inflammation

New Data On COVID Vaccine Deaths

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There are two ways to be fooled. One is to believe what isn’t true; the other is to refuse to believe what is true.”  - Soren Kierkegaard

Two years ago, a Kaiser Family Foundation poll showed that 34% of Americans believe that the COVID vaccines have caused thousands of sudden deaths. As a result, some health departments have been forbidden from promoting the shots or have had to even ban them. Furthermore, despite clinical evidence to the contrary, 27% of people believe that the vax itself causes infertility-it does not, and 31% still believe that the anti-parasite drug, ivermectin, effectively treats COVID-it has been proven not to.

The rumor of “thousands of deaths” was partly driven by viral videos of young, healthy athletes collapsing on the field, alleging COVID vaccines were to blame. One of the most promoted of the videos, Sudden Death, has been exposed in these pages and by others as fabricated and blatantly dishonest. In many of the examples shown in the video, it has been proven that the collapsing athletes hadn't received a COVID shot, and deaths that did occur happened well before COVID vaccines were even available! Absolutely no evidence for a vaccine-related death can be found in that video.

After the real on-field cardiac arrest of the Buffalo Bill's Damar Hamlin in 2023, another unsubstantiated rumor by Peter McCullough, an MD darling of the anti-vax crowd, reported that sudden deaths in athletes had increased dramatically after the vax rollout. But, an epidemiologist who dug into McCullough’s data, found that his numbers were inaccurate and inflated–for example, some of the "young athlete deaths" were not actually healthy athletes who died suddenly on the field, but instead were random news reports of people of all ages dying from many different causes, including an elderly woman who died at home! McCullough is now hyping a non-existing health problem in the US so he can sell people his nostrum he claims mitigates the problem. Go figure.

Cardiac arrest. In contrast to all this disinformation, a new study published in the Journal of the American Medical Association last February specifically looked into vaccine-associated deaths. It examined whether there was any increase in sudden cardiac arrest (SCA) (where the heart suddenly stops, but the person survives), or in sudden cardiac death (SCD) in young US athletes after either the appearance of COVID (2020) or the introduction of COVID vaccines in 2021.

The study found no association between the vaccine and cardiac problems. The highest year for both sudden cardiac arrest and death in the study was 2017, well before both the virus and vaccines were on the scene. Furthermore, the incidence of cardiac-related deaths did not change much from year to year, even AFTER the appearance of the virus or the vaccine! This is shown by the figure below (also notice how small the actual numbers are).

FigureAstley et al, JAMA, 2025

This finding is further supported by other studies that also have shown no increase in cardiac arrest in young people in general (ages 5-50) during the COVID vaccine rollout in Australia, and an overall decreasing rate of rare sudden cardiac deaths in NCAA athletes during the COVID vaccine roll out in the US.

Myocarditis. Many conspiracy theories are rooted in partial truths that are overinflated and vaccine-induced myocarditis is no exception. There are real, but very rare, documented incidences of myocarditis (inflammation of the heart) after getting a COVID vaccine. Research from the Yale School of Medicine indicates that myocarditis happens in 0.036% of males age 12-17 after an mRNA vaccine. In contrast, this same age unvaccinated group experiences myocarditis twice that rate after COVID infection; thus the vaccine actually protects against the inflammation. Furthermore, vaccine-associated myocarditis is milder than other forms of myocarditis and patients quickly recover.

Bottom line. In reality, serious adverse events were very rare in large, randomized mRNA vaccine trials and occurred at a similar rate among people who got the vaccines and those who got the placebos. Finally, if the vaccines are so dangerous, why does the evidence proving that need to be fabricated?


SARS-CoV-2, A Respiratory Virus That Messes With Your Gut

The CoV-2 virus that causes COVID is a respiratory bug, right? They say we catch it, not from surfaces or food, like we do norovirus, but from airborne exposure—we breathe it in. That of course, means that it causes respiratory problems. Makes sense, right? Well, Sarah Carter, 36, from San Mateo, CA, caught the virus in late 2023. Her main symptom was not respiratory but relentless diarrhea that became so sever she had to take an ambulance to the ER. The runs caused her to become dehydrated, which in turn caused a spike in her blood pressure and heart rate. She urgently needed IV fluids to treat it all. After three more days of diarrhea she finally felt better. But, six months later the GI symptoms reappeared overnight without her being infected again. Nearly everything she ate set off diarrhea. She also had bloating and pain so severe that she said it felt like acid was running through her intestines. A gastroenterologist eventually diagnosed her with post-infectious irritable bowel syndrome (IBS).

