I’ve Read 3,000 Studies About COVID: Here’s What You’re Ignoring That Could (Still) Harm You or a Loved One
Six years ago today, on December 31, 2019, the World Health Organization (WHO) Country Office in China was informed of several cases of a pneumonia of unknown etiology that seemed connected to the Huanan Seafood Wholesale Market. We all know what happened next. What most do not seem to know is that research continues to accumulate as to the chronic and long-term risks of repeated COVID infections. I’ve read the findings, discussions, and conclusions of more than 3,000 studies, including over a hundred published just this month, and I wish more people appreciated the risks they’re taking.
People hearing what I’ve learned often jump to the false dichotomy of either doing nothing to protect yourself or returning to the dark days of being isolated at home with business and school closures. No one is suggesting you need to stay home. I don’t! But what I’ve taken from the medical research I’ve reviewed is that I need to be a little more aware of and careful about the risks I choose to take. Maybe, after reading what I have to share, you may decide the same.
Before continuing, I’ll also acknowledge that I am not a medical professional, but you don’t need to be one to understand much of the research. Even if you don’t know the difference between P53 (a tumor-suppressing protein that is downregulated by COVID), C-reactive protein (a protein that rises following COVID infections and signals inflammatory processes), or T cells (a type of white blood cell that protects you from disease and is reduced after COVID infections), you can still learn from the hard work of thousands of medical researchers studying COVID’s longer-term impact.
I will first share some plain-language conclusions, and then, for those with more curiosity, I’ll share links to hundreds of studies validating those conclusions.
What We Know About COVID Infections and Reinfections
Everyone already knows the good news: COVID no longer fills up hospitals. And, while it still caused around 20,000 U.S. deaths in the past twelve months (a number that is certainly undercounted), severe acute illness causes substantially fewer hospitalizations and deaths than in the early years of the pandemic. Thanks to some immunity created by a combination of prior infections and vaccinations, COVID is no longer a “novel” virus but one against which our body has some incomplete defenses. That does not mean it’s safe to be repeatedly reinfected with COVID, however.
Now, the bad news. Research and data tell us that:
- COVID isn’t “just the flu” — it surges twice as often, never goes away, and is associated with much greater health risks than influenza: COVID never became a seasonal virus; unlike influenza, which surges once a year each winter, COVID causes two significant waves of infections annually in the US. Moreover, while influenza infections virtually disappear much of the year, COVID is always circulating, per wastewater analysis, an effective measure of viral risks. We also can see this in hospitalization data — in the first week of September 2025, COVID hospitalized 2.6 of every 100,000 Americans, while, at the same time, influenza hospitalized 90% fewer people. Moreover, multiple studies that compare the risks of influenza (which most of us get every eight to ten years) and COVID (which many get every two or three years) find that COVID causes a much greater risk of chronic symptoms lasting three to six months or longer. For example, a study published two weeks ago found COVID was associated with significantly higher (76%) 30-day all-cause mortality compared with influenza. (You’ll find dozens of additional studies on COVID and the flu at the end of this article.)
- Each COVID reinfection increases the risk of Long COVID and chronic health problems: If COVID was just a minor acute viral illness, it might not be terribly concerning that it is always present and surges multiple times a year, but reinfections bring accumulating health risks. The fact COVID can cause longer-term health problems should come as no surprise, since we already knew that about other viruses. For example, Epstein-Barr is one of the most common human viruses in the world, and long after one recovers from acute mononucleosis, an EBV infection can raise the risk of cancer. We shouldn’t take any viral infection as lightly as we do, but with COVID, a virus that reinfects people quite commonly, the risks are greater. Dozens of studies find that the more you get COVID infections, the higher your risk of Long COVID. (You’ll find many links to these studies at the end of this post.)
