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Posted by gmays 19 hours ago

At-home test for infected ticks could improve Lyme Disease diagnosis(www.smithsonianmag.com)
254 points | 92 comments
lima 16 hours ago|
Unfortunately, there are major issues with this approach.

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.

don_esteban 1 hour ago||
Yeah, I would be vary of accuracy of such tests.

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.

lukan 11 hours ago|||
"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."

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/

tito 5 hours ago|||
It's been 15 years since I worked on open source PCR machines, but has someone not figured out how to build a "one time use" disposable type qPCR test? A single test, not an instrument. There's no way these types of tests should be left up to lateral flow etc.
lima 13 minutes ago||
Lucira did that, but IMO it's quite wasteful. LAMP reactions don't need much, so it's best to make a cheap reader like Metrix or Pluslife so the tests can be less expensive.
margalabargala 15 hours ago|||
> The vendor claims "lab-level accuracy" (conveniently omitting the actual accuracy numbers)

Hey, labs have QC failures all the time.

layla5alive 15 hours ago||
The standard isn't to avoid antibiotics until symptoms occur. The standard for a sufficiently attached deer tick in a high risk area is PEP:

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.

lima 15 hours ago||
CDC recommends prophylaxis only if the tick is engorged. In my country, guidelines do not recommend prophylaxis at all (for better or worse - personally, I would take a single doxycyclin dose for a >24h high-risk tick bite, Lyme is no joke).

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?

hammock 14 hours ago||
CDC recommendation is more interested in preventing antibiotic resistance than in preventing Lyme disease for the patient. Obey CDC at your own risk
lima 11 hours ago||
Antibiotics aren't free of risks to the patient either, including doxycycline. There's always a risk tradeoff.
hammock 7 hours ago||
100%. CDC is not a replacement for a trusted doctor
dofm 17 hours ago||
Wow, this seems a pretty big deal.

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.

afavour 17 hours ago||
I have a friend who got a tick bite on holiday in America many years ago. Turns out they got Lyme disease but no doctors in the UK were experienced with it so they dealt with years of misdiagnosis. I really hope any education effort can get out ahead of that.
dofm 17 hours ago|||
Yeah. I think we simply did not see it enough and to be honest far too few doctors ask the "have you travelled" question about unusual disease. It is better now, but I think the "could it be?" thought doesn't occur because the incidence has been low.

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.

KellyCriterion 16 hours ago||||
Thats interesting, since there is a lot of research around face palsy & recovery in UK.
_puk 16 hours ago||
Yep.

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.

KellyCriterion 14 hours ago||
May I ask: Did the muscles on the side of the face with the affection also restore or does she have an muscle-atrophy until today on that side?
throw93949990 14 hours ago|||
Publicly founded health systems are terrible whe. dealing with Lyme disease. It is impossible to simply and clearly diagnose, and separate ill people from "simulants". Something like "back pain" ormother chronic illnesses.
dofm 11 hours ago||
Nothing really to do with public healthcare. It is literally that there is almost no medical or social experience in the UK of actually seeing developed Lyme disease up close, because it has historically been so unusual, so there are no protocols.

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.

nephihaha 19 minutes ago||
1986 is forty years ago. We have Lymes disease in Scotland (I know someone who has it), and a large deer population which has not been properly controlled with substantial remote areas. (Much smaller than the USA but big enough to be reservoirs for the disease.)
nephihaha 22 minutes ago|||
Ticks are much more common in Scotland thanks to deer population and high rainfall. Ticks prefer damp conditions to drought conditions, so this last summer wouldn't have been good for them. The damp makes it easier to survive while they are waiting for passing hosts. They also like long grass and overgrown areas.

England in comparison is much more built up.

We do have Lyme disease here unfortunately. I know someone who has it.

balderdash 7 hours ago|||
One thing pointing out is that deer aren’t really the disease reservoir for Lyme disease (it’s primarily mice) - but deer are key for tick population growth.
dofm 29 minutes ago||
Mice and voles, yes.

(There are more voles in the UK than mice, as it goes. Outnumber them by about thirty million or something. Fairly recently acquired trivia for me, but it turns out that if you see a mouse scurrying in the wild in the UK, away from houses, it's a bit more likely to actually be a vole.)

CalRobert 17 hours ago|||
Certainly had to convince my gp a few years ago that indeed there is Lyme in Ireland
nephihaha 15 hours ago||
It certainly exists in Scotland. Wouldn't surprise me if it got there.
dyauspitr 8 hours ago|||
It started around Connecticut in the 70s and has been spreading out radially since then. I believe it’s still not a huge problem in the western United States (there are other tick borne diseases there however). Soon it will spread across the world and tick bites will be serious business everywhere.
CGMthrowaway 7 hours ago||
Correct. The outbreak was first recognized in 1975 in Old Lyme, Connecticut, directly across the Long Island Sound from the Plum Island Animal Disease Center (a lab which had been doing explicitly offensive biological weapons research until at least 1969), which led to an unverified theory about an escaped bioweapon.