What in the world is a respiratory virus doing messing with her entrails, especially months after being infected? Did it make a wrong turn somewhere?

We have gotten accustomed to testing for COVID when we feel crummy and run a temperature, have a sore throat, runny nose, loss of smell, cough, etc.—all symptoms of respiratory infection. But Dr Rohit Jain, an internal medicine doc at PennState Health told Time that when someone complains of problems affecting the exit at the other exit of the body: i.e., nausea, diarrhea, vomiting, etc., he always tests for COVID. Another doctor, Mark Rudd, chief of infectious diseases at the U of Nebraska Medical Center also weighed in saying that, “COVID-19 is really a GI-tract disease.”

What??

If it “really is a GI disease” why are we wearing masks, distancing, and worried about respiratory infection rather than hand washing and sanitizers??

The SARS-CoV-2 virus and its disease, COVID, are very strange and threw the medical establishment for a loop after they first appeared on the scene at the end of 2019, and after COVID became a world-wide pandemic in early 2020. Docs dealt with myriad, seemingly unrelated symptoms in different patients; symptoms such as brain fog, loss of smell, severe pneumonia, hemorrhage issues that led to black toes and lungs that looked like they had filled with chocolate pudding, among many others; all from the same virus. Now add to that befuddling mix, GI problems to what was believed a respiratory virus,and COVID presents a conundrum. Docs have to now factor in the fact that many people experience no, or only mild gastrointestinal symptoms, while other patients experience significant digestive problems that can distract from the pulmonary problems which complicate diagnoses.

As we have learned more about COVID over the last few years, it has become clear that infection symptoms can also include loss of appetite, nausea, vomiting, diarrhea, and stomach pain, according to Jain’s research. A 2023 study published in Nature Communications reported that 36% of COVID patients are likely to develop GI disorders such as ulcers, pancreatitis, IBS, and acid reflux. Another recent study in Clinical Gastroenterology and Hepatology found that 40% of adults hospitalized with COVID, had at least one GI relapse a year or more later. While both of these were small studies, they are in close agreement regarding the incidence of COVID GI problems. And like other symptoms of long COVID, the GI problems can last many weeks. That is quite concerning. Weeks of diarrhea, for example, is much more than an immense inconvenience and major mess, it is a serious medical issue. But not all patients experience these symptoms, just like not all patients lose their sense of smell, had black toes, or developed long COVID. Try to diagnose and understand COVID with this range of variable symptoms! How confusing.

How can the same virus cause runs from both ends of the body; the nose and the other end?  Among the things we have learned over the last few years is that the CoV-2 virus infects cells that express the ACE-2 protein. While ACE-2 normally is important for certain cell functions, the virus decided to use it as a receptor on which to grab onto and then enter cells. The protein is found on many different types of cells throughout the body, but it is expressed in especially high levels in the lungs, which helps explain COVID’s respiratory symptoms. It turns out that ACE-2 is also highly expressed in cells of the GI tract. That explains the intestinal complications. Also, because it is found in the GI tract that could possibly make feces from infected animals, like bats, a great way to widely spread the virus to other animals, just like migrating birds spread the avian flu virus to poultry flocks and dairy herds. In fact, in 2012, six Chinese mine workers removing guano in a bat-filled cave where flying flittermice were found with COVID, developed severe respiratory symptoms. Three of them died. COVID infection from contaminated bat guano is suspected because the Wuhan lab eventually found evidence of an unknown coronavirus in the patient samples. But, this was years before the CoV-2 virus had been discovered, so the CoV-2 link to their disease comes with some uncertainty. Maybe the virus in ca-ca could be a way to spread it between people too, like norovirus is spread. To my knowledge, human-to-human spread this way has not been shown, but it makes sense to this scientist that it could. After all, since the virus is found in feces, wastewater surveillance has proven to a useful tool for tracking CoV-2 spread among human populations. It is routinely found in poop, and there is a good possibility that the Chinese workers caught it from the bat scat they were shoveling. Together, that makes it very likely that humans can spread it to other people via unsanitary practices. But, at this time, that is just the opinion of your sometimes humble correspondent. We will see.

