Archive for the ‘Ticks’ Category

Bears, Noro, and Lyme: What to Worry About (or not) on Your Thru-Hike

https://thetrek.co/bears-noro-lyme-worry-not-thru-hike/

Bears, Noro, and Lyme: What to Worry About (or not) on Your Thru-Hike

So, you’re planning to head out on trail for a long walk. Maybe even a thru-hike of one of the Triple Crown trails — the Appalachian Trail, Pacific Crest Trail, and Continental Divide Trail.

You’ve probably gotten a lot of questions from people who think you are out of your mind, many of which begin with, “Aren’t you afraid of…”

Veteran thru-hikers will tell you that while there are inevitable dangers on trail, stereotypical fears are usually overblown. Here’s a hard look at three common concerns on the trail—bears, Lyme disease and norovirus—how much you should (or shouldn’t) worry about them, and how to minimize their impact on your hike.

Bears

 

Let’s start with the bugaboo that friends and family fret about when they imagine you—a tasty human hors d’oeuvreout in the wild for six months.

Bears are a fact of life on all three Triple Crown trails. The American black bear (Ursus americanus) is common on all three trails, while the brown bear, aka grizzly (Ursus arctos) is found only near the northern reaches of the CDT. If you see a polar bear, Ursus marinus, you’re either taking a zero in a city with a zoo or considerably off course.

Grizzlies and black bears were once hunted to near extinction. Today they are thriving, with as many as 465,000 black bears and 200,000 grizzlies (mostly in Canada and Alaska) roaming the continent.

So, how dangerous are they? Here’s a clue: Most long-distance hikers consider bear sightings a highlight, not a nightmare. Consider these stats:

  • Between 2000 and 2019, there have been just 53 documented fatal attacks on humans by bears in North America, or about 2.8 per year.
  • Of those, just ten fatal grizzly attacks and 10 fatal black-bear attacks occurred in the Lower 48, or about one per year.
  • No fatal grizzly attacks occurred in states traversed by the AT; one occurred in a PCT state (California, but with this notable asterisk: a captive bear killed its handler); nine were in CDT states.
  • Of CDT-state grizzly attacks, six occurred in Yellowstone National Park (around four million annual visitors) or Grand Teton National Park (around three million annual visitors).
  • Of fatal black-bear attacks, four occurred in AT states, two were in CDT states, and none were in PCT states.
  • No fatal black-bear attacks occurred on the AT, PCT, or CDT. The two CDT-state black-bear attacks occurred far from the trail. Of the AT-state attacks, two occurred about ten miles from the trail (one in the Smokies; the other was the first recorded bear fatality in New Jersey history); the other two were at least 50 miles from the trail.

There is no reliable data on nonfatal attacks on or near Triple Crown trails. But considering the millions of people who annually visit some part of the trails — the Appalachian Trail Conservancy estimates that more than two million people visit the trail every year, for example, and some seven million people a year visit Yellowstone and Grand Teton national parks, traversed by the CDT — your chances of a dangerous bear encounter are vanishingly small, considerably less than one in a million. Statistically speaking, you’re about 60,000 times more likely to be killed by a human than a bear.

That said, it pays to be bear-smart.

  • The ATC now recommends that hikers carry food in a bear-resistant container approved by the International Grizzly Bear Committee. Canisters are required on significant portions of the PCT and CDT.
  • Learn how to properly hang a bear-bag. (Dangling a non-bear-proof bag from a spindly limb four feet from the ground does not count.)
  • Prepare and eat food away from your sleeping quarters.
  • Keep your dog in check. One study of black-bear attacks found that more than half involved an off-leash dog.
  • Educate yourself of how to respond if a bear does attack.

Conclusion: Be bear-smart, but your chances of having a negative encounter with a bear are extremely low, bordering on non-existent.

Lyme disease

If you are a CDT or PCT hiker, you’re mostly off the hook for this one, as incidence of Lyme disease is negligible in the West (though it is rising faster in California than in any other state except Florida).

But if you are an AT hiker, Lyme disease should concern you much more than bears. Believe it or not, one out of every 20 AT thru-hikers will contract this tickborne disease in 2019.

