epidemiology

Lingering Post-COVID Vascular Risks

George Burns once opined that “the secret of a good sermon is to have a good beginning and a good ending; and to have the two as close together as possible.” The same might be said for blogs. If so, this is a pretty good blog post.

We have known for some time that patients with COVID-19 are at risk for dangerous blood clots (also called deep vein thrombosis, or DVT), pulmonary embolism, and bleeding. Findings reported this month in the British Medical Journal reveal that this risk continues several months after COVID recovery.

The study compared more than one million people in Sweden who had COVID-19 to a control group of more than 4 million people who did not. The overall risks for each problem were low, but still elevated for up to six months following COVID. According to the report, DVT occurred in 0.04% of patients who had had COVID and in just 0.01% of control patients during the same time. Pulmonary embolism occurred in 0.17% of post-COVID patients and in 0.004% of control patients. And bleeding events occurred in 0.10% of patients who had recovered from COVID, while only 0.04% of control patients had such a problem.

While the risks of blood clots and bleeding were highest in patients whose COVID had been more severe, those who had had mild COVID still showed an elevated risk.

Bottom line: You are not out of the woods after you recover from COVID. Significant problems can arise a few months later.

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Still More Evidence For An Animal Origin Of The Virus

Conspiracy buffs won’t like this, but compelling new evidence presented in three papers, which include photographic and DNA data, has pretty much nailed down the origin of the SARS-CoV-2 virus. It began in a wet market animal not in the lab eight miles away as the conspiracists have conjectured. This new data comes from an international team of scientists which concluded that the coronavirus twice jumped from  caged wild animals into people at the Huanan Seafood Wholesale Market in Wuhan. These data correlate nicely with previous geo-epidemiological data showing the market, not the lab, to be the infection nidus with later infections radiating out from there.

Despite the Chinese’s government denial that live animals were sold in the Wuhan market, the new studies provide photographic evidence of wild animals sitting in stacked cages in the market in late 2019, in or near stalls where scientists found SARS-CoV-2 virus on a number of surfaces, including on cages, carts and machines that process animals after they are slaughtered at the market. This, along with a new genetic analysis pinpoints a specific stall at the market where the virus passed from an animal into people. These data also estimate the time when not just one but two zoonotic spillovers occurred, once in late November or early December and then again few weeks later. This coincides almost exactly with the timing of the outbreak of disease at and around the market.

The two initial infection events involved slightly different versions of the SARS-CoV-2 virus. The fact that they were related is evidence that the virus had spread and mutated in animals in the market before it infected humans.

A leader of two of the studies was U of Arizona professor, Michael Worobey, a viral pandemic sleuth who has been at the forefront of the search for the origins of the bug responsible for the current pandemic. His lead in the research is significant since, back in May, 2021, Worobey, along with 17 other scientists, called for investigation into the lab-leak theory. His latest research overturned that conjecture. This new evidence adds to previous evidence for an animal/market origin of the virus presented earlier in these pages here and here.

Final thought. It is sobering to think how these two simple infection events that occurred in November and December of 2019 in a Chinese market triggered something that has now caused six million deaths and untold misery around the world. And it is not finished with us.

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Another Unexpected Pandemic Consequence: Undiagnosed Cancer

In these pages, your humble bloggeur (that would be me) has written about several unusual consequences of the COVID-19 pandemic. Most of these were on the ironically funny side, such as farmed fish being too large for restaurant plates, rattlesnakes climbing in plane landing gears, and the ketchup packet shortage. But, not all of these odd aftermaths of the pandemic are humorous. The topic of this post is very unfunny.

Lungs

It seems that as healthcare providers were swamped with COVID cases, or were at reduced capacity because staff became ill, or because service slowed in order to prevent CoV-2 spread, many people have missed routine medical care for non-COVID problems. It is feared that this will create a crisis in coming years involving increased diagnosis of cancers that were caught later than usual. As we deal with the fourth wave of COVID-19 caused by the Omicron variant, we are learning that the pandemic dramatically disrupted routine health screenings for cancer and other chronic diseases. Some now predict that the next crisis that could overwhelm the US health system will be a surge in advanced chronic diseases like cancer that went undiagnosed and untreated for too long.

Screenings for several major cancers and new cancer diagnoses fell significantly during 2020, according to a study published in December 2021 in the journal Cancer. This was not because there was less cancer in the world. It was because fewer patients were seeing their doctors.

A co-author of the Cancer study, and who is a professor at the University of Maryland School of Medicine, said that we have never before seen screening rates drop so dramatically in such a short time.

In one case, a Hispanic man in his 40s first noticed rectal bleeding in early 2020 that his doctor said was probably due to hemorrhoids. The man was unable to get a timely colonoscopy to rule out cancer because the local hospitals were overwhelmed with COVID-19 patients, and he also feared catching COVID if he went to a hospital swamped with COVID patients. Eighteen months later, he finally got a colonoscopy, which revealed advanced rectal cancer. Those 18 months likely were the difference between being cured by a simple polyp removal vs dealing with a cancer that had metastasized throughout his body.

