Michael Coston
Editor, Senior Moderator
The Lancet: Vascular and Inflammatory Diseases after COVID-19 Infection and Vaccination in Children and Young People in England
Credit ACIP/CDC
#18,936
Despite ample evidence to the contrary, much of the world seems to have decided that COVID is now a relatively benign seasonal respiratory virus, on par with the common cold or - in severe cases - the flu.
The following is a partial list of studies we've covered over the past 90 days that would beg to differ.
Nature: Viral Infections and the Risk of Neurodegenerative Diseases (Meta-Analysis & Systemic Review)
European Society of Cardiology: Major Consensus Statement Released on Long-Term Cardiovascular Impact of COVID Infection
CSIRO Pub: Impacts of Long COVID on Disability, Function and Quality of Life for Adults Living in Australia
EHJ: Accelerated Vascular Ageing After COVID-19 Infection: The CARTESIAN Study
Preprint: Incidence of Long COVID Following Reinfection with COVID-19
Despite this mountain of evidence, uptake of COVID vaccines has plummeted, mask-wearing has gone decidedly out of fashion, and most people no longer see the need to stay home when symptomatic.
While some people will allow that COVID might be dangerous to older individuals, they continue to insist that the risk for young adults - and particularly children - is minimal.
Today we've a major retrospective cohort study - using national health records for nearly 14 million people under 18 in England - to compare risks of vascular and inflammatory diseases after COVID-19 infection and following BNT162b2 vaccination.
While the risks for younger individuals from COVID is lower, it is not zero.
Vascular and inflammatory diseases after COVID-19 infection and vaccination in children and young people in England: a retrospective, population-based cohort study using linked electronic health records
Alexia Sampri, PhDa,b as3293@medschl.cam.ac.uk ∙ Wen Shi, PhDa,b ∙ Thomas Bolton, PhDc ∙ Samantha Ip, PhDa,b,d,e ∙ Rochelle Knight, MScif,g ∙ Venexia Walker, PhDf,g,i ∙ et al. Show more
Download PDF
Summary
Background
The rarity of severe diseases following COVID-19 infection balanced against rare COVID-19 vaccination-related adverse effects is an important consideration for vaccination policies. We aimed to assess the short-term and long-term risks of vascular and inflammatory diseases following first COVID-19 diagnosis and vaccination in children and young people.
Methods
In this retrospective, population-based cohort study, we analysed whole-population linked electronic health records for all individuals in England aged younger than 18 years, registered with a general practitioner, and with known age, sex, and region of residence, between Jan 1, 2020, and Dec 31, 2022. Outcomes were arterial thrombotic events, venous thrombotic events, thrombocytopenia, myocarditis or pericarditis, and inflammatory conditions. COVID-19 diagnosis was defined as the earliest record of a positive SARS-CoV-2 PCR or antigen test, or a COVID-19 diagnosis code in primary-care or secondary-care records; COVID-19 vaccination was defined as the earliest documented receipt of the BNT162b2 vaccine (the predominant vaccine during the study period). Adjusted hazard ratios (aHRs) for all outcomes were estimated by time since a first COVID-19 diagnosis during Jan 1, 2020–March 31, 2022 and by time since a first COVID-19 vaccination during Aug 6, 2021–Dec 31, 2022, adjusting for age, sex, ethnicity, region, deprivation, general practitioner contact frequency, and medication use.
Findings
Of 13 896 125 individuals younger than 18 years (6 784 260 [48·8%] female and 7 111 865 [51·2%] male; 9 979 420 [71·7%] White), 3 903 410 (28·1%) had a COVID-19 diagnosis. COVID-19 diagnosis (compared with no or before diagnosis) was associated with higher risk of arterial thromboembolism (aHR 2·33 [95% CI 1·20–4·51]), venous thromboembolism (4·90 [3·66–6·55]), thrombocytopenia (3·64 [2·21–6·00]), myocarditis or pericarditis (3·46 [2·06–5·80]), and inflammatory conditions (14·84 [11·01–19·99]) in the first week after diagnosis. Incidence declined in weeks 2–4, but remained elevated to beyond 12 months for venous thromboembolism (1·39 [1·14 –1·69]), thrombocytopenia (1·42 [1·01–2·00]), and myocarditis or pericarditis (1·42 [1·05–1·91]). Among 9 245 395 individuals aged between 5 and younger than 18 years who were eligible for vaccination (4 510 490 [48·8%] female and 4 734 905 [51·2%] male; 6 684 140 [72·3%] White), 3 407 560 (36·9%) received a first vaccine. COVID-19 vaccination (compared with no or before vaccination) was associated with elevated risk of myocarditis or pericarditis within the first 4 weeks after vaccination (1·84 [1·25–2·72]). The 6-month absolute excess risks for myocarditis or pericarditis were 2·24 (1·11–3·80) per 100 000 individuals after diagnosis versus before diagnosis or undiagnosed, and 0·85 (0·07–1·91) after vaccination versus before vaccination or unvaccinated.