We also now know that the virus can hide in the nooks and crannies of the  bowel for months, or even years, according to Ziyad Al-Aly, MD, an epidemiologist at the Washington University School of Medicine in St. Louis, who co-authored the Nature Communications study on chronic post-COVID GI symptoms that was cited above. This might explain why gut-related symptoms can long outlast the initial acute infection. But other possibilities to explain long-COVID GI problems continue to be investigated. This is another “we shall see” issue.

We also know that the virus can cause widespread and sometimes long-lasting inflammation, potentially affecting various organs throughout the body including the gut. GI inflammation can affect the gut microbiome, which is the collection of microbes that normally live in the GI tract and that are good for us. We have long known that changes in the gut microbiome can have manifold health effects affecting GI health, and even the well-being of the heart, kidneys and brain, including Alzheimer’s disease, which is a possible complication of COVID. Disruption of the GI microbiome also is related to obesity and diabetes and it is notable that COVID disease also is associated with new-onset diabetes. Inflammation in the gut can also damage the lining of the intestines, making them “leaky” so that nutritional goodies from foods you normally would absorb across your gut into the blood stream, instead escape into the abdomen, causing immune cells to mount an allergy-like response to foods. COVID-induced inflammation can also chew away at the nerves that control normal gut contractions (peristalsis) that move food along, and interfere with neurological signals in the gut causing pain. Not fun, ask Sarah Carter!

Since the start of the pandemic in early 2020, GI docs have noticed an uptick in IBS in COVID patients. Medical scientists have long known that other gastrointestinal infections, like those from norovirus, giardia (a parasite), or salmonella (bacteria), can lead to IBS as well as functional dyspepsia, a type of chronic indigestion that causes frequent feelings of fullness and stomach pain or burning, like acid running through your innards. Does that sound familiar? Now we can add the respiratory virus, CoV-2, to the list of infectious agents that can cause IBS and other digestive problems.

Bottom line: So, gut problems are added to the manifold issues associated with COVID disease. CoV-2 is a nasty bug that you don’t want to catch. Get vaccinated and spare yourself all these problems!


Infections Can Cause Brain Atrophy And Dementia

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“We could certainly slow the aging process down if it had to work its way through Congress.”
 -Will Rogers

Two provocative areas of research have led to the notion that infection could be a risk factor for dementia. On one hand, some studies have directly suggested that there is a possible link between some infections and an increased risk for Alzheimer’s disease (AD). Then, other studies found that two vaccines, the flu shot and the shingles vaccine, reduced the risk of dementia. Together, all this led to the hypothesis that infection might play a role in neurodegenerative diseases. This is now bolstered by a new study published last August in Nature Aging that identifies possible post-infection immunological/inflammation drivers that lead to brain atrophy and subsequent cognitive decline.

Brain atrophy! It can easily be detected via modern imaging technology, and it is not good.

We have abundant evidence that even minor infections can change the way we think and behave. More-severe infections that result in delirium have long been associated with long-term cognitive problems. Even shingles, which is a very painful relapse of chicken pox (you never clear the virus, which resides in your nerves) also is associated with dementia. There is a very effective vaccine that stops shingles in its tracks and it has been shown to reduce the risk for dementia later in life by up to 50%. The more severe an acute infection or its relapse, the greater the inflammation caused by the immune response, and the greater the risk of Alzheimer’s and other types of dementia. Therefore, it makes abundant sense that vaccines, which greatly reduce the severity of infectious disease, would also lessen the risk for dementia as well as for other long term post-infection health problems such as diabetes, Parkinson’s diesease, and maybe cancer that I have mentioned in these pages.

The link between infection and cognitive problems seems to hold with different types of infections, whether they are bacterial or viral. Of the 15 types of infections studied, six—flu, herpes (which includes small pox, chicken pox, shingles, etc.), respiratory tract infections, and skin infections—were associated with increased risk of atrophy in the brain’s temporal lobe. This region includes the inner folds of the temporal lobe where a rather small organ called the hippocampus sits on each side of the brain. This is part of what is called the limbic system, which manages the functions of feeling and reacting, and helps us process and retrieve two types of memory, declarative memories and spatial relationships.