In fact, the AT passes through ten of the 15 states with the highest Lyme incidence (cases per 100,000 residents), according to 2017 statistics compiled by the Centers for Disease Control. The worst state may surprise you: Maine, with 1,850 cases, or 106 per 100,000 residents. But number three Pennsylvania is tops in raw numbers, with a whopping 11,900 cases, more than twice as many as the next two contenders, number 13 New York (5,155 cases) and number seven New Jersey (5,092). These AT states also rank in the top 15 for cases per 100,000 residents: number two, Vermont (1,092 cases); number five, New Hampshire (1,381); number six, Connecticut (2,051); number 11, Maryland (1,891); number 12, Massachusetts (410); and number 14, Virginia (1,657). Lyme disease is considerably less common in southern AT states so far — in 2017, 45th-ranked Georgia reported just 0.1 cases per 100,000 residents; Tennessee (0.2) was 42nd, and North Carolina (0.7) was 26th — but bites from the lone-star tick, Amblyomma americanum, can cause STARI, or southern tick-associated rash illness, which can cause similar symptoms.

cdc lyme disease appalachian trail

lyme disease appalachian trail

Possible erythra migrans rash, taken in emergency room in Reading, PA.  Clay Bonnyman Evans photo.

If caught early, Lyme disease is easily treated with common antibiotics such as Doxycycline and Amoxicillin. If left untreated, Lyme can cause serious, even life-threatening symptoms, including heart disease and partial paralysis. You do not want to mess around with Lyme.

But here’s the catch: the disease cannot be definitively diagnosed, even through laboratory tests, for up to six weeks.

“Antibodies against Lyme disease bacteria usually take a few weeks to develop,” according to the CDC. “During the first few weeks of infection, such as when a patient has an erythema migrans rash, the test is expected to be negative.”

Another bummer: The ticks most likely to transmit the disease are in the nymphal stage. They are teeny-tiny little pests, the size of a poppy seed or even smaller. Hard to find.

But don’t worry: Doctors in Lyme-endemic states are hip to all this. Rejected by a doc-in-a-box clinic because my fever was “too high” (104 degrees), I staggered into an emergency room in Reading, PA, during my 2016 AT thru-hike. There, the no-nonsense doc swiftly prescribed doxycycline based on a) my symptoms (including a non-bulls-eye rash) and b) circumstances, i.e., living in the woods and infrequently showering. It sucked, but after a few days of misery, I was on my way north.

You may have heard stories of a debilitating, ongoing illness called “chronic Lyme disease.” The CDC is skeptical of this alleged diagnosis, preferring the label “Post-Treatment Lyme Disease Syndrome.” The agency cautions that some treatments prescribed by doctors for the syndrome, including prolonged courses of antibiotics, are not effective and can cause long-term complications.

Your best bet, of course, is to avoid contracting Lyme (or STARI) in the first place. Here are a few good rules recommended by the ATC.

  • Wear clothes treated with permethrin. You can buy pre-treated clothes, spray them yourself or even send your gear to be treated by a company called Insect Shield.
  • Wear long pants and sleeves in tick territory. (Confession: Even after suffering the symptoms of Lyme, I couldn’t bear wearing long sleeves and pants while trudging through the mid-Atlantic inferno in high summer.)
  • Wear light-colored clothing.
  • Apply Deet-based insect repellent to exposed skin.
  • Do tick checks nightly. Recruit a pal to check, uh, the areas you can’t see yourself; make sure he or she is a really good pal, since the tiny nymphal ticks most likely to transmit Lyme are very hard to see.
  • Ask your doctor if she will prescribe a course of doxycycline or Amoxicillin prior to your hike. If you develop flu-like symptoms, take the antibiotics as prescribed, and you’ll save yourself the hassle and cost of going to a doctor who will simply prescribe the same medication.

Conclusion: Lyme-bearing ticks are be a lot smaller than a bear—800 million times smaller—but they should take up much more of your concern.

Norovirus

This nasty little bug is millions of times smaller than a tick, but it frequently causes distress and suffering among long-distance hikers.

Noro, as it is often referred to, is a tiny viral particle that causes diarrhea and vomiting. The most common cause of acute gastroenteritis in the United States, noro annually causes up to 71,000 hospitalizations and 800 deaths. It’s a tenacious little bugger that can survive on a dry surface for weeks.