- Long COVID is not a single condition but a blanket term for different types of dysfunctions: Many seem to think Long COVID is an imagined disease, but in fact, it’s a recognized condition by the CDC, WHO, and even the U.S. Department of Health and Human Services, which recognizes Long COVID as a condition under the Americans with Disabilities Act. However, there are reasons people may be confused by Long COVID. It’s a new condition, and research is still lacking. Medical definitions of Long COVID can vary, although most define it as symptoms persisting three or more months post-infection. There are no established diagnostic criteria nor a single biomarker to diagnose Long COVID. And it’s possible there never will be a single way to define and diagnose Long COVID, as recent studies find that the condition we call Long COVID isn’t a single disease but has different phenotypes. Various studies find that people with Long COVID have a wide variety of health issues that can be clustered by chronic respiratory, neurological, cardiovascular, fatigue, pain, or multi-system involvement.
- There is no known treatment for Long COVID, many people recover slowly, but some suffer for years: Researchers are feverishly trying to establish treatments for Long COVID, but there is no approved treatment. There is no way to prevent or combat Long COVID besides avoiding another COVID infection. Many with Long COVID find they recover from their lingering Long COVID symptoms over the course of months. Others are not so fortunate, suffering from serious, debilitating, and long-lasting conditions.
- Even if you feel recovered from an acute COVID illness or chronic Long COVID, the virus can leave your body with subclinical damage that can cause profound health concerns over time: The term “subclinical” refers to a disease that is not severe enough to present symptoms, but subclinical problems can still be very serious. Research tells us COVID can leave many with subclinical damage to immune, cardiovascular, neurological, or respiratory systems. COVID infections are associated with a higher risk of major cardiac events, impaired immune systems, brain damage, psychiatric issues, sleep disorders, and autoimmune diseases such as diabetes. Early research also suggests COVID may also be oncogenic (meaning it encourages the development of cancer), but it will take more years of research to conclusively establish a link. (Again, you’ll find some pertinent research links at the end of this article.) No one knows how four or five COVID infections may damage the body, harm well-being, or encourage chronic illness, but what we do know about COVID infections should urge us to more caution.
- Although the risk of a COVID infection has been declining in recent years, we could yet see significant waves of infections. Over the last two years, COVID surges in the U.S. have been on a steady decline, thanks to the immunity we’ve accumulated from prior infections and vaccinations, along with the lack of a major new COVID mutation. We cannot count on that continuing, however. A new and highly mutated COVID variant (BA.3.2, nicknamed “Cicada”) has begun to gain traction globally. While most COVID variants are caused by minor mutations as the virus spreads from one person to the next, BA.3.2 is very different, having developed over the course of years within the body of an immunocompromised person who was unable to defeat the virus. As this new variant spreads and mutates further, COVID vaccination rates are plunging, with just 16% of U.S. adults and around 7% of children receiving the 2025/26 COVID vaccine. The declining vaccination rate, in combination with the threat from a new, highly mutated variant, could bring greater surges, more infections, and more Long COVID suffering in 2026. (It’s happened before — the largest wave of COVID infections was not in 2020, the first year of the pandemic, but in winter 2021/22 when the first Omicron variant spread widely.) Adding to the risks are two enormous global (possibly “superspreading”) events in 2026 — the Winter Olympics in Milan in February and FIFA 2026 in North America this summer — which could spread COVID and accelerate its evolution.
- Vaccines are generally safe and effective: There is a lot of confusion and misinformation out there about COVID vaccines. On the one hand, the COVID vaccine is associated with some risks, and vaccine effectiveness against infection drops quite substantially within three to six months after a jab. Neither of those are reasons to avoid vaccination, however. COVID vaccines, as with all vaccines and medications, have some risks — I mean, have you tried to read the warnings that come with your OTC or prescription medication recently? — but studies have established the overall safety and effectiveness of the vaccine. Moreover, while it’s disappointing the vaccine effectiveness against infection declines so rapidly, the data is quite solid that COVID vaccines provide more lasting protection against serious illness and may decrease the risk of Long COVID. Below, I provide a list of studies about the impact of COVID vaccinations, but one recent study deserves special attention since it evaluated four-year mortality across an enormous population of 28 million people, and it found, “no increased risk of 4-year all-cause mortality in individuals aged 18 to 59 years vaccinated against COVID-19.”