Interpretation
Children and young people have higher risks of rare vascular and inflammatory diseases up to 12 months after a first COVID-19 diagnosis and higher risk of rare myocarditis or pericarditis up to 4 weeks after a first BNT162b2 vaccine, although the risk following vaccination is substantially lower than the risk following infection.
These findings are of great importance for national policy makers and caregivers considering vaccination consent for children, and support the public health strategy of COVID-19 vaccination in children and young people to mitigate the more frequent and persistent risks associated with SARS-CoV-2 infection.
Funding
Wellcome Trust, British Heart Foundation Data Science Centre, and Health Data Research UK.
(Continue . . . )
“Our whole-population study during the pandemic showed that although these conditions were rare, children and young people were more likely to experience heart, vascular or inflammatory problems after a COVID-19 infection than after having the vaccine — and the risks after infection lasted much longer.”
The research team uncovered these findings by analysing linked electronic health records (EHRs) for nearly 14 million children in England under the age of 18 between 1 January 2020 and 31 December 2022, covering 98% of this population. During this period, 3.9 million children and young people had a first COVID-19 diagnosis. And 3.4 million had a first COVID-19 BNT162b2 (Pfizer–BioNTech) vaccine, the main vaccine used in 5-18-year-olds during the study period.
(Continue . . . )
While all of this should be highly reassuring to parents considering the COVID vaccine for their kids, the reality is, most people will probably never see it.
It isn't `click-baity' enough for social media, and frankly, it challenges our increasingly laissez-faire post-pandemic public health policies.
But at least its out there, for anyone who cares to read it.
https://afludiary.blogspot.com/2025/11/the-lancet-vascular-and-inflammatory.html
Credit ACIP/CDC
#18,936
Despite ample evidence to the contrary, much of the world seems to have decided that COVID is now a relatively benign seasonal respiratory virus, on par with the common cold or - in severe cases - the flu.
The following is a partial list of studies we've covered over the past 90 days that would beg to differ.
Nature: Viral Infections and the Risk of Neurodegenerative Diseases (Meta-Analysis & Systemic Review)
European Society of Cardiology: Major Consensus Statement Released on Long-Term Cardiovascular Impact of COVID Infection
CSIRO Pub: Impacts of Long COVID on Disability, Function and Quality of Life for Adults Living in Australia
EHJ: Accelerated Vascular Ageing After COVID-19 Infection: The CARTESIAN Study
Preprint: Incidence of Long COVID Following Reinfection with COVID-19
Despite this mountain of evidence, uptake of COVID vaccines has plummeted, mask-wearing has gone decidedly out of fashion, and most people no longer see the need to stay home when symptomatic.
While some people will allow that COVID might be dangerous to older individuals, they continue to insist that the risk for young adults - and particularly children - is minimal.
Today we've a major retrospective cohort study - using national health records for nearly 14 million people under 18 in England - to compare risks of vascular and inflammatory diseases after COVID-19 infection and following BNT162b2 vaccination.
While the risks for younger individuals from COVID is lower, it is not zero.
- This study found that COVID infected children and teens had a small, but higher risk of blood clots, heart inflammation, and rare inflammatory diseases - sometimes lasting up to a year post infection.
- Following vaccination, this study only found a short-term rise in mild heart inflammation. Overall, infection caused more, and longer-lasting problems, than vaccination.
Vascular and inflammatory diseases after COVID-19 infection and vaccination in children and young people in England: a retrospective, population-based cohort study using linked electronic health records
Alexia Sampri, PhDa,b as3293@medschl.cam.ac.uk ∙ Wen Shi, PhDa,b ∙ Thomas Bolton, PhDc ∙ Samantha Ip, PhDa,b,d,e ∙ Rochelle Knight, MScif,g ∙ Venexia Walker, PhDf,g,i ∙ et al. Show more
Download PDF
Summary
Background
The rarity of severe diseases following COVID-19 infection balanced against rare COVID-19 vaccination-related adverse effects is an important consideration for vaccination policies. We aimed to assess the short-term and long-term risks of vascular and inflammatory diseases following first COVID-19 diagnosis and vaccination in children and young people.