Declarative memories are those related to facts and events such as learning how to memorize speeches or lines in a play. Spatial relationship memories involve pathways or routes. For example, when a cab driver learns a route through a city, they use spatial memory and that learning can actually increase the size of the hippocampus. Spatial relationship memories appear to be stored in the right hippocampus. In addition, short-term memories are converted into long-term memories in the hippocampus, but are then filed away long-term elsewhere in the brain. So, with a malfunctioning hippocampus, these short term memories do not get stored. And we forget things.

We have known about the hippocampus (or hippocampi, since we have two of them) for more than four centuries. The surgeon, Julius Caesar Arantius, first discovered the hippocampus in 1587, coining the term from the Greek word for seahorse (hippokampos) based on its shape. It does resemble a seahorse. This region, critical for memory and learning, is strongly affected in AD where the shrinking size of the hippocampus can be used to monitor the progress of the disease.

The latest study relating infection to dementia was based on data from the Baltimore Longitudinal Study of Aging, one of the longest-running studies of human aging in the United States. They also used neuroimaging to track how brain volume changed in 982 adults, with or without a history of infection. This began in 2009 and its data confirmed findings from analyses of UK Biobank data of almost 500,000 people, and a Finnish dataset of almost 300,000 subjects, both of which identified these infections as risk factors for dementia.

Of course, most of these studies were done before COVID. COVID has not been around long enough to definitely tell us whether the disease is also linked with increased risk of dementia, but as a respiratory infection accompanied by severe systemic inflammation, we can expect it to be.

Bottom line: Vaccines not only protect against the acute infection they were made for, but they also protect against serious post-infection complications such as new onset diabetes, Parkinson’s disease, perhaps cancer, and other long term complications of infectious disease, which now also includes dementia.

Get vaccinated!


COVID On The Heart

“We will see….”

I often end these blog posts that describe the confounding nature of this brand new SARS-CoV-2 virus and its novel disease, COVID, saying, “We will see.” The virus and its disease, both, have been very unusual and medical science has been continually trying to catch up with it and understand new issues they present. Hence, novel information we have been gathering takes a while to understand, so "We will see" is an appropriated disclaimer.

After four years dealing with all this, our vision is gradually improving. For instance, we are getting a better handle on how infection with the virus affects the heart.

Sadly, too many armchair medical conspiracists still frequently sound off that mRNA vaccines are causing thousands of deaths due to cardiovascular problems they cause. They do so without ever proffering credible evidence to support their notion--they simply claim that it is self evident. The truth is that the vaccines are not doing that in any significant number as I previously debunked here, here, here and especially here. Several clinical trials done before the vaccines were released demonstrated that cardio risk from the shot is negligible, and when it occurs it is inconsequential and usually accompanied by no symptoms. It is just detected via blood test. This has since been confirmed in a billion people around the world who have gotten several billion shots as investigators continue to follow the outcomes of vaccinated people in what are called, “post-market studies” or "phase 4 trials." Rather, it is the virus that is causing almost all the cardiovascular problems and this is well established by the research.

We do know that between March 2020 and March 2022, there were ~90,000 more cardio deaths in the US than expected. Most of these were in people 65 and older who have the highest risk for such problems, but heart-related deaths also jumped dramatically for healthy 25-44 year old COVID patients. How does the virus do this?

It is understood that CoV-2 infection and COVID disease cause widespread inflammation in the body, the vaccines, not so much in most recipients. General inflammation caused by viral infection is what increases cardio risk. The virus and disease stick around a while and so does the inflammation; the vaccine and its side effects do not. The immune system responds to this lasting infection, in part, by releasing hormone-like proteins that cause inflammation and blood clotting. Clotting and plaque accumulation in arteries lead to heart attacks or strokes. Smokers and those with high blood pressure often already have plaque in their arteries, so it is no surprise that these folks are at the highest risk for COVID-caused cardiovascular problems.

