Has there been any research into other coronaviruses and ME?

[LarsSG]

We now know that SARS-CoV-1, SARS-CoV-2 and MERS all cause ME-like post-acute conditions in a significant portion of those infected, even those with very mild or asymptomatic infections. Since these are all coronaviruses, specifically betacoronaviruses, has there been any research into other coronaviruses as a potential cause or trigger for ME? Or any research into post-acute symptoms in general after infection with other coronaviruses? Nothing comes up in my searches.

Top of the suspect list would have to be the other common betacoronaviruses, OC43 and HKU1, both of which are responsible for a small percentage of respiratory infections (somewhere from 1-15% in different studies). I don't think respiratory infections are thought to be a common trigger or cause of ME, so that's a point against, but it is also possible that many infections are very mild or asymptomatic, so I don't think we should discount coronaviruses on that point alone. Sore throat does seem to be quite common in ME. Delayed onset of ME after infection may also be a factor that makes the connection less clear.

Ideally, you'd PCR test a large cohort of people regularly (similar to the ONS infection survey), looking for any number of coronaviruses infections and then follow up with them for six months or so post-infection to see if any of them develop ME or other post-acute symptoms, but that would be a major project.

From the other side, you could take a cohort of pre-pandemic, but recent infectious onset ME patients and compare them to healthy controls, looking for spike and other antigens, antibodies, and perhaps even viral RNA (but I imagine cross-reactivity with SARS-Cov-2 and other coronaviruses, plus how common these coronaviruses are, would make these difficult).

Is there any specific reason to believe that the three pandemic betacoronaviruses are unique in causing post-acute conditions relative to other betacoronaviruses or coronaviruses in general? Certainly other coronaviruses must be less likely to cause long-term post-acute conditions, but that wouldn't be a surprise given the partial immunity that we build up against these other coronaviruses when we are infected as young children (when post-acute conditions are much less common). That could make coronavirus infections less likely to cause post-acute conditions or perhaps limit them to those who by chance weren't exposed to the relevant virus as a child or for whatever reason didn't develop immune memory.

I doubt non-SARS coronavirus infections are responsible for all ME cases, but could they be part of the story?

 

[MeSci]

Is there any specific reason to believe that the three pandemic betacoronaviruses are unique in causing post-acute conditions relative to other betacoronaviruses or coronaviruses in general? Certainly other coronaviruses must be less likely to cause long-term post-acute conditions, but that wouldn't be a surprise given the partial immunity that we build up against these other coronaviruses when we are infected as young children (when post-acute conditions are much less common). That could make coronavirus infections less likely to cause post-acute conditions or perhaps limit them to those who by chance weren't exposed to the relevant virus as a child or for whatever reason didn't develop immune memory.

I doubt non-SARS coronavirus infections are responsible for all ME cases, but could they be part of the story?

I'm not thinking very clearly, and can't take in your whole message, but could ME arise from a symptomless coronavirus infection? Or from one mild enough to cause no obvious infection?

I had a strange illness on the day that I moved to Cornwall in 1984 (11 years before obvious ME) - I had a respiratory illness that made me keep having to stop talking to catch my breath. A few years later I developed sensitivity to perfumes. It was a few years after that that I developed obvious ME.

 

[Trish]

Another version that seems to be suggested is that ME isn't caused directly by whatever the assumed triggering infection, but by reactivation of dormant infection such as EBV.

 

[Peter T]

A problem linking viruses to the triggering of ME is getting sufficient numbers of relevant people to test and knowing what viruses to test for.

An epidemic and/or a pandemic gives a focused opportunity; we know which virus to look at and have lots of people to test.

With EBV in general it is both common and widely tested for, so it is more likely be picked up in people already diagnosed with ME. Also it makes it feasible to test some entire populations, eg the work looking at students cohorts prospectively, identifying how many get the virus and how many subsequently develop ME.

Otherwise in general practice not that many viruses are routinely investigated for. Are we yet at the point that everyone developing ME can be retrospectively screened for all viruses or whole populations prospectively so screened and followed up over some years?

(Note. I can only be specific in saying that I have had EBV based on test results, though I presume I have had a good number of other viruses. Indeed it is probable I have had various influenza infections and that I have had rubella as I had the symptoms of German measles as a child, though the specific viruses have never been formally confirmed. I don’t know how many virus I can say that I have not been infected by based on my medical records, but I suspect not many. I am only aware of a very few that I tested negatively for.

For me the reactivation of EBV by a subsequent virus is an interesting issue, given my initial onset was associated with glandular fever (mononucleosis) and I believed I had recovered after some five years. But then a major ongoing relapse was triggered by what was assumed to be a bad dose of influenza.)

 

[NelliePledge]

Regular laryngitis over 3/4 years was the thing that seemed to mark the noticeable ( in retrospect) start of my gradual onset ME But laryngitis can be caused by a range of common viruses including rhino, adeno, corona, flu and so on. On one occasion gp thought I had mumps again but the test kit got lost in the post do I never took it. Unless testing for viruses becomes cheap enough to be done routinely it will be hard to pin down.

 

[Wyva]

Otherwise in general practice not that many viruses are routinely investigated for. Are we yet at the point that everyone developing ME can be retrospectively screened for all viruses or whole populations prospectively so screened and followed up over some years?

(Note. I can only be specific in saying that I have had EBV based on test results, though I presume I have had a good number of other viruses. Indeed it is probable I have had various influenza infections and that I have had rubella as I had the symptoms of German measles as a child, though the specific viruses have never been formally confirmed. I don’t know how many virus I can say that I have not been infected by based on my medical records, but I suspect not many. I am only aware of a very few that I tested negatively for.

Recently, since I've been getting worse, my GP decided to test me for a range of different viruses (for example several different herpesviruses, hepatitis viruses), just to exclude some sort of weird acute infection. (And I was also retested for EBV, which was my trigger.)

Well, a lot of the results were positive for past infection and my doc remarked when checking the list: "Hm, it looks like you've done a great job at collecting almost every virus through the years..."

I don't remember having any of these, they must have been asymptomatic. Only EBV knocked me out.

(Before EBV I had two serious influenza infections in my life, involving significant weight loss and me becoming weaker for a short while as a result. Those caused me zero post-viral syndromes though. One happened only two years before the EBV-triggered one.)

 

[Mithriel]

I have never had a positive test for EBV.

 

[jenny42]

I recently got given a long covid diagnosis from my Neurologist after 18 years under Neurology trying to get a diagnosis. I never got recent covid and knew what caused my symptoms was probably after a chest infection. It was the time of SARS-1 but as we had so few cases here I don't know if it was that or a different coronavirus as I regularly got chest infections.