When I share this sort of information, one common response I hear is that if people were really getting less healthy due to COVID reinfections, we’d surely see the signs. Like, for example, an abrupt change in disabilities that started growing in 2021 and continues to rise? Or, maybe we’d see an unusual rise in cancers since the start of the pandemic? Or, perhaps younger people would start dying of heart attacks at younger ages? And if our immune systems were being damaged, wouldn’t we see a rise in infections such as measles, pertussis, and influenza? Obviously, broad population-level changes in health are complex and are due to multiple causes, including declining vaccination rates, but evidence is all around us that the health of many is changing.
Small Precautions Can Go a Long Way to Prevent an Acute illness, Long COVID Symptoms, or Serious Chronic Health Problems
When we ended the global health emergency, leaders said we could do so because we were armed with the tools we needed to protect ourselves. Then, we promptly ignored or ended those tools. Genomic testing, which helps to inform us of significant new variants, has decreased to disappointingly miniscule levels. Vaccines, which diminish infections and protect against serious illness, are disregarded by most. Wastewater testing, an effective tool for monitoring risks, is ignored. And, when wastewater tells us risks are high and rising, few make any changes to their behaviors. But, as I noted earlier, the answer isn’t to lock yourself at home but to become aware of the risks and react sensibly.
There are a couple of simple things to do to decrease our risks all the time, without any significant adjustments to our behaviors:
- Get vaccinated, as recommended. The current U.S. administration may cast doubts on vaccines, but the CDC still recommends an annual COVID vaccination! At the current time, most Americans haven’t received a vaccination in two or three years, significantly raising their risks of infection. And, more infections encourage larger surges, more COVID mutations, and larger numbers of people dealing with Long COVID issues.
- Improve the air we breathe. At home, at work, and elsewhere, we can do more to improve the quality of the air we breathe. Personally, we can open windows and use air purifiers to reduce infection risks. Also, we can urge business leaders, school officials, and others to implement safe air practices in communal spaces. The more we improve the air we breathe, the more we reduce illnesses and protect ourselves and our families.
There are also small actions we can take to ensure we and our families stay healthy, particularly during surges. When wastewater testing alerts us to increased risks, we can:
- Socialize with friends at home versus meeting in crowded bars and restaurants.
- Dine and socialize outdoors rather than indoors with crowds.
- Stay home when you’re sick. Don’t make your illness someone else’s chronic health risk.
- Wear a mask when commuting, traveling, or attending events.
None of this suggests you lock yourself in isolation. Knowing the risks can lead us to commonsense decisions that minimize our risks while still allowing us to enjoy life. People have adopted an attitude that COVID infections are inevitable, so they should do nothing to prevent them. That makes as much sense as saying auto accidents are inevitable, so why wear seatbelts? And, if you can change your plans or put on boots due to threatening or inclement weather, then there is no reason you cannot learn to adjust plans or wear a mask when infection risks are high.
I believe we’re in the “smoking era” of COVID. For decades, we had a growing awareness of the risks of smoking, but that didn’t mean everyone acted on that knowledge. About 42% of adults smoked in 1965. By 1989, it fell to 30%. In 2013, it was 19%. Today, just 11% of Americans report they smoked in the past week. Even with the dangers of smoking well known, it took decades for people to act, and in those intervening decades, millions suffered and died unnecessarily due to their smoking habits. Now that COVID’s risks are becoming established, will it take decades for people to act, and must we wait until millions have chronic illness or disability before we do so?
I can’t answer that question, but here’s an even better one for you: What will you do with this knowledge? Were the smart ones the people who ignored the risks of smoking and increased their chances of cancer, COPD, and death? Or were the smart ones the people who acted before others, reducing their risks and doing what they could to lead a longer, healthier life.
