Marc Veldhoen
@marcveld.bsky.social
Professor of Immunology 🇳🇱 🇬🇧
Lisbon, 🇵🇹
#Immunology
Time for Science, not silence
https://scholar.google.co.uk/citations?user=7vG1jLIAAAAJ&hl=en
https://orcid.org/0000-0002-1478-9562
threads.net/@marc_veld
mastodon.online/@marc_veld
Lisbon, 🇵🇹
#Immunology
Time for Science, not silence
https://scholar.google.co.uk/citations?user=7vG1jLIAAAAJ&hl=en
https://orcid.org/0000-0002-1478-9562
threads.net/@marc_veld
mastodon.online/@marc_veld
Pinned
Marc Veldhoen
@marcveld.bsky.social
· Nov 29
What will population immunity to SARS-CoV-2 look like in a post-vaccine world?
An updated outlook (2025)
marcveldhoen.substack.com
Five years of COVID taught us one thing: immunology didn’t fail, our public discourse did. My new Substack cuts through the noise with evidence, not ideology. If you want facts over fear, and science over spin, join here:
marcveldhoen.substac...
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marcveldhoen.substac...
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Oh?
Persoonlijke voorkeuren kunnen een rol spelen bij de top voorstellen, niet eerder. Wetenschappers zijn ook mensen, en fashion speelt ook een rol. Maar dat is het. Het is geen utopische voorstelling, maar gewoon hoe het gaat en mijn persoonlijke ervaring al applucant en panel menber.
Persoonlijke voorkeuren kunnen een rol spelen bij de top voorstellen, niet eerder. Wetenschappers zijn ook mensen, en fashion speelt ook een rol. Maar dat is het. Het is geen utopische voorstelling, maar gewoon hoe het gaat en mijn persoonlijke ervaring al applucant en panel menber.
February 11, 2026 at 8:15 AM
Oh?
Persoonlijke voorkeuren kunnen een rol spelen bij de top voorstellen, niet eerder. Wetenschappers zijn ook mensen, en fashion speelt ook een rol. Maar dat is het. Het is geen utopische voorstelling, maar gewoon hoe het gaat en mijn persoonlijke ervaring al applucant en panel menber.
Persoonlijke voorkeuren kunnen een rol spelen bij de top voorstellen, niet eerder. Wetenschappers zijn ook mensen, en fashion speelt ook een rol. Maar dat is het. Het is geen utopische voorstelling, maar gewoon hoe het gaat en mijn persoonlijke ervaring al applucant en panel menber.
The decision by the world’s premier cancer research institute to study ivermectin as a cancer treatment has alarmed career scientists at the agency.
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February 11, 2026 at 8:01 AM
The decision by the world’s premier cancer research institute to study ivermectin as a cancer treatment has alarmed career scientists at the agency.
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If lots of people believe it and it’s moving public health, we as NIH have an obligation, again, to treat it seriously,” Bhattacharya said.
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February 11, 2026 at 8:01 AM
If lots of people believe it and it’s moving public health, we as NIH have an obligation, again, to treat it seriously,” Bhattacharya said.
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Ivermectin has become a symbol of resistance against the medical establishment among MAHA adherents and conservatives.
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February 11, 2026 at 8:01 AM
Ivermectin has become a symbol of resistance against the medical establishment among MAHA adherents and conservatives.
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National Cancer Institute studying ivermectin’s ‘ability to kill cancer cells,’ alarming career scientists
The NCI director didn’t cite new evidence that prompted the agency to look into it
www.statnews.com/202...
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The NCI director didn’t cite new evidence that prompted the agency to look into it
www.statnews.com/202...
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National Cancer Institute studying ivermectin’s ‘ability to kill cancer cells,’ alarming career scientists
The National Cancer Institute is studying ivermectin as a potential cancer treatment, according to its top official, alarming career scientists.
www.statnews.com
February 11, 2026 at 8:01 AM
National Cancer Institute studying ivermectin’s ‘ability to kill cancer cells,’ alarming career scientists
The NCI director didn’t cite new evidence that prompted the agency to look into it
www.statnews.com/202...
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The NCI director didn’t cite new evidence that prompted the agency to look into it
www.statnews.com/202...