There aren’t good statistics about the incidence of noro on trails — but the ATC typically puts out several noro warnings each year for AT hikers. It’s a people thing: the more crowded the trail, the more likely it is that the disease will be present. Suffice it to say that it’s common, and all-too-easy to contract by:

  • Having direct contact with an infected person.
  • Consuming contaminated food or water.
  • Touching contaminated surfaces, or consuming food that has touched contaminated surfaces.
  • “You can get norovirus,” according to the CDC, “by accidentally getting tiny particles of poop or vomit from an infected person in your mouth.” Yum.

Symptoms usually develop 12 to 48 hours after exposure and the illness usually runs its course in one to three days. Disturbingly, people may continue to “shed” the virus for up to two weeks.

 

 Instead of gross illustrations of norovirus, here’s a shot looking up from the bottom of Mahoosuc Notch in Maine.  Clay Bonnyman Evans.

It’s hard not to be filthy on trail — it’s part of the fun, right? But there are plenty of things you can do to reduce the likelihood of contracting a nasty case of noro on the trail.

  • Wash your hands, early and often. With soap and water (at least 200 feet from any water source). Antibacterial hand sanitizer isn’t as good as washing, but it’s better than nothing.
  • Don’t share food, water bottles or utensils.
  • Don’t shake hands. Fist bumps are not just an affectation!
  • Properly treat water.
  • Follow Leave No Trace guidelines for disposal of human waste.
  • Report outbreaks or incidence of norovirus. Email stomachbug@appalachiantrail.org to help the ATC notify hikers of outbreaks.

Conclusion: Norovirus is small—millions of times smaller than a bear or tick—but it’s brutal, and can cause miserable havoc on trail. You have a right to be worried about it, and don’t forget to wash your hands!

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**Comment**

A few corrections regarding the Lyme section:

  1. You are never “off the hook” with tick-borne illness.  Maps showing the locations of ticks have been used against patients for decades – and they are constantly changing due to migrating birds depositing them everywhere:  https://madisonarealymesupportgroup.com/2019/03/09/danish-study-shows-migrating-birds-are-spreading-ticks-their-pathogens-including-places-without-sustainable-tick-populations/.  Plus, there are many other pathogens you should be worried about besides Lyme:  https://madisonarealymesupportgroup.com/2017/07/01/one-tick-bite-could-put-you-at-risk-for-at-least-6-different-diseases/ (BTW:  the actual number is 18 and counting)
  2. As you read the paragraph based on CDC numbers of infected people, please remember these are notoriously low.  The actual numbers are frightening and it’s only getting worse.  https://madisonarealymesupportgroup.com/2018/02/24/one-million-predicted-to-get-lyme-in-2018-in-the-u-s/  Lyme/MSIDS is a true pandemic, showing no signs of slowing down.
  3. Regarding STARI – it looks, smells, and feels exactly like Lyme so don’t think it’s a walk in the park.  Shenanigans abound when it comes to the South and tick-borne illness.  For more on that debacle:  https://madisonarealymesupportgroup.com/2017/10/06/remembering-dr-masters-the-rebel-for-lyme-patients-who-took-on-the-cdc-single-handedly/, https://madisonarealymesupportgroup.com/2018/05/31/no-lyme-in-the-south-guess-again/
  4. I’m not sure what “Lyme is a very specific disease” means to this author but it is as vast and wide as you can imagine with symptoms all over the place. It’s unbelievable and had I not lived this nightmare on steroids, I probably wouldn’t believe it myself.  And rarely does Lyme come alone:  https://madisonarealymesupportgroup.com/2018/10/30/study-shows-lyme-msids-patients-infected-with-many-pathogens-and-explains-why-we-are-so-sick/ For the first time, Garg et al. show a 85% probability for multiple infections including not only tick-borne pathogens but also opportunistic microbes such as EBV and other viruses.  Do you call that a “specific disease?”  It sounds like a pathogen storm to me. This issue complicates cases exponentially and necessitates different medications.  The few minor symptoms they mention are far from the picture of Lyme/MSIDS.  This is probably the most complex illness known to man.
  5. The percentages given for the EM rash are highly inflated.  In the first ever patient sample in Lyme, Connecticut only a quarter had the rash 1976circularletterpdf.  Then there’s this, showing a wide range (27-80%) depending on who’s counting:  https://www.lymedisease.org/lymepolicywonk-how-many-of-those-with-lyme-disease-have-the-rash-estimates-range-from-27-80-2/.  I hardly call that completed and accepted science, yet they throw that number out ALL the time as if Moses etched it on stone tablets.
  6. While everyone claims Lyme is “easily treated” with common antibiotics, I’m concerned the CDC’s recommended mono-therapy of doxycycline is setting people up for potential Alzheimer’s, dementia, and other neurological diseases later:  https://madisonarealymesupportgroup.com/2016/06/03/borrelia-hiding-in-worms-causing-chronic-brain-diseases/,  https://madisonarealymesupportgroup.com/2019/03/09/researchers-identify-herpes-1-chlamydia-pneumoniae-several-types-of-spirochaete-as-major-causes-of-alzheimers/.  Until they acknowledge that borrelia is pleomorphic, this fact remains in the dark about the importance of addressing ALL forms of Bb in treatment.  Doxy doesn’t do that.  To demonstrate treatment complexity, please see:  https://madisonarealymesupportgroup.com/2016/02/13/lyme-disease-treatment/
  7. His statement, “But don’t worry: Doctors in Lyme-endemic states are hip to all this,” is completely ignorant.  Lyme/MSIDS is in a desperate state of affairs and until much change occurs, do not head to a mainstream doctor if you become infected.  You need an experienced practitioner trained by ILADS for this:  https://madisonarealymesupportgroup.com/2018/12/15/everything-about-lyme-disease-is-steeped-in-controversy-now-some-doctors-are-too-afraid-to-treat-patients/.  Mainstream doctors will treat you with the antiquated and unscientific guidelines of 21 days of doxycycline, which has been proven over, and over again NOT to work.
  8. The CDC can be “skeptical” all they want, but there are numerous subsets of folks that remain ill:  https://madisonarealymesupportgroup.com/2019/02/25/medical-stalemate-what-causes-continuing-symptoms-after-lyme-treatment/.  Suffice it to say the science remains unsettled but people are suffering.  As to prolonged courses of antibiotics not being effective and causing long-term complications, I would probably be dead without them and I’m sure many, many others would say the same.  https://madisonarealymesupportgroup.com/2017/07/09/idsa-founder-used-potent-iv-antibiotics-for-chronic-lyme/. This IDSA founder from Wisconsin used 6-8 grams of IV antibiotics for 6 weeks and longer if they required it. Interestingly, Dr. Waisbren stated, “Back in the 1950’s, when many of these drugs were first coming out, infectious disease doctors studied and used them widely. We would put children with rheumatic fever on penicillin for twenty years or more to prevent strep throat and it (the penicillin) did not hurt them. https://www.uppitywis.org/blogarticle/making-difference-milwaukee-doctor-chronicles-silent-epidemic. Trust me when I say that nobody in Lymeland wants to be on antibiotics. Treatment is hard, painful, and expensive.  We are on them because despite what the CDC states, they work better than anything else at present, and compared to most other treatments are affordable.

 

 

 

 

 

 

 

 

 

 

 

 

Danish Study Shows Migrating Birds are Spreading Ticks & Their Pathogens – Including Places Without Sustainable Tick Populations

https://www.ncbi.nlm.nih.gov/pubmed/30709658

2019 Jan 24. pii: S1877-959X(18)30126-2. doi: 10.1016/j.ttbdis.2019.01.007. [Epub ahead of print]

Screening for multiple tick-borne pathogens in Ixodes ricinus ticks from birds in Denmark during spring and autumn migration seasons.

