish skin (jaundice) and lead to severe bleeding abnormalities and death.   
  • Powassan virus disease: While relatively rare, Powassan virus is a potentially serious tickborne illness found in New England. The virus is transmitted by the black-legged tick and the groundhog tick. Symptoms can range from mild flu-like symptoms to more severe complications, such as inflammation of the brain (encephalitis) or the membranes surrounding the brain and spinal cord (meningitis). There is no specific treatment for Powassan virus, so prevention becomes even more critical. 

Prevention Strategies: 
If after reading all of this you're as disturbed about the all the tick borne illness as I am after writing this, you'll want to avoid being bitten in the first place. Obviously, for outdoors people, avoiding the woods isn't an option. So here are some tips to help:
  1. Wear protective clothing: When venturing into tick-prone areas, wear long-sleeved shirts, long pants tucked into socks, and closed-toe shoes to minimize skin exposure. Tucking pant legs into socks might work for hikers, but trail runners and mountain bikers, not so much. I *have* been known to wear leggings specifically for summer use--they're designed to cover legs (or arms) and provide protection from the sun and insect. They're certainly a fashion statement, but if you know me, you know fashion isn't high on my priority list.
  2. Use insect repellents: Apply Environmental Protection Agency (EPA)-approved insect repellents containing DEET, picaridin, or IR3535 to exposed skin and clothing. You can also use permethrin on clothes (either spray on yourself or buy clothes with this already in the fabric).
  3. Perform tick checks: After spending time outdoors, thoroughly check your body and clothing for ticks. Pay extra attention to hidden areas such as underarms, groin, scalp, and behind the knees.
  4. Seek medical attention: If you develop symptoms consistent with tickborne diseases, seek medical attention promptly. Early diagnosis and treatment can help prevent complications.

If you do get bitten by a tick, remove it as soon as possible. Some diseases, like Lyme, need a tick to feed on you for longer than 24 hours before the infection can be transmitted. The data is still unclear about some of the other illnesses, but I've read that Powassan virus can be transmitted in as little at 15 minutes. The best way to remove a tick is to use a sharp pair of tweezers, grab it as close to the skin as possible, and pull straight out. Don't worry about "leaving the head." Just remove it as best you can, and if there IS anything left, your body will deal with it. You (or a healthcare provider) can do more local tissue damage by trying to remove anything that's inconsequential. Just clean the area with soap or disinfectant and keep it clean.

This image from TickSafety.com compares the different species with each other: 



Bottom line, do everything you can to avoid getting ticks on you in the first place.

If you want to geek out on more info, check out this great video from New England Journal of Medicine or this booklet from the CDC, otherwise, be safe out there!


Please remember, the information presented here, including but not limited to, text, graphics, images and other material contained on this website are for informational purposes only. No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment.



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