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Reposted by Marc Veldhoen
Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
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Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
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February 10, 2026 at 10:42 AM
Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
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Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
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Reposted by Marc Veldhoen
How Scientific Funding Really Works
Why conspiracy narratives about “bought science” collapse under scrutiny
open.substack.com/pu...
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Why conspiracy narratives about “bought science” collapse under scrutiny
open.substack.com/pu...
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How Scientific Funding Really Works
Why conspiracy narratives about “bought science” collapse under scrutiny
open.substack.com
January 31, 2026 at 7:36 PM
How Scientific Funding Really Works
Why conspiracy narratives about “bought science” collapse under scrutiny
open.substack.com/pu...
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Why conspiracy narratives about “bought science” collapse under scrutiny
open.substack.com/pu...
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Reposted by Marc Veldhoen
This is "scaryfying" scientific findings.
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
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Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
February 10, 2026 at 11:37 PM
This is "scaryfying" scientific findings.
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
An average season.
February 10, 2026 at 11:39 PM
An average season.
This does not exclude that inflammation acting on the ChP and brain may be contributing for some LC symptoms, such as sleepiness/desturbed sleep patterns, and that at older age, inflammation does contribute to AD risk. These are seperate issues and not SC2-specific.
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February 10, 2026 at 11:38 PM
This does not exclude that inflammation acting on the ChP and brain may be contributing for some LC symptoms, such as sleepiness/desturbed sleep patterns, and that at older age, inflammation does contribute to AD risk. These are seperate issues and not SC2-specific.
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AD is also involves inflammation.
The authors write "ChP enlargement has long been reported in normal aging" and "ChP is particularly responsive to inflammatory and related stimuli in the ChP microenvironment". Hence this is seen upon and after an infection.
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The authors write "ChP enlargement has long been reported in normal aging" and "ChP is particularly responsive to inflammatory and related stimuli in the ChP microenvironment". Hence this is seen upon and after an infection.
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February 10, 2026 at 11:38 PM
AD is also involves inflammation.
The authors write "ChP enlargement has long been reported in normal aging" and "ChP is particularly responsive to inflammatory and related stimuli in the ChP microenvironment". Hence this is seen upon and after an infection.
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The authors write "ChP enlargement has long been reported in normal aging" and "ChP is particularly responsive to inflammatory and related stimuli in the ChP microenvironment". Hence this is seen upon and after an infection.
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Again, this needs to be emphasised: that certain observations are made or factors or gene products are also involved in other pathological conditions, does not mean the observation is the same or will result in those pathological conditions. They are correlates at best;
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February 10, 2026 at 11:38 PM
Again, this needs to be emphasised: that certain observations are made or factors or gene products are also involved in other pathological conditions, does not mean the observation is the same or will result in those pathological conditions. They are correlates at best;
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There is a very large spread in the LC patients, some may explain the statistical differeence found. LC patients show increased immune activation (unkown why), which will be reflected in many organs participating, inlcuding the brain.
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February 10, 2026 at 11:38 PM
There is a very large spread in the LC patients, some may explain the statistical differeence found. LC patients show increased immune activation (unkown why), which will be reflected in many organs participating, inlcuding the brain.
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LC was defined as SC2+ test, 3 months prior and "neurological complaints temporally related to the SARS-CoV-2 infection." in aq hospital setting. There is a difference in blood flow, not between LC and recovered. There is a increase in volume in LC compared to recovered.
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February 10, 2026 at 11:38 PM
LC was defined as SC2+ test, 3 months prior and "neurological complaints temporally related to the SARS-CoV-2 infection." in aq hospital setting. There is a difference in blood flow, not between LC and recovered. There is a increase in volume in LC compared to recovered.
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The authors don´t help. The conclusion that "These findings suggest that ChP differences in long COVID are associated with AD-related cognitive decline" is way too strong and not justofied. It is a scary conclusion to draw attention, but it does not hold.
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February 10, 2026 at 11:38 PM
The authors don´t help. The conclusion that "These findings suggest that ChP differences in long COVID are associated with AD-related cognitive decline" is way too strong and not justofied. It is a scary conclusion to draw attention, but it does not hold.
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Humans are very diferent from each other and how they respond biologically. The study included 86 long COVID, 67 recovered COVID, patients and only 26 SC2-negative healthy controls. This is a very small study to draw strong conclusions from. The WP title is not justified.