Abstract

Presently, it is uncertain to what extent seasonal migrating birds contribute to the introduction of ticks and tick-associated pathogens in Denmark. To quantify this phenomenon, we captured birds during the spring and autumn migration at three field sites in Denmark and screened them for ticks. Bird-derived ticks were identified to tick species and screened for 37 tick-borne pathogens using real-time PCR. Overall, 807 birds, representing 44 bird species, were captured and examined for ticks during the spring (292 birds) and autumn migrations (515 birds). 10.7% of the birds harboured a total of 179 Ixodes ricinus ticks (38 ticks in spring and 141 in the autumn) with a mean infestation intensity of 2.1 ticks per bird. The European robin (Erithacus rubecula), the common blackbird (Turdus merula), and the common redstart (Phoenicurus phoenicurus) had the highest infestation intensities. 60.9% of the ticks were PCR-positive for at least one tick-borne pathogen. Borrelia DNA was found in 36.9% of the ticks. The Borrelia species detected were B. spielmanii (15.1%), B. valaisiana (13.4%), B. garinii (12.3%), B. burgdorferi s.s. (2.2%), B. miyamotoi (1.1%), and B. afzelii (0.6%). In addition, 10.6% and 1.7% of the samples were PCR-positive for spotted fever group rickettsiae and Candidatus Neoehrlichia mikurensis.

All of the tick-borne pathogens that we found in the present study are known to occur in Danish forest populations of I. ricinus. Our study indicates that migrating birds can transport ticks and their pathogens from neighboring countries to Denmark including sites in Denmark without a sustainable tick population. Thus, a tick-borne pathogen affecting human or animal health emerging at one location in Europe can rapidly be introduced to other countries by migrating birds. These movements are beyond national veterinary control. The current globalization, climatic and environmental changes affect the potential for introduction and establishment of ticks and tick-borne pathogens in Northern Europe. It is therefore important to quantify the risk for rapid spread and long distance exchange of tick-borne pathogens in Europe.

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**Comment** 

Great study until the end.  They have to mention “climatic” changes when this has been proven to be a red-herring:  https://madisonarealymesupportgroup.com/2018/08/13/study-shows-lyme-not-propelled-by-climate-change/

https://madisonarealymesupportgroup.com/2018/11/07/ticks-on-the-move-due-to-migrating-birds-and-photoperiod-not-climate-change/

Ticks are marvelous ecoadaptors and will survive harsh weather by seeking out leaf litter and snow.  In fact, warm winters have proven to be lethal to deer ticks.  In addition to that, please see links above for details on the shoddy science behind the climate model regarding ticks.

And, most importantly, as patients we must continue to insist on tax dollars and monies going for good, solid, transparent research on issues that will relieve human/animal suffering.  

Climate change data has not and will not help patients one iota.

 

Seroprevalence of Bb, Bm, & Powassan in Residents Bitten by Ixodes Ticks

https://wwwnc.cdc.gov/eid/article/25/4/18-0202_article?fbclid=IwAR3Ul329rua5cLKPHHxRVaGsmiH22QIWqjngZyYPO5MJgucoBHdTjjkHFLM

Volume 25, Number 4—April 2019

Seroprevalence of Borrelia burgdorferi, B. miyamotoi, and Powassan Virus in Residents Bitten by Ixodes Ticks, Maine, USA

Robert P. Smith, Susan P. EliasComments to Author , Catherine E. Cavanaugh, Charles B. Lubelczyk, Eleanor H. Lacombe, Janna Brancato, Hester Doyle, Peter W. Rand, Gregory D. Ebel, and Peter J. Krause
_____________________________________________
Reports of Lyme disease in Maine, USA, have increased from a few cases in the late 1980s to 1,848 cases in 2017 (1), coinciding with range expansion of Ixodes scapularis ticks over the past 3 decades (2). The Maine Center for Disease Control reported the first 2 cases of hard-tick relapsing fever caused by Borrelia miyamotoi during 2016 and an additional 6 cases during 2017 (1). Hard-tick relapsing fever might be present as a nonspecific febrile illness (3,4). Han et al. (5) found a B. miyamotoi infection prevalence of 3.7% in adult I. scapularis ticks in Maine, ≈10-fold less than that for B. burgdorferi infection (50%, range 32%–65%) (6).

Powassan virus (POWV) encephalitis can be a devastating human infection and has infected 10 residents of Maine during 2000–2017. There are 2 variants of POWV with distinct enzootic cycles and tick vectors. Lineage 1 is transmitted by I. cookei ticks and lineage 2, sometimes referred to as deer tick virus, is transmitted by I. scapularis ticks (7). Both lineages are present in Maine (7), but lineage 1 has a lesser risk for transmission because human bites by I. cookei ticks are infrequent (8). One fatal Maine case was demonstrated to be caused by lineage 2 POWV (7). Although POWV infection prevalence in Maine I. scapularis ticks is low (0.7%–1.8%) (9), frequent exposure to I. scapularis bites (8) and rapidity of POWV transmission (i.e., POWV might be transmitted to vertebrates after only 15 min from onset of the tick bite) (10) raise concern.