Even without pre-existing plaque, virus-induced inflammation in blood vessels alone can lead to clot formation, even in the absence of other high risk factors. That helps explain how younger, healthier people also show increased risk for cardio problems after infection with the virus.

We have also learned that even if you had COVID a year ago and cleared it, you remain at long-term risk for all cardiovascular problems according to a large study that analyzed medical records of almost 700,000 patients. The stroke risk is 1.5 times elevated; risk of heart attack is doubled; and the risk for different types of arrhythmias increases 1.6-2.4 times. Some of this elevated risk comes from the ability of COVID disease to induce new-onset high blood pressure in some people. Why this particular consequence to infection happens is another “we will see” question.

The good news is that vaccines reduce all this risk. Other studies showed that people who are vaccinated are roughly 40 to 60 percent less likely to have a heart attack or stroke following a COVID infection than those who are unvaccinated. This may be because vaccinated people are less likely to develop severe COVID. The greater the severity of disease means that the patient experiences much more inflammation which in turn leads to greater risk of cardio problems.

Again, the risk of the vaccine causing myocarditis is way overblown and those who continue to harp on this are spreading disinformation. The risk of myocarditis following infection is 4-8 times greater than following the vax, not the other way around. Don’t believe these lies, which cannot be supported by medical science, only by salacious rumor.

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The Long Haul, Part 4: The Cost of Long COVID In Terms Of Individual Health And Quality Of Life

Surviving COVID-19 is one thing, recovering is another.

My frustration with those who would minimize the impact of COVID-19 is reaching an apex. I constantly have to deal with their baseless rationalizations that “it is just a cold,” or “it only kills 0.01% of people” (actually the number is 2% around the world), etc. And I constantly reply to these iconoclasts that COVID has become, by far, the leading killer in the US. I also explain over and over that treating simple mortality percentage as the only relevant statistic to consider is falderal. For example, the Spanish flu also killed “only” 2% of those infected, but in just 24 weeks, that virus killed more people around the world than were killed in WWI AND WWII together! The percent figure is meaningless without considering the percent of what. Why do they continue to ignore the devisor and, hence, the total number of deaths?

A small percentage of a very large number is, in fact, another large number.

Those who wish to downplay the significance of the pandemic only focus on this mortality percent, but mortality is NEVER the whole story for any pandemic. A serious person will also consider the morbidity caused by the disease. In fact, the major CDC publication on health in the US is called the Morbidity and Mortality Weekly Report. Notice that it considers both morbidity and mortality, and further notice that morbidity is listed first in the title. I have made three prior posts in this series on Long COVID, about the significant lasting morbidity of COVID-19. You can see these posts here, here, and here. In those posts, I shared data showing that some ~10-30% of COVID survivors suffer serious health problems that last months.

In those posts, I mentioned the cases of a young, healthy MD, and of a young, healthy journalist, both of whom struggled with long COVID, and how it affected their careers and cost them thousands of dollars in out-of-pocket expenses for the dozens of tests and doctors they needed. In an article in Maclean’s magazine, a reporter interviewed many Canadian long COVID patients and heard how their lives have been turned upside down. They reported that they are unable to live like they used to and care for their families, do anything mildly strenuous, or even cook their meals. They spend long stretches of time in bed. Many of those interviewed had not returned to work several weeks after recovering from the acute disease.

Anecdotes like these have been repeated millions of times around a world that, according to the Johns Hopkins University COVID tracker, has seen more than 330 million cases of COVID (and this is a significant undercount since many countries do not record these data well). Research has corroborated these anecdotes.

+++

Common long-term symptoms include debilitating fatigue; respiratory problems; and “brain fog.”  Other common symptoms include compromised function of the heart, and kidneys, which sometimes require transplantation. Wide-spread clotting problems can cause significant illness and even limb amputation. There also are frequent neurological and neuropsychiatric symptoms as highlighted in Part 3 of this series. Surprising manifestations continue to emerge, such as new-onset diabetes.

Lung scarring often occurs in patients who experienced COVID-caused acute respiratory distress syndrome (ARDS), a common problem seen in acute COVID patients who required ICU care. ARDS is a serious respiratory problem that can be caused by different respiratory viruses and other things. About a third of patients with ARDS arising from any cause were unemployed 5-years later because of their lung damage. It is fully expected that patients with COVID-related ARDS will be found to fare similarly.