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February 10, 2026 at 11:38 PM
Humans are very diferent from each other and how they respond biologically. The study included 86 long COVID, 67 recovered COVID, patients and only 26 SC2-negative healthy controls. This is a very small study to draw strong conclusions from. The WP title is not justified.
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The study looked at changes in a brain region, the physiological consequences unclear. That it is involved during inflammation and also in neurodegenerative diaease can be two different issues. Inflammation seems the shared item here. There is no infection control.
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February 10, 2026 at 11:38 PM
The study looked at changes in a brain region, the physiological consequences unclear. That it is involved during inflammation and also in neurodegenerative diaease can be two different issues. Inflammation seems the shared item here. There is no infection control.
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Always check the study itself and have it explained by a science litirate and subject knowledgable person. The WP did provide the link, which is great.
alz-journals.onlinel...
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alz-journals.onlinel...
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February 10, 2026 at 11:38 PM
Always check the study itself and have it explained by a science litirate and subject knowledgable person. The WP did provide the link, which is great.
alz-journals.onlinel...
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alz-journals.onlinel...
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This is "scaryfying" scientific findings.
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
February 10, 2026 at 11:37 PM
This is "scaryfying" scientific findings.
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
Okay, this is the WP, you shouldn´t get your news from there.
"May" does an incredible amount of work here. Many things "may" and "can".
There is some data in this, mixed with hype.
1/10
Yes. In the UK, there were 2 visitors from China end of January 2020 who were isolated and the first official cases. February 28th was the first human-to-human reported case in the UK, and then it started spreading.
February 10, 2026 at 11:04 PM
Yes. In the UK, there were 2 visitors from China end of January 2020 who were isolated and the first official cases. February 28th was the first human-to-human reported case in the UK, and then it started spreading.
The graph is indeed correct, the trend started in 2019. Hence, that is not SARS-CoV-2. The very first few infections started in March 2020 in the UK. Those few first infections in one month cannot explain the increase in absent days.
February 10, 2026 at 10:40 PM
The graph is indeed correct, the trend started in 2019. Hence, that is not SARS-CoV-2. The very first few infections started in March 2020 in the UK. Those few first infections in one month cannot explain the increase in absent days.
Did the pandemic have an impact? Certainly, it was a scary period, uncertainty, staying at home more, different life/work situation, loosing people, being worried, etc.
Is the effect due to SC2 infections? In 2020-2022 yes, there were infections without immune memory; illness. But not now anymore.
Is the effect due to SC2 infections? In 2020-2022 yes, there were infections without immune memory; illness. But not now anymore.
February 10, 2026 at 10:37 PM
Did the pandemic have an impact? Certainly, it was a scary period, uncertainty, staying at home more, different life/work situation, loosing people, being worried, etc.
Is the effect due to SC2 infections? In 2020-2022 yes, there were infections without immune memory; illness. But not now anymore.
Is the effect due to SC2 infections? In 2020-2022 yes, there were infections without immune memory; illness. But not now anymore.
It is indeed clear the trend started before the pandemic. The pandemic caused a trend-break, and then it continued. This is more noticable under older workers, and the main loss of days given is mental health.
Blaming all on COVID would be inappropriate.
Blaming all on COVID would be inappropriate.
February 10, 2026 at 10:37 PM
It is indeed clear the trend started before the pandemic. The pandemic caused a trend-break, and then it continued. This is more noticable under older workers, and the main loss of days given is mental health.
Blaming all on COVID would be inappropriate.
Blaming all on COVID would be inappropriate.
Strange that COVID-19 arrived in April 2019, not?
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
February 10, 2026 at 9:51 PM
Strange that COVID-19 arrived in April 2019, not?
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
Reposted by Marc Veldhoen
Science does not claim moral purity. It claims something more robust: procedures that work despite human imperfection. Those procedures are visible, documented, boring and unglamorous. Which is apparently why conspiracy narratives must make them sound sinister.
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January 31, 2026 at 7:35 PM
Science does not claim moral purity. It claims something more robust: procedures that work despite human imperfection. Those procedures are visible, documented, boring and unglamorous. Which is apparently why conspiracy narratives must make them sound sinister.
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