Links to the Details on COVID’s Risks
Some of you may not believe the conclusions above. This lengthy section is full of links to data and research that validate the risks of COVID. If you haven’t yet been convinced, here you go:
COVID infections are riskier than influenza infections: People are infected much more often with COVID, and COVID is not “just the flu”:
- “The research found that over 1 in 3 patients had one or more features of long-COVID recorded between 3 and 6 months after a diagnosis of COVID-19. This was significantly higher than after influenza.” 2021
- “Compared with seasonal influenza, covid-19 was associated with increased risk of mental health outcomes in people who both were and were not admitted to hospital.” 2022
- “The death rate at 30 days was 5.97% for COVID-19 and 3.75% for influenza.” 2023
- “the COVID-19 group had a significantly higher risk of the composite outcomes during all-cause ED visits, hospitalizations, and deaths when compared with the influenza group (27.5% vs. 21.7).” 2023
- “Over 18 months of follow-up, compared to seasonal influenza, the COVID-19 group had an increased risk of death (hazard ratio [HR] 1·51 [95% CI 1·45–1·58]), corresponding to an excess death rate of 8·62 (95% CI 7·55–9·44) per 100 persons in the COVID-19 group versus the influenza group.” 2024
- “Beyond the first 30 days after infection, patients with COVID-19 were at increased risk for incident AIRD (autoimmune inflammatory rheumatic diseases) compared with… influenza-infected control patients (adjusted hazard ratio, 1.30).” 2024
- “In this large real-world study, COVID-19 infections were associated with a 2.3-fold risk of developing AKI (acute kidney injury), a 1.4-fold risk of CKD (chronic kidney disease), and a 4.7-fold risk of ESRD (end-stage renal disease) compared to influenza.” 2024
- “COVID-19 represented a greater disease burden than influenza, with more hospitalisations and deaths, and more severe disease primarily among non-vaccinated and comorbid patients.” 2024
- “PICU (Pediatric intensive care unit) admission rates and oxygen support needs were similar in both groups. When the virus was COVID-19, it had 7.8 times higher risk of mortality compared to influenza.” 2024
- “Influenza had lower odds for requiring ICU admission, mechanical ventilation and in-hospital mortality compared to COVID-19 only.” 2025
- “COVID-19 was associated with more severe disease outcomes, including long-term mortality, compared with influenza or RSV.” 2025
- “COVID-19 represented a greater disease burden than influenza, with more hospital admissions and deaths, and more severe disease (primarily among non-vaccinated people, those with comorbidities, and male patients).” 2025
- “Among study participants with a documented infection, SCV2-positive participants had nearly twice the odds of ongoing symptoms as influenza-positive participants.” 2025
- “COVID-19 is associated with an increased risk of long-term renal dysfunction compared with influenza.” 2025
- “Among hospitalized SARI (severe acute respiratory infection) patients, the odds of severe outcome were higher for SARS-CoV-2 patients compared to influenza-positive patients for all periods, while the odds of death were higher for two periods.” 2025
- “Risks of post-acute cognitive impairment and fatigue/malaise were significantly higher post-COVID-19 vs influenza (cognition: aHR = 1.34; fatigue/malaise: aHR = 1.75).” 2025
- “Compared to influenza, COVID-19 was associated with diplopia and CN (cranial nerve) VI palsy.” 2025
- “COVID-19 is associated with markedly higher short-term mortality than influenza across diverse clinical and demographic subgroups.” 2025
Each COVID reinfection accumulates risks:
- “Compared to no reinfection, reinfection contributed additional risks of death (hazard ratio (HR) = 2.17, 95% confidence intervals (CI) 1.93–2.45), hospitalization (HR = 3.32, 95% CI 3.13–3.51) and sequelae including pulmonary, cardiovascular, hematological, diabetes, gastrointestinal, kidney, mental health, musculoskeletal and neurological disorders.” 2022
- “Reinfection seems associated with more prevalent severe long-term symptoms compared to a first infection.” 2023
- “In the Omicron cohorts, the estimated proportion of PASC positivity was greater among reinfected participants compared with participants with 1 reported infection.” 2023
- “The cumulative risk of long COVID as well as of various cardiac, pulmonary, or neurological complications increases proportionally to the number of SARS-CoV-2 infections, primarily in the elderly.” 2023