There also is the dysfunctional immune response common in many moderate to severe COVID cases that can cause long-term multi-organ damage, particularly in the liver and kidneys. It can also disrupt coagulation control of the blood, sometimes leading to amputations, mostly in patients in their 30s and 40s. It was reported that amputations due to vascular problems have doubled since the CoV-2 virus arrived. Compromised coagulation control in COVID patients can also precipitate adverse cardiovascular events such as heart failure, or hemiplegia due to strokes. Data from the COVID Infection Survey on long-COVID suggest that the risk of major adverse cardiovascular events and long-term illness is about ten times higher in COVID patients (even after mild COVID) compared to non-COVID matched controls. A Dutch study found that 31% of COVID ICU patients suffered thrombotic complications. These problems can unexpectedly pop up in people who had completely recovered from COVID.

A global survey tallied 205 different symptoms across 10 different organ systems that can persist after COVID infection has cleared. Typically, these manifold long COVID symptoms do not appear in isolation, but in multi-symptom clusters. A long hauler typically has several of these problems at a time.

While it is estimated that overall, 10-30% of COVID patients become long haulers, reports on the number of people suffering long COVID vary widely. Depending on the report, anywhere from 30-90% of COVID survivors suffer long term health problems. And even at the lower end of that range, 30% of over 330 million people world-wide who have been infected is a very large number. It represents an enormous personal toll in terms of lost health and diminished quality of life. Some of these reports are summarized below.

  • Half of 70,000 hospitalized UK COVID-19 patients experienced long-term complications, according to a study published in July. Complications occurred regardless of age group: For instance, 25% of adults aged 19-29 developed complications, as did 33% of those aged 30-39. Complications affecting the kidneys and respiratory system, liver injury, anemia, and arrhythmia were the most common.
  • Many COVID-19 survivors require extensive and prolonged rehabilitation. An European study found about one-third of 1,837 non-hospitalized COVID patients (i.e., those with mild disease) needed a caregiver three months after their symptoms started.
  • In April the CDC reported in its Morbidity and Mortality Weekly Report that 69 percent of nonhospitalized adult COVID patients in Georgia required
  • one or more outpatient visits 28 to 180 days after their diagnosis.
  • A study published last February in the Journal of the American Medical Association found that roughly one-third of 177 people who had mild COVID disease not requiring hospitalization reported persistent symptoms and a decline in quality of life up to nine months after illness.
  • 70% of people hospitalized for COVID-19 in the UK had not fully recovered five months after hospital discharge. They averaged nine long COVID symptoms requiring continued medical care.
  • A study in South Korea found that 90% of patients who recovered from acute COVID experienced long-term side effects.
  • According to a report in the journal, Lancet, 75% of people hospitalized with COVID-19 in Wuhan early in the pandemic, reported continued problems with fatigue, weakness, sleep problems, anxiety and depression six months after being diagnosed with the disease. More than half also had persistent lung abnormalities.

Data like these have been commonly reported around the world, pointing to a more chronic and expensive health problem than seen with the flu or common cold, which often is caused by different coronaviruses. A July 2021 article in Scientific American talked about how all of this indicates that long COVID will cause a “tsunami of disability” that will affect individual lives as well as create enormous strain on the health system. Consider the numbers: More than 60 million Americans (this is an underestimate since many COVID cases are not reported) have been infected with the CoV-2 virus. Therefore, if only 30% of these suffer long COVID, we are talking about 20 million long haulers and counting.

The related health care and disability costs of all of this are also still being calculated. How many “long haulers” will not be able to return to work for months, or at all? How many will need short-term disability payments, and how many will become permanently dependent on disability programs? As increasing numbers of younger people become infected, will we see a generation of chronically ill? This then moves us to consider the economic and financial cost of long COVID, which will be the topic of the next installation in this series.

Stay tuned.

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The Long Haul, Part 2: What Is Long COVID?

