Research papers on type of onset (infectious, gradual etc)?

I started this thread in part because of a conversation between @Chris Ponting and @Andy about types of onset. I flagged up this thread to Chris, who responded:

He also asked this to be included in the study's log of examples of the benefits of researchers engaging with patients.

Chris wrote a brief summary of the evidence on infectious onset, drawn from the studies discussed here and which I reproduce below, with his permission:

Summary of onset data from studies, based on this thread most show infectious onset in over half of cases:

Chu et al. (2019)

The most common peri-onset events reported by subjects were infection-related episodes (64%), stressful incidents (39%), and exposure to environmental toxins (20%).
DOI: 10.3389/fped.2019.00012 https://www.frontiersin.org/articles/10.3389/fped.2019.00012/full

Fukuda 1994 criteria; 200 participants.


Ghali et al. 2020

ME/CFS precipitants were identifed in 139/197 (70.6%) patients. An infectious event before disease onset was experienced by 97/197 patients (49.2%). Infuenzalike illness was the most frequent infectious precipitants in the 4 groups.
https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-020-02419-4

ME International Consensus Criteria (ME ICC) 2011 criteria; 197 participants


Evans & Jason (2018)

“(93%) from the qualitative sample reported that a virus or infection was the cause of or partial cause of the ME or CFS onset”
https://www.openaccessjournals.com/articles/Onset patterns of chronic fatigue syndrome and myalgic encephalomyelitis.pdf

Self-reported Fukuda; 181 participants



Naess et al. 2010

“Initial infection was reported by 77%.”
https://iv.iiarjournals.org/content/24/2/185.long

Fukuda criteria; 873 people


Salit (1997)

“The symptoms of chronic fatigue initially started in most subjects (96/134, 72%) with an apparent infectious episode”
https://pubmed.ncbi.nlm.nih.gov/9201648/

134 participants; CDC 1988 criteria (Table 2 RIGHT)



De Becker et al. 2002

“almost 60% of the CFS patient group had a potentially infectious etiology” https://www.tandfonline.com/doi/abs/10.1300/J092v10n02_02 (no digital access)

1546 participants


Ray et al. 2007

Infection 93%
https://www.tandfonline.com/doi/abs/10.1080/08870449808406134

60 participants; Oxford definition

Not personally, and the guiding principle of the Decodeme questions is to keep the list to the bare minimum necessary to collect the detail needed for the study itself – in order to reduce the burden on participants. So we won't be expanding the number of questions. There was quite a debate even about asking about glandular fever.

However, I think there is the possibility to ask participants to complete further surveys in future, but that's for another day (and not my decision).

 

This is precisely what happened to me. Had surgery, DVT & PE, hemorrhaging on the anticoagulants, AND gastroenteritis all within two weeks. I have never recovered.

To complicate it further, right around 10 years old I started having frequent flu-like illnesses that caused me to miss at least 20 days of school each year (my sophomore year of high school it was over 50 days). By the time I was in college, I knew I was too sick to manage a full-time job but was unsure what to do about that. I was mild enough that I could still manage going to school full-time but managed it by taking lots of rest days (and in college, nobody is really that bothered if you show up). So...did I have ME/CFS then? I can't say with certainty.

I'm in the process of filling out Solve's survey too and also having a hard time answering the questions based on my onset. While they do ask if you had ill health prior to onset (for years I've been considering onset that ill-fated surgery mentioned above), unfortunately for their data collection, I'm having to answer questions based on sometimes using my experiences from when I was younger, and some post-surgery. It's a mess.

 

This is an important point, especially for people whose onset wasn't clear. I associate mine with EBV because I was definitely exposed to it by my boyfriend, but I didn't begin to develop ME symptoms until five or six months later. This being the 70s, no tests for EBV were done even on the friends who did become ill.

However, it could feasibly have been a gradual process involving several viruses, which took almost 10 years to manifest fully. It started with never quite being the same after measles at age 7; there were several periods of odd symptoms such as burning and twitching muscles, which would then disappear as mysteriously as they'd begun; and there were other viruses that made me more unwell than would usually be expected.

I talk about my ME onset being the point where I began to get symptoms that stayed in a broadly consistent pattern and, unlike the lengthy prodrome, didn't randomly disappear for long periods. But honestly, who knows!

 

I've been thinking about a paper I read and realized I'd dismissed findings like this

Because self-reported onset seemed unreliable. However, with COVID-19 this problem is ameliorated as many, especially later on in the pandemic can verify infection type, severity and mostly the exact timetable from onset to me/cfs symptom profile. Sure, there will still be the question of other triggering events, but less surgeries for example.

I think establishing an onset timetable could be a useful epidemiological (thanks spellcheck) contribution. Btw, interesting both found a gap from infection to symptom onset in about 40% of patients, although the covid paper if of a much lower quality.