Methods
In this retrospective, population-based cohort study, we analysed whole-population linked electronic health records for all individuals in England aged younger than 18 years, registered with a general practitioner, and with known age, sex, and region of residence, between Jan 1, 2020, and Dec 31, 2022. Outcomes were arterial thrombotic events, venous thrombotic events, thrombocytopenia, myocarditis or pericarditis, and inflammatory conditions. COVID-19 diagnosis was defined as the earliest record of a positive SARS-CoV-2 PCR or antigen test, or a COVID-19 diagnosis code in primary-care or secondary-care records; COVID-19 vaccination was defined as the earliest documented receipt of the BNT162b2 vaccine (the predominant vaccine during the study period). Adjusted hazard ratios (aHRs) for all outcomes were estimated by time since a first COVID-19 diagnosis during Jan 1, 2020–March 31, 2022 and by time since a first COVID-19 vaccination during Aug 6, 2021–Dec 31, 2022, adjusting for age, sex, ethnicity, region, deprivation, general practitioner contact frequency, and medication use.
Findings
Of 13 896 125 individuals younger than 18 years (6 784 260 [48·8%] female and 7 111 865 [51·2%] male; 9 979 420 [71·7%] White), 3 903 410 (28·1%) had a COVID-19 diagnosis. COVID-19 diagnosis (compared with no or before diagnosis) was associated with higher risk of arterial thromboembolism (aHR 2·33 [95% CI 1·20–4·51]), venous thromboembolism (4·90 [3·66–6·55]), thrombocytopenia (3·64 [2·21–6·00]), myocarditis or pericarditis (3·46 [2·06–5·80]), and inflammatory conditions (14·84 [11·01–19·99]) in the first week after diagnosis. Incidence declined in weeks 2–4, but remained elevated to beyond 12 months for venous thromboembolism (1·39 [1·14 –1·69]), thrombocytopenia (1·42 [1·01–2·00]), and myocarditis or pericarditis (1·42 [1·05–1·91]). Among 9 245 395 individuals aged between 5 and younger than 18 years who were eligible for vaccination (4 510 490 [48·8%] female and 4 734 905 [51·2%] male; 6 684 140 [72·3%] White), 3 407 560 (36·9%) received a first vaccine. COVID-19 vaccination (compared with no or before vaccination) was associated with elevated risk of myocarditis or pericarditis within the first 4 weeks after vaccination (1·84 [1·25–2·72]). The 6-month absolute excess risks for myocarditis or pericarditis were 2·24 (1·11–3·80) per 100 000 individuals after diagnosis versus before diagnosis or undiagnosed, and 0·85 (0·07–1·91) after vaccination versus before vaccination or unvaccinated.
Interpretation
Children and young people have higher risks of rare vascular and inflammatory diseases up to 12 months after a first COVID-19 diagnosis and higher risk of rare myocarditis or pericarditis up to 4 weeks after a first BNT162b2 vaccine, although the risk following vaccination is substantially lower than the risk following infection.
These findings are of great importance for national policy makers and caregivers considering vaccination consent for children, and support the public health strategy of COVID-19 vaccination in children and young people to mitigate the more frequent and persistent risks associated with SARS-CoV-2 infection.
Funding
Wellcome Trust, British Heart Foundation Data Science Centre, and Health Data Research UK.
(Continue . . . )
Health Data Research UK news release
The study is the largest of its kind in this population, and is published in The Lancet Child and Adolescent Health. It was led by scientists at the Universities of Cambridge and Edinburgh, and University College London, with support from the BHF Data Science Centre at Health Data Research UK.
The study is the largest of its kind in this population, and is published in The Lancet Child and Adolescent Health. It was led by scientists at the Universities of Cambridge and Edinburgh, and University College London, with support from the BHF Data Science Centre at Health Data Research UK.
Principal author Dr Alexia Sampri, University of Cambridge, said:
“Our whole-population study during the pandemic showed that although these conditions were rare, children and young people were more likely to experience heart, vascular or inflammatory problems after a COVID-19 infection than after having the vaccine — and the risks after infection lasted much longer.”
The research team uncovered these findings by analysing linked electronic health records (EHRs) for nearly 14 million children in England under the age of 18 between 1 January 2020 and 31 December 2022, covering 98% of this population. During this period, 3.9 million children and young people had a first COVID-19 diagnosis. And 3.4 million had a first COVID-19 BNT162b2 (Pfizer–BioNTech) vaccine, the main vaccine used in 5-18-year-olds during the study period.
(Continue . . . )
While all of this should be highly reassuring to parents considering the COVID vaccine for their kids, the reality is, most people will probably never see it.
It isn't `click-baity' enough for social media, and frankly, it challenges our increasingly laissez-faire post-pandemic public health policies.
But at least its out there, for anyone who cares to read it.
https://afludiary.blogspot.com/2025/11/the-lancet-vascular-and-inflammatory.html