In the 1890s one of the biggest pandemics in recorded history, known then as the “Russian flu”, swept the world and killed one million people (for perspective, that is out of a world population about ¼ of today’s population). That “flu” is now thought to have been a novel coronavirus. Like the current coronavirus, SARS-CoV-2, the Russian “flu” was a new human pathogen so few people had any natural immunity to it and it was quite lethal. Not only that, but as the pandemic waned, it left in its wake a global wave of long-lasting neurological problems in the survivors. A similar long-lasting post-acute disease wave followed the next big pandemic, the “Spanish” flu of 1918 (which really was due to the influenza virus). The common symptom following the Spanish flu was lethargy so bad that in Tanganyika (modern-day Tanzania), for example, it caused a famine because people were too debilitated to pick the harvest. Other viral outbreaks, including SARS, MERS, and Ebola, also have been associated with long-term sequelae in survivors. However, today’s long COVID complications are far more common and far more variable than the persistent symptoms following these other viral pandemics. The variety of unrelated long COVID symptoms has flummoxed doctors hard pressed to diagnose and, hence, treat the constellation of chronic problems that appear in each patient.

As I wrote in Part 1 of this series, a wave of what has become known as “long COVID” is emerging in many people who have recovered from the acute disease. A recent review chronicling the effects of long COVID reported that “long haulers” commonly experience fatigue, sleep problems, and joint and muscle pain long after their bodies cleared the virus. Other symptoms range from the mundane to the bizarre: brain fog, shortness of breath, fatigue, tremors, tooth loss, racing heart, glaucoma, and diabetes among others. Long haulers are also at a significantly increased risk of dying months after infection. A large study found that after surviving acute COVID-19, patients had a 59% increased risk of dying within six months after their initial diagnosis. This translates into an extra eight deaths per 1000 patients. Thus, the consequences of the acute disease itself are just the tip of the iceberg.

Because the official definition of the chronic problem is fluid, we are still learning what this new malady is. A UK study published last December simply defined the syndrome as a collection of symptoms lasting for more than 28 days after initial diagnosis. However, another British study as well as Britain’s National Institute for Health and Care Excellence vaguely and broadly define long COVID as “signs and symptoms that develop during or after an infection consistent with COVID-19, and that continue for more than 12 weeks and are not explained by an alternative diagnosis”. It does not specify a list of what the symptoms are.

But, there are many. A global survey tallied 205 different symptoms across 10 different organ systems that can persist after COVID infection has cleared, including those affecting the heart, lungs, gastrointestinal system, muscles, and joints. There also are frequent neurological and neuropsychiatric symptoms as highlighted in Part 1 of this series. A sufferer typically has several of these problems at a time (14 different symptoms on average), with the most debilitating usually being one of three: severe breathlessness, fatigue, or “brain fog”. Other common symptoms included compromised function of the lungs, heart, and kidneys sometimes requiring transplantation. There also have been skin rashes, and newly diagnosed diabetes.

What exactly is long COVID? About the only thing we can say with any certitude at this time is that long COVID exists but is not easy to describe, possibly because it really is more than one malady. The only constant between different long COVID patients with different symptoms is that the conditions are a collection of varied symptoms that persist long after the acute disease subsides, which sounds as vague as the British definitions described above. Long COVID clearly represents a new health malady or maladies since it is not generally found in uninfected people, but is common in COVID survivors; yet not all COVID patients experience it. Long COVID can affect any post-COVID patient at any age, but it mostly presents in middle-aged people and seems to slightly prefer women. Even people with asymptomatic CoV-2 infection can have late arising effects that fit the profile of long COVID.  Multiple studies have shown that infected people who do not get acutely ill can still show irregular lung scans, for example. One such study found that nearly 60% of people with asymptomatic infection showed some lung inflammation in CT scans. Other studies have shown that young people with asymptomatic or mild infections can have long lasting cardiac issues, while others show signs of small blood vessel damage.

Some of these symptoms can be similar to other recognized, if not fully understood chronic problems, such as chronic fatigue syndrome (CFS), which is one of the most common complaints that long haulers have. CFS remains a mystery malady with an unknown cause, but it often follows a viral or bacterial infection. It is, therefore, possible that long-COVID CFS-like problems might be no different from classic CFS. It also is possible that CFS-like long COVID symptoms are not at all related to what is recognized as classic CFS, and they are simply different illnesses with similar symptoms. Time and research will tell.

