At-home test for infected ticks could improve Lyme Disease diagnosis
smithsonianmag.com
smithsonianmag.com
The vendor claims "lab-level accuracy" (conveniently omitting the actual accuracy numbers), but the test is a lateral flow test, which means its Limit of Detection is going to be orders of magnitude worse than molecular tests. Tick tests do not require FDA clearance, so their claims are most likely unreviewed.
Existing lab tests for ticks are almost universally based on PCR.
Ticks are small (especially nymphs) and extracting enough material can be tricky even for molecular testing, so I can't imagine an LFT test working terribly well, especially for nymphs, which are responsible for a lot of Lyme infections due to being easy to miss.
The other, bigger problem is that the test result is mostly useless.
The risk of Lyme transmission from an infected tick ranges rougly from <1% for a fresh bite (<24h) to ~10-25% once the tick is engorged (72h+). A positive tick test result would be insufficiently predictive of Lyme disease transmission on its own to justify taking antibiotics in most cases in the absence of other symptoms.
And you can't trust negative results either due to limited sensitivity, so you can't rule out transmission either.
In my opinion, tests like this can lead to worse overall health outcomes due to unnecessary treatment or withholding prophylaxis from someone who otherwise qualifies.
Lyme post-exposure prophylaxis (PEP) is a single dose of doxycycline (200 mg for adults, or weight-adjusted for children) taken within 72 hours of removing a high-risk blacklegged tick bite to prevent Lyme disease.
However, guidelines universally recommend against testing ticks. For instance, IDSA says this:
> Knowing tick characteristics (ie, species, life stage, and an assessment of the degree of blood engorgement) is helpful for anticipatory guidance and in determining if antibiotic prophylaxis to prevent Lyme disease is appropriate [127]. Tick identification is available in most commercial laboratories and at some local health departments. Studies from the United States and Europe have shown that detecting B. burgdorferi sensu lato in Ixodes spp. ticks, however, poorly predicts either subsequent disease (0–12.4%) [126, 128–133] or asymptomatic seroconversion (0–4.7%) [126, 129, 130, 132, 134]. This is likely due to a variety of factors that influence the likelihood of transmission and the observation that most Ixodes spp. ticks discovered by patients have been attached for <48 hours [61, 62, 135].
(https://www.idsociety.org/practice-guideline/lyme-disease/)
The point is that the test is likely not useful to reliably inform any sort of prophylactic treatment, especially if the risk of transmission is high enough to warrant prophylactic treatment in the first place, in which case the PEP is indicated regardless of the tick test.
Sure, it modifies the prior probabilities, but what's the clinical significance of that?
Hey, labs have QC failures all the time.
Even smaller and less noticeable are the larvae. And I know I learned that they cannot transmit the disease, because they only do so, if they have biten an infected animal before - so I never worried about small ticks, but apparently new research indicates, that this is wrong.
"However, newer research suggests that some pathogens, including Borrelia miyamotoi, may be transmitted from the adult female tick directly to her offspring.
This means larval ticks may already be infected before their first bite."
https://danielcameronmd.com/larval-ticks-borrelia-miyamotoi/
The infected unfed ticks have few spirochetes in them. The numbers grow by two orders of magnitude as they feed - the reason why old bites are much more dangerous than the fresh bites.
Here in the UK, Lyme traditionally been a marginal problem (tick bites aren't) but we now have such rapid climate change, along with rapidly increasing wild deer and boar populations, that some areas in the UK are becoming risk zones on more or less the same level of risk as some US regions.
Alas the difference here is that education has not caught up to the USA: very few people have any grasp of the risk of Lyme because the high risk zones are, by and large, not well known, and they don't always correlate that well with the basic risk of acquiring a tick.
I think most specialists in the UK think this is likely to lead to a pretty big increase to infections before people learn, so maybe this sort of tool will help offset that.
I walk a lot in an area with some wild deer and boar, and I would love to have one of these in my cupboard as a precaution. Would be great to see them in supermarkets in high risk areas, too.
