COVID-19
I want to mention that I have seen multiple couples — some that I know personally and some on teh socials — express shock that one half of the couple could test positive while being symptom-free or almost symptom-free while the other got their posterior kicked by COVID-19. Yes, folks, asymptomatic COVID-19 infections are very common. Yes, this is why COVID-19 spreads so widely. Yes, it’s disconcerting. (Yes, this is why I take such careful precautions around everybody except my spouse.)
Long COVID
This paper from UK (2025-09-17) found that people with variant connective tissue had higher risks of Long COVID compared to people without:
- generalized joint hypermobility gave a 29% higher risk of Long COVID;
- extreme hypermobility gave a 112% higher risk of Long COVID.
👦👧 This paper from USA (2025-09-30) reports that a second COVID-19 reinfection in children about doubled the risk of Long COVID compared to children who had had only one COVID-19 infection. In addition, there were added risks for many serious conditions; compared to kids with only one infection, kids with two had greater risks of:
- myocarditis: +260% risk;
- taste/smell dysfunction: +183%;
- thrombophlebitis (inflammation of a vein caused by a blood clot) and thromboembolism (blockage of a vein or artery by a blood clot): +128%;
- heart disease: +96%;
- acute kidney injury: +90%;
- and many others.
💊 This paper from USA (2025-09-25) found that, among adults with depression, the ones who were on SSRIs were only 57% as likely to get Long COVID as the ones who were not on SSRIs. (This is contradicted a bit by this paper (2023-06-08), which found that fluvoxamine (a common SSRI) had no effect on the rate of Long COVID.)
This paper from Sweden (2025-09-30) reports that about a third of Long COVID patients had Postural Orthostatic Tachycardia Syndrome (POTS), versus about 1% in the Swedish population as a whole pre-pandemic. 91% of the Long COVID patients in the study were women.
This paper from USA (2025-10-02) found that being pregnant during a COVID-19 infection did not affect the risk of Long COVID.
Vaccines
💉 This paper from USA (2025-10-08) showed real but modest COVID-19 vaccine effectiveness among US military veterans:
- 29.3% against ER visits;
- 39.2% against hospitalization;
- 64.0% against death.
Almost all of the vaccines were Moderna or Pfizer KP.2 vaccines. Only 0.7% were “other” (probably mostly the Novavax JN.1).
They only broke out data by age for three cohorts, and only for a composite score, which they said was “constructed as the first occurrence of any of the above three outcomes” (which seems kind of odd to me, and which seems like it would weight ER visits heavily). The composite vaccine effectiveness score was:
- 27.7% for people under 65;
- 35.4% for people 65-75;
- 33.5% for people over 75.
Does this low effectiveness mean you shouldn’t bother getting vaccinated? No, for non-elderly people, your biggest risk isn’t hospitalization or death, it’s COVID-related excess sickness and Long COVID, and the risk of those correlates loosely with how bad your acute infection is. Vaccines can lower the risk of damage to your body.
Also, a reminder that the vaccine effectivenesses are calculated relative to people who didn’t get the vaccine but who could have had COVID-19 infections recently. These effectivenesses are going to look worse than the ones we had early on in the pandemic because the controls there had far fewer COVID-19 infections.
💉🤰 This article from USA (2025-10-02) reports that vaccination during pregnancy is a good idea. It was associated with:
- 59% lower risk of maternal COVID-19 infection;
- 25% lower risk of stillbirth;
- 8% lower risk of preterm birth.
Mitigation Measures
😷 This article from USA (2025-10-09) reports that there is a new kind of mask which uses methylene blue to kill pathogens. I don’t know much about it except that it’s available from Amazon in the USA. I might get a box to investigate; I’ll let you know what I find if I do.
Treatments
👃 In my 2025-09-05 post, I shared a paper which said that azelastine nasal spray (a second-generation H1 antihistamine) worked really well as at preventing COVID-19. This blog post (2025-09-24) dissects the paper, and suggests that the paper is not trustworthy. Note that there has been a fair amount of research (see my Treatments page) on the benefits of H1 antihistamines, so I am still going to use it when going into more COVID-dangerous situations.
💊 This paper from USA (2025-09-30) reports that a second, 5-day treatment of Paxlovid for COVID-19 rebound and sped up recovery by about a day. The authors also said, “there was no clear benefit of retreatment because rebound was transient, mild, and did not lead to severe COVID-19.” This frames the benefit only in terms of the direct costs to the healthcare system from the acute illness: no discussion of the benefit to the patient of getting better a day faster, no discussion of the long-term consequences of an infection (i.e. Long COVID or heightened risks of developing other illnesses). While it is true that they didn’t study the long-term consequences, they framed their statement as if long-term consequences didn’t/couldn’t exist. 🙁
Measles
Transmission
According to the Government of Canada Measles and Rubella Monitoring Report (updated 2025-10-06), in the week ending 27 September, the following jurisdictions had the following number of cases:
- Canada: 18;
- Alberta: 7;
- Manitoba: 6;
- BC: 4;
- Ontario: 1.