Broadly speaking, there are three types of long COVID patients, according to one NIH scientist. The first are generally characterized by “exercise intolerance”, meaning they feel out of breath and exhausted from even mild physical activity. The second are characterized by cognitive complaints like brain fog and/or memory problems. The third type experiences problems with the autonomic nervous system, which controls things like heartbeat, breathing and digestion. Patients in this group suffer from symptoms such as heart palpitations and dizziness. Impairments of the autonomic nervous system are known as dysautonomia, which is an umbrella term for a variety of syndromes. Physicians treating long-COVID patients say there has been a marked increase in dysautonomia since the pandemic began. A rehabilitation doctor at Mount Sinai Hospital, in New York, says that roughly 80% of people who show up at his long COVID clinic have dysautonomia of one type or another.

Not only do long COVID patients suffer chronic debilitation, they also are at increased risk of dying. One of the largest studies of Covid-19 “long haulers” found that COVID survivors had a 59% increased risk of dying within six months after contracting the SARS-CoV-2 virus. The excess mortality translates into about 8 extra deaths per 1,000 patients. Thus, the pandemic’s hidden toll is that many patients require readmission, and some die, weeks after the viral infection abates.

What causes long COVID? What causes the myriad of symptoms lumped under the long COVID umbrella are being studied, but it seems that not all are actually caused by the CoV-2 virus. Based on what we have gleaned from observations of a few million long COVID patients around the world, the focus is on three possible biological explanations. One is that long COVID is due to a persistent viral infection. A second possible cause could be an autoimmune disorder. The third possibility is that it is a lingering consequence of tissue damage caused by inflammation during the initial, acute infection.

Supporting the first hypothesis that the infection persists even after COVID disease has passed is that some patients very slowly clear the virus completely. The virus or its remnants persist along with the long lasting symptoms. These patients are not infectious so it could be that they harbor some altered form or fragment of the bug which does not replicate, but is nevertheless making some viral product that their bodies are responding to. This is known to occur with other viruses, including measles, dengue and Ebola. RNA viruses are particularly prone to this phenomenon, and CoV-2 is an RNA virus. Direct proof of this hypothesis is lacking, but pertinent clues abound. A study published recently in Nature showed that some people had traces of CoV-2 proteins in their intestines four months after they had recovered from acute COVID-19. Viral products from CoV-2 have also been found in people’s urine several months after their recovery. All this is circumstantial evidence, to be sure, but viral persistence is consistent with long COVID in certain patients.

The second hypothesis, that long COVID is an autoimmune disease, holds that the virus causes something to go awry with the immune system inciting it to attack some of the body’s own tissues. Some evidence backs this idea, too. The immune system is a complex, tightly regulated machine designed to discriminate between your own cells and foreign entities such as viruses. Sometimes this ability to distinguish self from non-self fails and an immune response is generated to one’s own tissues. Some patients suffering from long COVID have badly behaving macrophages, which are immune cells responsible for gobbling up foreign invaders and displaying them to immune cells inciting them to make antibodies or to kill infected cells. Other long COVID patients exhibit abnormal activation of their B-cells, which churn out antibodies against the pathogen that can sometimes cross-react with the body’s own cells causing complications. Since antibodies circulate for several months after an infection, it makes sense that this could cause problems months after recovery from the disease. Again, this evidence is circumstantial, but consistent with the observations in some long haulers.

The third hypothesis about the cause of long COVID holds that the body’s inflammatory response during the acute illness causes long-term damage to cells and tissues leading to chronic inflammation. This sometimes happens with other viral diseases, but it could be particularly likely with COVID-19 since out-of-control inflammation, caused by a cytokine “storm” is a common hallmark of severe cases of acute illness. One guess is that the inflammation damages parts of the autonomic nervous system, or that the virus might damage the cells that line blood vessels, either by infecting them directly and/or via inflammation from the immune response. This could change the way blood flows to the brain and other organs, and may thus explain the brain fog and other organ failure that is sometimes seen. This too remains circumstantial, but consistent with current observations in certain patients.

Bottom line: Long COVID probably embraces several different chronic conditions with different causes. Studies to investigate each of these possibilities are under way.

We will see.