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.

jtfrench 6 hours ago||
I live near Plum Island. Just look at the Google Map reviews to get an idea of the sentiment. Camp Hero, Plum Island…lotta material for Netflix series coming out of Long Island.
throw93949990 14 hours ago|||
Maybe it is a raise of dog ownership in UK as well. They bring ticks inside houee, and shed it in public parks. Our dog used to have like 50 ticks everytime it returned from run.
dofm 11 hours ago||
People are more aware of ticks because of dog ownership, I think, but I don't know if this is a real risk because of the widespread use of tick repellent treatments for dogs (which are their own little eco-disaster).

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.

CGMthrowaway 17 hours ago|||
[flagged]
bhk 6 hours ago||
Ah, yes, climate change, which also explains how Lyme disease, first diagnosed in the US in the northern midwest and northeast, later spread southward. I'm sure it works in mysterious ways in your neighborhood as well.
ElijahLynn 11 hours ago||
Buried way way down:

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.

algoth1 11 hours ago||
There are MANY facebook groups filled with people fully convinced that they have Lyme disease. These groups teach that virtually any and every symptom is caused by the infection and that basically everyone has it. As if this wasn’t insane enough, the people in the group will push each other to go on antibiotics - via so called lyme literate doctors - until they are on the verge of death due to the side effects. Worse: if a lab test is negative they say you should treat by symptom (referring people back to the massive list of virtually every known symptom as proof that they have lyme). It gets worse: even if you get really bad reactions to the treatment, they say you are having a herxheimer reaction and to keep pushing. It gets worse: having followed many of those groups for years, it’s rare that anyone actually gets better from whatever symptom they were having that led them down the self destructive path of lyme self-diagnosis. Well, it actually is a bit worse: even if by some chance you did had a positive lyme test, and if by chance you did got years worth of antibiotics, SOT treatments, etc etc etc… and now you have finally a clean test- well actually it’s bartonella, or parasites, or babesia, or EBV or whatever … so you must carry on. And, it’s not that these people are idiots, it’s just that they fall into a very specific category: 1) have real symptoms, 2) have no real answers from medicine, 3) have internet access, 4) have no notion, not even a tiny spec, of the existence of a concept called falsifiability. So when i read that there’s a new at home test for lyme… on tics(!) i can only imagine the massive amount of suffering this will cause on these poor people… and i imagine many if them will put their blood on the test and come up with all kinds of ways to use this to find yet another proof that they have it
ryandrake 7 hours ago|
We are quickly entering a medical dark age due to the conspiracy theorists, “Do Your Own Research-ers,” YouTube influencers, and other kinds of Internet-borne DIY self diagnosis.
bad_username 2 hours ago||
What didn't help was the response to the pandemic by governments and the scientific establishment, that supplied an unfortunate and pretty devastating blow to public trust in these institutions.
jensensbutton 17 hours ago||
As a parent in the US northeast who likes taking their kids camping and hiking, ticks have been an ongoing conversation this year. I think this is going to sell well.
beej71 16 hours ago|
When I think about moving to the NE from out west, ticks are one of my main reservations. I think, given how many people and dogs recreate out there, I might have it blown out of proportion.
miek 3 hours ago|||
I live in the NE and just picked up Lyme for the second time in 3 years. My child and several friends have had it in the past few years. The problem is that some tick species are unbelievably small and easy to miss. With winters not being as cold, they don't die off as much as they traditionally would. I'd hate to move, but if we keep getting infected, it's not out of the question.
SyneRyder 15 hours ago|||
Not necessarily out of proportion, the Lyme numbers have really spiked there in recent years if you check the official stats.

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.

pimeys 13 hours ago||
Not only Lyme... In the seaside Finland the tick-borne encephalitis cases are going up. And that's no joke either, but at least you get a vaccine for that... if you remember to take it three times before the ticks wake up in springtime.
balderdash 8 hours ago||
A really accurate blood test for tick borne disease would be much more useful that would allow you to know you have something in a time frame you could treat the diseases early.
jambalaya8 14 hours ago||
I saw a commercial for this. I am not sure it makes much sense unless you literally are 100% sure that was the only tick. And it is like I think $40 or $50 a test. I am sure the women I saw discussing the satisfaction they got enjoyed crushing up those little bad guys, and maybe some placebo-like relief, but the truth of the matter is the only really reliable tests for Lyme Disease are blood tests.
vaylian 16 hours ago||
The most interesting part:

> 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

susiecambria 9 hours ago||
If not this, then what?

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.

balderdash 7 hours ago|
Growing up near the epicenter of Lyme disease (which is awful) - it’s not that hard to deal with on a regular basis (I probably take half a dozen plus attached ticks off me year. When your pre-in-post shower - tick check. Take them off, worried they were on for a while, doxycycline as prophylactic. Feel crappy afterwards doctor+blood test / maybe antibiotics. It sucks but it’s manageable. Bourbon virus and alpha gal are super scary. When you k ow about them it’s easier to manage - when you’re oblivious it’s when it’s really dangerous.

What would be way more useful is a quick blood test (pin prick type à la thernos) that could diagnose early for treatment.

PLMUV9A4UP27D 14 hours ago|
I live in Finland, and if I would be following this advice;

> "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.

*https://www.punkkilive.fi/en and https://punkkipankki.fi

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