- “We report a consistent increase in the risk of persistent symptoms after reinfection compared to first infection. All post-acute COVID19 symptoms mentioned in the WHO clinical case definition appeared more common after reinfection than after a first infection, after matching by age, sex and date of infection.” 2023
- “Canadians reporting two known or suspected COVID-19 infections (25.4%) were 1.7 times more likely to report prolonged symptoms than those reporting only one known or suspected infection (14.6%), and those with 3 or more infections (37.9%) 2.6 times more likely.” 2023
- “Overall, these results demonstrate significant worsening of depression, stress, and anxiety symptoms coupled with improvements in attentional control abilities over time for repeatedly COVID-19-diagnosed individuals.” 2024
- “Long COVID-19 was more prevalent when subjects had reinfections (p = 0.02) and less frequent when they had a complete vaccination scheme (p = 0.05).” 2024
- “Compared to those with one SARS-CoV-2 infection, reinfected patients were at a higher risk of asthma (3.0; 1.32–6.84), COPD (3.07; 1.42–6.65), ILD (3.61; 1.11–11.8), and lung cancer (3.20; 1.59–6.45).” 2024
- “Overall, by 12-months, 17.4% of first-positives and 21.9% of reinfected CYP (children and young people) fulfilled the research consensus Long Covid definition.” 2024
- “For individuals with infection counts of two or more times, there was a statistically significant increase in general symptoms, cardiovascular symptoms, and neuropsychological symptoms. Additionally, the total distress score was notably higher in this group.” 2024
- “The cumulative risk of APC (post-COVID-19 illness) increases with the number of infections from 13% with one infection, to 23% with two infections and reaching 37% for three infections.” 2024
- “Both having Long-COVID at the 1-year follow-up and contracting a second infection were significant risk factors for presenting with Long-COVID at the 2-year follow-up.” 2024
- “Re-infected patients exhibited lower levels of brain activation and excitability compared to single-infection patients.” 2024
- “Participants with reinfection were associated with a higher probability of reporting headaches (OR: 1.54, 95% CI: 1.06–2.25), loss of or change in smell and/or taste (OR: 1.90, 95% CI: 1.27–2.83), impaired sleep (OR: 1.55, 95% CI: 1.02–2.35), and brain fog (OR: 1.76, 95% CI: 1.12–2.76).” 2024
- “Participants reporting multiple COVID-19 infections have a significantly higher prevalence of long COVID with the highest prevalence of severe long COVID (PR: 1.84, 95 % CI: 1.21, 2.80) compared with people that reported only one COVID-19 infection.” 2024
- “Here we show that reinfections increase the likelihood of reporting Long COVID, which increased 2.1-fold from one to two infections.” 2024
- “The multivariate regression analysis indicated that having two infections posed a significant risk for many long COVID symptoms, and the risk ratio increased exponentially when the number of infections exceeds two.” 2024
- “Those infected with Covid-19 twice or more were more likely to have Long COVID than those infected once.” 2024
- “The risk of developing post-COVID-19 syndrome increased for those… experiencing reinfections (OR 2.405, p < 0.001), while SARS-CoV-2 vaccination halved the risk (OR = 0.489, p = 0.004).” 2024
- “The participants who had a history of COVID-19 re-infection were 3.94 and 2.81 times more inclined to an inferior psychological and social QoL score, respectively in comparison to individuals who had not.” 2024
- “Participants with multiple infections (1.41 [1.33–1.50]) had a higher risk of any PCC compared to those with a single infection (1.10 [1.09–1.12]).” 2024
- “We found a significant association between the risk of experiencing PASC and multiple SARS-COV-2 infections (RR = 1.41 [1.14–1.74]).” 2025
- “Among patients with COVID-19 infection requiring hospitalisation, COVID-19 re-infection was associated with increased post-acute mortality and morbidity compared with first-time infection.” 2025
- “Risk-benefit analysis showed that a higher number of pre-existing comorbidities and multiple SARS-CoV-2 infections were the factors most strongly associated with increased probability of long COVID at six months post-infection.” 2025
- “Objective memory scores decreased significantly with increasing number of COVID-19 infections for the diagnosed long COVID group.” 2025
- “The odds of long COVID increased with reinfections (odds ratios for one reinfection 2.592 [95% CI: 2.188 to 3.061]; two or more: 6.171 [3.227 to 11.557]; all p < 0.001).” 2025