There is a more severe risk around rabies. We basically do not have it in the UK or Ireland; it has been eliminated for over a century except a tiny incidence of a virus in the same family in bats. But because we have essentially eradicated it, doctors do not often think to ask about it, even in people who have travelled, which led to someone suffering awfully last year.
And since a dog bite or even a fox bite in the UK or Ireland carries literally zero risk of rabies, those who are bitten or scratched while travelling abroad do not have it uppermost in their mind.
About 20 years ago my gran got to the facial palsy stage of Lyme's before it was even considered and diagnosed by a visiting locum doctor who'd grown up in another country.
Antibiotics were given, her face recovered (albeit slowly).
It's a horrendous disease.
A few thousand cases every year now, when the first indigenous case ever properly recorded in the UK was only in 1986, and it's not like in the USA where really wide areas are high risk. Some of the pockets of highest risk Lyme in the UK are no more than a few miles across.
Nurse stations and pharmacy clinics are great at properly removing ticks if you know you have been bitten, and from there you will now get good advice about Lyme.
But a system that has no endemic experience of Lyme is just not going to test for it. Because it's remote, and people are usually unaware they have been in risk areas, and often unaware they've even been bitten.
Epidemiologically recent (and also dofm-recent because I'm old).
But the graphs typically show that Scotland ballooned in the last twenty years, from below a hundred a year into the thousands.
Apparently in the UK it is now mostly stable, so it is endemic in deer. Much more common in middle-aged people who are I guess more likely to walk the dog and be keen active gardeners.
The deer thing is annoying. They have been mostly bred as game animals, and yet they aren't treated as game anymore for the most part so their numbers have exploded.
COVID lockdowns changed us and we're a bit more outdoorsy.
But mostly it is the deer population. There are now four times as many wild deer in the UK as there were before the first indigenous case of Lyme was detected. From under half a million to well over two million over that timeframe.
In the south east around where I am, wild boar are now a potentially significant vector in the high risk areas, too — we've gone from literally zero to a couple of thousand wild boar in the same forty-year period of time just in the 20 miles around me. They apparently can carry upwards of a hundred without suffering.
I'm worried that I don't want to know the answer to this, but why?
I use one of the common types on my dogs and that stuff is crazy effective on ticks.
Genetic studies and museum tick specimens prove the bacteria existed in North America for thousands of years before the lab was built. Whether there was gain of function done on it is not publicly verified.
England in comparison is much more built up.
We do have Lyme disease here unfortunately. I know someone who has it.
But weirdly almost all of the peak risk areas for Lyme (and the encephalitis disease) are in the south. This would suggest risk is about deer population density rather than absolute numbers.
So for example the New Forest, Thetford Forest and Exmoor have higher density populations of smaller deer like muntjac and sika.
It appears obviously worse in smaller protected forests that have large deer populations. The risk in Thetford Forest is really high.
LymeAlert, which will sell for about $50, is designed to detect the presence of Borrelia burgdorferi, the pathogen known to cause Lyme disease, in a tick.
The test kit, which remains effective for up to 12 months, is simple to use. After carefully removing the tick with either tweezers or a tick-removal tool, you place it into the kit’s “Tick Crusher.” The grinder pulverizes the tick’s chitinous exterior, exposing the internal contents where the Borrelia burgdorferi is located. A patent-pending buffer solution readies the sample for testing. The user then inserts a test strip into a slot in the grinder. The strip’s chemically treated nitrocellulose paper functions as an immunochromatographic assay that can detect the presence of Borrelia burgdorferi.
I'd written a longer reply about my time last year in upstate NY, but what I wrote was "tinted"... so the shorter version: within just a 2 month stay I did find infected ticks on me (submitted to testing - I was happy with nyticks.org). Everytime the cat came into the house, first step was always to get out the tick mitt and brush off the ticks from the cat. And it felt weird how Lyme was normalised there, almost like a phase of life it's assumed you go through, having to take months off work due to crippling pain and paralysis until the meds work. Coming from Australia, none of this felt "normal".
That said: it's a truly beautiful place. Outdoor recreation seems to be "what you do" out there... but when it's that beautiful, it'd be a shame not to take advantage of it. Even though I'm not much of a nature person or a hiker.