To clarify frequency of exposure to B. burgdoferi, B. miyamotoi, and POWV pathogens, our objective was to determine the seroprevalence of each of these pathogens in residents of Maine, USA, who had been bitten by I. scapularis or I. cookei ticks. We also anticipated that a serosurvey might provide evidence of asymptomatic POWV infection or self-limited illness in a few persons, as reported elsewhere (11,12).

The Study

The Vector-Borne Disease Laboratory of the Maine Medical Center Research provided a free, statewide tick identification service during 1989–2013 to monitor exposure to I. scapularis ticks during range expansion of this invasive vector of human and animal disease. Persons submitted ticks that they had removed from themselves, family members, and pets. As of 2014, 33,332 ticks representing 14 species were identified in Maine; I. scapularis ticks were predominant.

During 2014 (2), we used our tick identification service database to identify persons who had removed >1 attached I. scapularis or I. cookei tick(s) from any person in the household in the previous 5 years (2009–2013). We invited these persons to participate in a serosurvey to assess past exposure to B. burgdorferi, B. miyamotoi and POWV. At the clinics, accompanying family members who self-reported as being tick-bitten were also invited to participate. The study was approved by Maine Medical Center Institutional Review Board (Protocol #4222). Participants provided informed consent (assent for minors) and submitted 30 mL of blood. Blood was centrifuged at 3,500 rpm for 15 min. Serum aliquots were stored at −20°C and then shipped to testing laboratories.

Serologic testing for antibodies to B. miyamotoi was conducted at the laboratory of one of the authors (P.J.K.). An ELISA and confirmatory Western blot assay were used to detect serum reactivity to B. miyamotoi GlpQ protein (13). For the ELISA, serum samples were diluted 1:320 and a signal >3 SD above the mean of 3 B. miyamotoi–negative serum controls was considered positive for B. miyamotoi antibody. Serum samples were considered B. miyamotoi seropositive if ELISA IgG and Western blot IgG tests yielded positive results.

Serologic evidence of exposure to B. burgdorferi was detected by the standard 2-step ELISA and Western blot assay in the Lyme Disease Serology Laboratory at Yale New Haven Hospital by one of the authors (H.D.). A reactive serum was defined as reaction to a dilution >1:100. All borderline or reactive serum were further characterized by Western blot immunoassay. Specimens were considered positive for B. burgdorferi exposure if the IgG immunoblot contained >5 of the 10 most common B. burgdorferi–associated bands (14).

Serologic testing for POWV was conducted by one of the authors (G.D.E.) by using a plaque-reduction neutralization test (PRNT) and a POWV–West Nile virus (WNV) chimeric virus (POWV–premembrane–envelope [prME]/WNV) assay as described (15). The specificity of the assay was determined by cross-neutralization studies, which demonstrated that antiserum raised against POWV efficiently neutralized chimeric POWV–prME/WNV but not WNV and that antiserum raised against WNV do not neutralize POWV–prME/WNV (15). Use of the chimeric POWV–prME/WNV assay virus enabled PRNT testing to be conducted on African green monkey kidney (Vero) cells according to standard procedures by using a 90% neutralization cutoff to be considered positive (15).

Of 230 enrolled persons, 190 were in our tick identification program database, and 40 were family members (Table 1). Among the 190 persons, 1 tick bite was from an I. cookei nymph, 13% of bites were from I. scapularis nymphs, and 86% of bites were from I. scapularis adult females. Engorgement of ticks ranged from slight (43%) to moderate (38%) to high (18%). Among the study population, 32 (13.9%) were seropositive for B. burgdorferi, 6 (2.6%) were seropositive for B. miyamotoi, and 2 (0.9%) were seropositive for both pathogens (Table 2). The serum of 1 person (0.4%) neutralized POWV at a titer of 1:20 and WNV at a titer of 1:10. We designated this serum as flavivirus positive. This person reported a history of neurologic illness for >1 year and a tick bite within the study year.