I’m a bit puzzled by the Ontario case, because this article (2025-10-09) says that Ontario has declared their measles outbreak over because they haven’t seen a new case in 46 days.
Influenza
Vaccines
💉 This review paper (2025-10-03) reports that vaccinating little kids with two influenza vaccines is really really helpful. It’s more helpful the younger the kid is — presumably because their immune system has less experience fighting influenza.
H5N1
Transmission
🧀🐄🐦⬛🤧 This paper (2025-10-08) reports that they found live H5N1 virus in some cheese made with raw milk. They didn’t find any live virus in milk which had been processed to a pH of 5.
Some of their cheese samples were commercial cheese which had accidentally used milk which had H5N1 in it. Some of the cheese samples were made with intentionally spiked milk.
Interestingly, ferrets which ate the contaminated cheese did not get sick. (The ferrets do die if they drink contaminated milk.) They weren’t sure why the ferrets didn’t get sick; one possibility is that the amount of virus in the cheese was lower than in the milk. Another possibility is that the ferrets don’t chew their food much, they just sort of inhale it. That means that the first serious contact with the ferret’s body is in the stomach (which has lots of acid!) and not in the mouth. Maybe the amount of virus on the surface of the cheese isn’t enough to make the ferrets sick.
Alzheimer’s
🧠 This older paper (2023-04-05) reported on links between 22 viruses and later neurological issues. Viral encephalitis and meningitis were particularly bad for later (sometimes much later) diseases. Here are all the studies they found and what the increased multiplier for risk was:
| Virus | Causes | Increased risk (times) |
| meningitis | Alzheimer’s | 62.2 |
| meningitis | Alzheimer’s | 2.8 |
| viral encephalitis, not elsewhere classified/unspecified | Alzheimer’s | 30.7 |
| viral encephalitis, not elsewhere classified/unspecified | Alzheimer’s | 22.1 |
| viral encephalitis, not elsewhere classified/unspecified | Generalized dementia | 40.1 |
| viral encephalitis, not elsewhere classified/unspecified | Generalized dementia | 6.6 |
| all influenza | Generalized dementia | 5.1 |
| all influenza | Generalized dementia | 4.6 |
| all influenza | Parkinson’s | 4.3 |
| all influenza | Parkinson’s | 1.8 |
| all influenza | Vascular dementia | 5.0 |
| all influenza | Vascular dementia | 3.0 |
| all influenza (not pneumonia) | Parkinson’s | 3.7 |
| all influenza (not pneumonia) | Parkinson’s | 2.0 |
| chicken pox/shingles | MS | 3.8 |
| chicken pox/shingles | MS | 2.1 |
| chicken pox/shingles | Vascular dementia | 6.2 |
| chicken pox/shingles | Vascular dementia | 2.3 |
| Epstein-Barr Virus | MS | 26.5 |
| Epstein-Barr Virus | MS | 3.9 |
| herpes simplex | MS | 5.0 |
| herpes simplex | MS | 1.9 |
| influenza (perhaps with pneumonia) | ALS | 7.9 |
| influenza (perhaps with pneumonia) | ALS | 1.8 |
| influenza (perhaps with pneumonia) | Alzheimer’s | 4.1 |
| influenza (perhaps with pneumonia) | Alzheimer’s | 2.6 |
| influenza (perhaps with pneumonia) | Generalized dementia | 6.1 |
| influenza (perhaps with pneumonia) | Generalized dementia | 2.9 |
| influenza (perhaps with pneumonia) | Parkinson’s | 3.0 |
| influenza (perhaps with pneumonia) | Parkinson’s | 1.7 |
| influenza (perhaps with pneumonia) | Vascular dementia | 6.8 |
| influenza (perhaps with pneumonia) | Vascular dementia | 4.6 |
| other viral diseases, not elsewhere classified | Generalized dementia | 3.2 |
| other viral diseases, not elsewhere classified | Generalized dementia | 2.0 |
| viral and other specified intestinal infections | Alzheimer’s | 3.1 |
| viral and other specified intestinal infections | Alzheimer’s | 3.0 |
| viral and other specified intestinal infections | Vascular dementia | 5.3 |
| viral and other specified intestinal infections | Vascular dementia | 2.8 |
| viral hepatitis | Parkinson’s | 2.9 |
| viral hepatitis | Parkinson’s | 2.2 |
| viral infections characterized by skin and mucous membrane lesions | Parkinson’s | 2.5 |
| viral infections characterized by skin and mucous membrane lesions | Parkinson’s | 1.6 |
| viral pneumonia | Generalized dementia | 4.4 |
| viral pneumonia | Generalized dementia | 3.5 |
| viral warts | Generalized dementia | 3.7 |
| viral warts | Generalized dementia | 2.4 |
It’s almost like viruses are bad for you.