> After carefully removing the tick with either tweezers or a tick-removal tool, you place it into the kit’s “Tick Crusher.” The grinder pulverizes the tick’s chitinous exterior, exposing the internal contents where the Borrelia burgdorferi is located
Like others, I was interested in the article because of Lyme and other diseases. Ticks really do suck.
I appreciate all the science-y comments though I understand very little. I appreciate comments about personal experiences with ticks, getting bitten, and getting sick.
I’m left with this: If this test is not really a viable solution (or at least one solution) to the problem of the unaffordability of visits to the doctor, what is a better solution. I would put all options on the table and move things like universal health care to the “working on it but not helpful right now” pile of solutions.
What would be way more useful is a quick blood test (pin prick type à la thernos) that could diagnose early for treatment.
> "If you have an embedded tick where there’s a chance of infection, then go to your doctor and get a dose of antibiotics as a prophylactic, just to be on the safe side." ...I would be eating antibiotics 5 months per year each year of my life. I've had 13 ticks this summer, and it's the least I've ever had in a summer ever I think. I sometimes go over a 100 on a summer. But I've just had Lyme's disease once confirmed, but before that I had anti-bodies (which I got to know through a research project i participated in).
There's a lot of research on ticks going on in Finland, and I participate in two citizen science projects* this summer; for one I collect the ticks and send them to the researchers, the other project I just post observations.
I quickly realized it was a hassel to submit to both projects every time I found a tick on me or the cats. So I used Claude Code to build my own self-hosted app that stores my profile, location etc and submits my findings to both of the projects. Simple and nice litte project. I have a thought of publishing the app in some form, but haven't thought about it much.
The article also mentions that symptoms sometimes persist after treatment with antibiotics.
Could be a very big deal if it could be made properly inexpensive. COVID tests were, after all.
If you could know as soon as you were bitten whether there was any risk of infection at all, that would be very valuable information.
I think it's only a one in ten chance that an infected tick would transmit the infection, anyway. But you would know whether you needed to even book an appointment.
So one more tool in the toolbox is a very good thing.
Only if the test is sufficiently accurate to rule out transmission. Even molecular tests can't reliably predict that.
As mentioned in the article, this is not a safe way to assess Lyme disease. I still want to know what biohazards these tiny critters hold.
Or actually let's just eradicate all ticks.
(Also, I have the same question about the poison ivy immunotherapy pills that were common in the US before the FDA.)
Unfortunately vaccine-denialists will say 'ah this person died from getting a vaccine, we shouldn't vaccinate anyone'. Even if the vaccine saves millions of lives.
Of course you can just say they didn't investigate it enough or whatever, you aren't trying to make a reasoned argument and thus don't need to exercise reason.
This exact pattern has been playing out with the COVID vaccine and the HPV vaccine. There are communities who are convinced that every medical problem they had since receiving the HPV vaccine is due to the vaccine, even though they’re all having different health problems that also occur in the overall population.
As I said, these are people who went to some effort to try a novel vaccine. If they do that, I think it's unlikely that they are anti-vaxxers. Presumably they'd also know - or would be told - that the vaccine can't be expected to work on any post-Lyme symptoms you already have.
Here is the link for all downvoters :-D
https://news.ycombinator.com/item?id=32465108
(Aug 2022, exactly what I said with "some years ago")
The Pfizer Lyme vaccine is in the Wikipedia article linked that you responded to, and the link there works whilst the link in the story you linked is dead.
Whilst it might be nice to remove some downvote privileges we could apply the rules we do have and not complain about downvotes.
To my view, your original comment was fine, but I could also see others wouldn't like it.
Yes, and thats interesting and allows for sure some question for why getting downvoted, when everything you do is pointing to an article on the same forum to adjacent topic .. and still get a punch :-D
https://pharmaphorum.com/news/pfizer-valneva-lyme-vaccine-st...
This has created an intense fear of Lyme disease among people who don’t trust doctors and “do their own research”. That group overlaps a lot with anti-vax groups. You can see where this is going. Some people who got the Lyme vaccine because they saw it as the lesser of two evils and then subsequently had medical issues blamed everything on the vaccine, and it blew up into lawsuits and a belief that the vaccine causes these problems. If there was any real problem we’ll never know because the storm was such a mess that it made actual research impossible and scared so many people away from the vaccine that it was withdrawn from the market.