Conclusions

Among residents of southern Maine with a history of I. scapularis tick bites, the percentage who were seropositive for B. burgdorferi was 6 times greater than that for B. miyamotoi (13.7% vs. 2.1%) and 30 times greater than the percentage of deer ticks infected with POWV (0.4%). Because our study population consisted of persons bitten by I. scapularis ticks (with engorgement ranging from slight to high), we expected seroprevalence to be greater than that for the general population. The B. burgdorferi seroprevalence of 13.7% in our study population was ≈1.5 times higher than the seroprevalence of 9.4% reported by Krause et al. (13) in healthy residents of southern New England. In contrast, the B. miyamotoi seroprevalence of 2.1% was comparable to the seroprevalence of 3.9% reported by Krause at al. (13).

Of 1,854 cases of infection with Borrelia spp. reported in Maine in 2017, a total of 1,848 were attributed to Lyme disease and only 6 (0.3%) were attributed to B. miyamotoi (1). On the basis of a seroprevalence of ≈2% in this study and that B. miyamotoi might be transmitted by all tick stages, we believe that this disease is underdiagnosed in Maine (5). Our population was identified by history of tick exposure, rather than by symptoms. Our results therefore represent the relative frequency of exposure to these different agents rather than risk for illness.

Although the sensitivity and specificity of the 2-tier antibody assay for B. burgdorferi is better validated than those of the B. miyamotoi and POWV assays, the sensitivity and specificity of these assays are good (1315). Nonetheless, our findings might represent overestimates or underestimates of actual exposure to these agents because of false-positive or false-negative results. These data provide evidence that humans are exposed to B. burgdorferi, B. miyamotoi, and POWV in Maine and help define the prevalence of human infection caused by each of these tickborne pathogens.

References

  1. Maine Center for Disease Control. Reportable infectious diseases in Maine, 2017 summary; 2018. [cited 2018 Sep 18]. https://www.maine.gov/dhhs/mecdc/infectious-disease/epi/publications/#annualreports
  2. Rand  PW, Lacombe  EH, Dearborn  R, Cahill  B, Elias  S, Lubelczyk  CB, et al. Passive surveillance in Maine, an area emergent for tick-borne diseases. J Med Entomol. 2007;44:111829. DOIPubMed
  3. Platonov  AE, Karan  LS, Kolyasnikova  NM, Makhneva  NA, Toporkova  MG, Maleev  VV, et al. Humans infected with relapsing fever spirochete Borrelia miyamotoi, Russia. Emerg Infect Dis. 2011;17:181623. DOIPubMed
  4. Krause  PJ, Fish  D, Narasimhan  S, Barbour  AG. Borrelia miyamotoi infection in nature and in humans. Clin Microbiol Infect. 2015;21:6319. DOIPubMed
  5. Han  S, Lubelczyk  C, Hickling  GJ, Tsao  JI. Transovarial transmission rate and filial infection prevalence of Borrelia miyamotoi from Ixodes scapularis collected from hunter-harvested white-tailed deer. Presented at: International Symposium on Tick-Borne Pathogens and Disease; Vienna, Austria; September 24–26, 2017.
  6. Smith  RP, Elias  SP, Borelli  TJ, Missaghi  B, York  BJ, Kessler  RA, et al. Human babesiosis, 1995–2011, Maine, USA. Emerg Infect Dis. 2014;20:172730. DOIPubMed
  7. Cavanaugh  CE, Muscat  PL, Telford  SR III, Goethert  H, Pendlebury  W, Elias  SP, et al. Fatal deer tick virus infection in Maine. Clin Infect Dis. 2017;65:10436. DOIPubMed
  8. Smith  RP Jr, Lacombe  EH, Rand  PW, Dearborn  R. Diversity of tick species biting humans in an emerging area for Lyme disease. Am J Public Health. 1992;82:669. DOIPubMed
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Veterinarian Warns Ticks Active All Year – Not Just Warmer Months

https://www.localdvm.com/news/i-270/veterinarian-warns-pet-owners-of-ticks-that-can-cause-lyme-disease/1818492884

Dr. Susan Keane says ticks are alive all year round, not just in warmer months

THURMONT, Md. – A Thurmont veterinarian is warning pet-owners of what to look for to make sure your four-legged friend doesn’t become a victim of harmful ticks.