- “Children and adolescents face significantly higher risk of various PASC outcomes after reinfection with SARS-CoV-2.” 2025
- “Our final model identified significant associations between long COVID and two or more COVID-19 infections (OR = 23.725, 95% CI: 5.098–110.398, p < 0.0001).” 2025
- “For long COVID, older age (OR: 1.63, 1.38–1.93), female (OR: 1.19, 1.03–1.38) and SARS-CoV-2 reinfection (OR: 3.56, 2.63–4.80) were risk factors; while number of COVID-19 vaccine doses (OR: 0.87, 0.81–0.94) was a protective factor.” 2025
- “In elite judo athletes, reinfection with SARS-CoV-2 cause more severe respiratory dysfunction compared to primary infection, with notable impairments in maximal inspiratory pressure (MIP) and MEP by −14% and −13%, respectively, at 3 months.” 2025
- “The cumulative risk of long COVID increased with the number of reported COVID-19 infections, rising from 13.7% (95% CI, 13.1%–14.4%) for a single infection to 37.0% (33.0%–40.9%) for 3 infections in the online survey, and from 11.8% (a single infection) to 29.5% (≥3 infections) in the telephone survey.” 2025
- “In individuals reporting their first infection during the Omicron wave, the odds of reporting ≥3 symptoms after the most recent infection was higher in those reinfected than in those with a single infection (weighted adjusted odds ratio, 1.54).” 2025
- “Among individuals with multiple infections, the frequency of SARS-CoV-2 infection was associated with increased depressive symptoms.” 2025
- “The risk of Long COVID doubled for every additional confirmed positive COVID-19 test.” 2025
- “Long COVID prevalence was 3–10 times higher in individuals with three or more infections than in those with only one recorded infection.” 2025
- “The rate of Long COVID diagnoses has been increasing with each successive Omicron variant, which is particularly notable as there has been less follow-up time for variants such as Omicron BQ.XBB.” 2025
- “A significantly higher number of symptoms (were) reported by LC patients with three reinfections (M = 8.39, SD = 2.63), compared to those who experienced only one (M = 6.14, SD = 2.76; p =.002), or two reinfections (M = 7.00, SD = 2.87; p =.015.” 2025
- “Participants who had experienced two or more episodes of COVID-19 were 1.42 (95 % CI 0.98–2.05 and 90 % CI 1.04–1.95) times more likely to report severe symptoms compared to those with only one episode.” 2025
- “Reinfection was associated with a significantly increased risk of an overall PASC diagnosis (U09.9) (RR 2·08 [1·68–2·59]) and a range of symptoms and conditions potentially related to PASC (RR range 1·15–3·60), including myocarditis, changes in taste and smell, thrombophlebitis and thromboembolism, heart disease, acute kidney injury, fluid and electrolyte disturbance, generalised pain, arrhythmias, abnormal liver enzymes, chest pain, fatigue and malaise, headache, musculoskeletal pain, abdominal pain, mental ill health, POTS or dysautonomia, cognitive impairment, skin conditions, fever and chills, respiratory signs and symptoms, and cardiovascular signs and symptoms.” 2025
- “Among 2054 workers (1308 women, 746 men) aged 40–69 years, 486 developed Long-COVID (23.7%). Individual risk factors were… previous symptomatic vs. asymptomatic SARS-CoV2 infection (3.32; 2.19–5.06 for mild/moderate, 9.60; 6.10–15.1 for severe/critical).” 2025
- “Reinfection increases long COVID risk; however, the absolute increase after reinfection is smaller than that observed after a primary infection.” 2025
- “REST-Q (Restorative Sleep Questionnaire) scores decreased with increasing number of infections.” 2025
- “Compared with the first SARS-CoV-2 infection episode (reference), patients who experienced a second episode had higher odds of dyspnea (adjusted odds ratio; OR = 7.61; 95% confidence interval CI = 1.54–37.66).” 2025
- “The increase in IFN-γ in patients who had multiple episodes of COVID-19 may indicate persistent and possibly exacerbated immune activation after reinfections.” 2025
- “Hospitalization and COVID-19 reinfection significantly increased the risk of PASC, with reinfection raising odds more than 11-fold.” 2025
COVID vaccines are safe and effective:
- “Data from 40 health care systems participating in a large network found that the risk for cardiac complications was significantly higher after SARS-CoV-2 infection than after mRNA COVID-19 vaccination for both males and females in all age groups. These findings support continued use of recommended mRNA COVID-19 vaccines among all eligible persons aged ≥5 years.” 2022