I believe in my country this is treated differently...
If you catch it early before it takes hold, the treatment is almost inconsequential. If you delay, it's up to a 4 week course of antibiotics.
Jeez! Chasing ticks, c'mon, really, my f*ing intelligence is insulted by the suggestion.
Similar to rabies, Lyme disease itself slowly disseminates through the flesh over months, by the time it's spread you are very sick.
Used to be a big Event Of The Year when my grandpa found one after spending all day out in their 'garden' (a few acres bordering deep woods). I remember being maybe 11 when he found one, let me try and figure out how to crush it, I couldn't. He showed me how to use the butt of a butterknife and leverage to get the fuckers
I don't live anywhere near a proper forest and we've had several close calls this year, I caught one crawling across my scalp when I was getting into bed last month. Went and got tested just to be safe
I know feeding crows is really fun, but please don't. It's very important that they get hungry enough to eat mice sometimes. Same goes for deer, the past couple of years I've had them walk _towards_ me and my dog instead of bolting, presumably because someone is feeding them (by hand, not garden raiding)
Ticks also get attached to humans in tall grass and forest edges, not from the trees. Walking through open fields is a more likely way to get a tick than walking through the woods, because that is where the deer sleep. They bed down in tall grass, and the ticks come along for the ride. So be wary of the grass, not the woods. As a matter of fact, the best thing you can do to keep ticks away from your home if you live out in the country is to keep 8-10 feet of grass cut really short at the perimeter of your property or wherever it meets the woods.
Young deer often walk towards people, too. They aren't born afraid of humans, and have natural instincts to freeze, not flee. So when their mama hides them, it is just as likely to be near humans, not in the woods with the coyotes. They'll learn the fear soon enough (definitely during hunting season), but until then they certainly have youthful curiosity.
Even so, "sign me up" is still a good answer. Home testing sounds great.
Still feeling cool, suave, experienced, and fearless?
But you can probably tell that there is no need to be snarky. Just your first sentence would have been more in line with how people engage with each other around here.
I have at least one serious regret about trusting someone on the internet saying something incorrect confidently.
My response aims to inhibit and disrupt the complacency neuron of the reader that might have been activated by your comment. Sorry, but learning hurts sometimes.
No need to be rude, though!
Do you kindly and charitably respond to antivaxxers and drug dealers?
You don't respond to them at all, flag the comment, and/or email the moderators.
Being snarky does not contribute to the discussion and gets your comments flagged.
I should respond to bad info by continuing to lurk. Very smart!
You were right to call out the other person for trivializing the risks of tick bites, just assume good faith and be kind.
In the trees they drop down on you from above. Had them do that many times.
The general consensus is to wear a hat when mushrooming in the places I've been.
They have thermal sensors on their forearms and are known to climb trees. Why wouldn't they approach from above?
If you're going to disagree with basic textbook biology knowledge, the burden of proof is on you.
> In contrast to D. variabilis, A. americanum is regarded as a hunter tick, which will walk/crawl rapidly across many meters when attracted by host odors. This behavior enhances its host range since these ticks do not have to wait for a passing host.
You are taking the official, "please don't panic" story from CDC and trying to force it down everyone's throats while claiming it's as basic a fact of biology as chromosomes and the mitochondria. It's not. This is a contested area of animal behavior, not a microscopic process.
Are you persistent in being dense because you want somebody to engage with and correct you, or are you genuinely trying to get people infected?
I definitely agree that without these nightmarish tick conditions it's a non-event, but with them...
They're much, much smaller. The size of a poppy seed.
https://www.cdc.gov/lyme/about/lyme-disease-vaccine.html
Looks like there are clinical trials of a new vaccine, maybe demand will be higher this time around. The link also mentions a PrEP-type of treatment, which would be given seasonally. My bet is on that one, big pharma loves nothing more than a treatment that isn't quite a cure, but requires constant maintenance.