Dr. Susan Keane at the Catoctin Veterinary Clinic says ticks that can spread Lyme disease are alive all year round, not just during the warmer months.

She says your dogs, and even cats can catch the harmful bug while playing in the backyard or through a walk in the woods.

Dr. Keane advises that regular checks through their fur, especially the legs, can help with prevention, but here are some other symptoms to look for.

“Joint pain, fever, lethargy, meaning they’re laying around, not eating, anorexia. Any dog going outside, even in a suburban yard there’s some risk of a field mouse dropping a tick or the white-tail deer that we have in Maryland,” Dr. Keane explained.

In the last 100 tests done in January at the clinic, Dr. Keane says, eight percent tested positive for Lyme disease.

But she adds that treatment is available.

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For More:  https://madisonarealymesupportgroup.com/2016/01/20/polar-vorticks/

https://madisonarealymesupportgroup.com/2019/03/06/mild-winter-days-watch-out-for-ticks/

https://madisonarealymesupportgroup.com/2019/02/19/canadian-tick-expert-think-winter-means-no-more-ticks-think-again/

https://madisonarealymesupportgroup.com/2018/12/05/deer-ticks-are-surviving-winter-becoming-a-year-round-problem/

https://madisonarealymesupportgroup.com/2018/08/13/study-shows-lyme-not-propelled-by-climate-change/

Mild Winter Days? Watch Out for Ticks

Winter thaws bring out the ticks. Take precautions when heading outdoors on warm winter days to avoid tick bites. Wearing light-colored clothing and tucking pantlegs into socks can help. Credit: Pavla Zakova | Dreamstime.com

We asked disease ecologist Rick Ostfeld if we need to worry about ticks during the winter. His response is below. (TL; DR = yes)

Blacklegged ticks, which transmit the agents of Lyme disease, babesiosis, and anaplasmosis, disappear in winter, right? Well, not entirely. Although human encounters with these ticks are less likely in winter, there are plenty of ticks out in the environment lurking in a state of (almost) suspended animation.

Larval ticks that hatched the prior summer but failed to find an animal host can become dormant and remain on the forest floor in a quiescent state. The same is true of nymphal ticks, which are normally most active in spring and early summer. These two stages are unlikely to activate until day-length and temperature both increase dramatically. Adult stage ticks, in contrast, most actively seek hosts in the late fall.

The females that were able to engorge on host blood last fall are overwintering in soil pores or under leaf litter, while slowly converting host blood into eggs that they will lay next spring or summer. Some of the adults that did not find a host have died of starvation or other causes, but the unfed survivors will activate any winter or spring day with above-freezing temperatures. In the southern United States, these ticks can be active all year, but even in the northeastern and upper Midwestern regions, ticks can bite during any warmish spell in January, February, and beyond.

As part of The Tick Project, we invite participating households to mail us ticks found embedded in or crawling on people or pets, and we typically receive quite a few even in the coldest months. The riskiest seasons for diseases transmitted by blacklegged ticks are spring and summer, but risk never goes away entirely. And, our 25-years of data from Dutchess County, NY show that, as the climate warms, the ticks come out earlier in the year, advancing the dates of greatest risk.

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For More:  https://madisonarealymesupportgroup.com/2016/01/20/polar-vorticks/   TICK GUY, TOM MATHER, SHOWS HOW TICKS SURVIVE IN 3 DEGREES OVERNIGHT UNDER SNOW COVER.

And regarding all the clamor of “climate change,” independent Canadian tick researcher John Scott has proven it has absolutely nothing to do with tick proliferation and therefore the spread of Lyme/MSIDS:  https://madisonarealymesupportgroup.com/2018/11/07/ticks-on-the-move-due-to-migrating-birds-and-photoperiod-not-climate-change/

https://madisonarealymesupportgroup.com/2018/08/13/study-shows-lyme-not-propelled-by-climate-change/  Warm winters are lethal to I. scapularis (black-legged) ticks.  In fact, overwinter survival dropped to 33% when the snow melted.

So…..when people push the idea that warmer winters somehow make ticks more abundant you can explain with science on your side that –

Warmer winters actually kill ticks