- “COVID-19 vaccination protects against adverse maternal–fetal outcomes, with booster doses conferring additional protection.” 2023
- “This study found a significantly lower rate of mortality among individuals with myocarditis after mRNA vaccination compared with those with viral infection–related myocarditis.” 2022
- “The risk of death decreased with the number of COVID-19 vaccinations.” 2023
- “The risk of developing post-COVID-19 syndrome increased for those with more symptoms in the acute phase (OR 4.24, p < 0.001) and those experiencing reinfections (OR 2.405, p < 0.001), while SARS-CoV-2 vaccination halved the risk (OR = 0.489, p = 0.004).” 2024
- “Full vaccination and booster were associated with significantly lower risk of PCC compared to no or partial vaccination.” 2024
- “COVID-19 vaccination reduced the risk of post-COVID-19 cardiac and thromboembolic outcomes.” 2024
- “The pooled analysis found no significant increase in the risk of myocarditis among vaccinated pilots compared to unvaccinated pilots.” 2024
- “No increased risk of all-cause mortality or cardiovascular events was observed up to 180 days after any mRNA vaccination dose in the Omicron era; vaccination attenuated post-acute cardiovascular risk in older adults. The risk-benefit ratio of vaccination remained positive during Omicron.” 2024
- “The incidence of neuro-ophthalmic consequences following infection with COVID-19 is hundred-folds higher and associated with more harrowing systemic effects than vaccination against the virus.” 2024
- “The odds of brain fog significantly decreased with increasing vaccination rates.” 2024
- “Our data suggest that the increased risk of non-inflammatory CNS disorders following COVID-19 vaccination is lower than the risk conferred by COVID-19 infection.” 2024
- “The pooled OR (odds ratio) for receiving a new antidepressant prescription was higher for unvaccinated individuals than for those vaccinated.” 2024
- “Vaccination protects against adverse maternal–fetal outcomes and is now the most effective intervention for improving neonatal morbidity due to SARS-CoV-2 and can be administered at any time during pregnancy, with booster doses conferring additional protection.” 2024
- “Vaccination during pregnancy correlated with reduced symptoms and no hospitalizations.” 2024
- “For long COVID, older age (OR: 1.63, 1.38–1.93), female (OR: 1.19, 1.03–1.38) and SARS-CoV-2 reinfection (OR: 3.56, 2.63–4.80) were risk factors; while number of COVID-19 vaccine doses (OR: 0.87, 0.81–0.94) was a protective factor.” 2025
- “Vaccination offers substantial protection against long COVID.” 2025
- “Receipt of at least one dose of COVID-19 vaccine lowered the odds [aOR (95% CI)] for unexplained sudden death.” 2025
- “Importantly, recent large-scale studies have found no link between COVID-19 vaccination and SCA in young adults. Instead, prior COVID-19 hospitalization and modifiable risk factors play a more significant role.” 2025
- “C19V (COVID-19 vaccination) was not associated with an increased RR of vascular access interventions at any post-vaccination time point. However, C19D (COVID-19 disease) was associated with an increased RR after the first month (RR: 1.5–1.8) with the risk persisting for at least 4 months post-infection.” 2025
- “Vaccination against SARS-Cov-2 appeared to imply a higher overall recovery rate for all neurological symptoms.” 2025
- “Full COVID-19 vaccination significantly reduced the risk of POD (postoperative delirium).” 2025
- “Full COVID-19 vaccination may be linked with improved long-term outcomes in glucose regulation and cardiovascular stability. Conversely, unvaccinated individuals experienced ongoing glycemic dysregulation and an increase in hypertension prevalence.” 2025
COVID increases cardiovascular, neurological, immune system, and other risks: Rather than continue to post a long list of studies and links, I invite you to visit my spreadsheet of 3,000 studies. You’ll find ample evidence that COVID damages hearts and blood vessels, raises risks of embolism, strokes, and heart attacks, impairs the immune system, damages brains, increases mental health disorders, creates risks in pregnancies, damages kidneys, impairs sleep, raises the risk of diabetes and other autoimmune diseases, and is associated with changes that may encourage cancer:
I hope this information might help you to better understand the continuing risk of COVID and, perhaps, bring a little more safety into your life. Stay safe, friends.