At this point, nobody knows how many cases like this are out there. We will find out.  

This patient, as thousands of others like him, had the misfortune to notice symptoms that needed followup amid the biggest disruption of medical care in US history. In 2020, while hospitals curtailed services in order to prepare for the COVID surge, the number of colonoscopies plummeted 93 percent. By the end of the year, there had been 133,231 fewer colonoscopies performed compared to 2019. There also were 62,793 fewer chest CT scans, 49,334 fewer fecal blood tests, and prostate biopsies dropped 25%.

This drop in screenings has created a huge backlog that will take months to clear. A gastroenterologist at a small community hospital in the Middle-of-No-Where, Kansas was recruited by a larger hospital in Kansas City to do nothing but colonoscopies from 7 in the morning to “whenever at night.” They had a backlog of 1000 patients—a certain percentage of whom have cancer already growing in their colons while waiting to be told they had colon cancer. And that backlog begets a fresh one of new patients who also need to be scoped because they just noticed something like rectal bleeding, but will have to wait for those who have already been waiting.

This backlog creates a subtle form of medical rationing. It forces doctors to make hard choices about which patients to prioritize. "Lucky" are the serious patients who are moved to the head of the line. Not so lucky are those whose colonoscopies or mammograms or biopsies are then further delayed.

I would rather deal with rattlesnakes in my plane's landing gear or forgo mustard on my brat (which would be pushing the limit) than delay a needed medical test or procedure. It seems that your humble bloggeur (me again) has been caught in the backlog. I am scheduled to have an enlarged parathyroid gland removed next week, but COVID can still derail that. I won’t be certain that the surgery will happen until the day before I am to be operated on and that depends, in part, on everyone, including me, being COVID-free, and the OR not being diverted for use as a COVID ICU. If it proceeds as scheduled, I will have waited several months since the initial diagnosis for the surgery. An additional routine diagnostic test I need in order to determine how the fractious organ might have affected my bone health was scheduled six months out. Six months for a routine scan?


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.

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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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Has Omicron Rendered Vaccines Ineffective?

Early in the pandemic, when we realized that the CoV-2 virus was quickly producing mutated progeny, some of which were becoming more deadly and transmissible, some (including your humble blogger) warned that viral mutation could feasibly give rise to a variant that ignored immunity to previous iterations of the germ—in other words able to ignore the current vaccines. We have arrived—almost.

The so-called omicron variant partly avoids immunity conferred by the current vaccines (and by prior infection), meaning that we are seeing “break-through” infections in fully and partially  immune people. Popular news sources are running headlines declaring that vaccinated patients with COVID are filling hospital beds, leading many to leap to the conclusion that the vaccines have failed.

But, that is not fully accurate. Many vaccinated people are indeed getting infected with omicron, yet the vaccines are still quite effective, and much better than no vaccine. Let me explain.

First, about two-thirds of Americans are vaccinated—a definite majority of the population. This means that for a hypothetical virus that can fully evade immunity, there are more vaccinated than unvaxed viral “targets” available; meaning more vaccinated than unvaccinated people will be infected. The reality, however, is that the vaccines are still partly protective so that many vaccinated people still catch omicron COVID. Yet, compared to vaxed people, unvaccinated people remain at significantly greater risk of infection, hospitalization, and death. Numbers in my State of Wisconsin, bear this out.

Currently, 69% of the State adult population is vaccinated. According to the latest data* (as of January 15, 2022), out of 100,000 vaccinated people, 1573 caught COVID, 18.5 were hospitalized, and just under 4 died. In contrast, out of 100,000 unvaccinated people, 4,746 got infected, 176 were hospitalized, and 51 died. In other words, many more unvaccinated adults are feeling the effects of COVID, despite representing only 30% of the State population. Clearly, there were breakthrough infections in vaccinated people, but just as clearly, unvaccinated people fared way worse than they would have if they had the shot.

Yet, the headlines persist, proclaiming things like, “Similar numbers of vaccinated and vaccinated people hospitalized for COVID.”   Does this not show that the vaccines are no longer effective? Not at all. Because many more people are vaccinated and partly susceptible to the virus, more and more vaccinated people are showing up with infection, but at a much lower rate than unvaccinated people do. The graphic below illustrates how this works.

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The benefits of the vaccines also are reflected in national and world-wide numbers. The US has one of the lowest vaccination rates among developed countries such as the UK, Canada, Norway, Denmark, etc. And despite omicron’s “milder” nature, which means it kills fewer people but still kills, the COVID death rate in the less vaccinated US is greater than seen in more vaccinated countries, attesting to the efficacy of the shots. Also, new hospital admissions in the US have now reached an all-time high and far exceeding hospitalization rates in better vaccinated countries. Current data from New York State shows that hospitalization among the unvaccinated is 14x higher than among fully vaccinated people.

All of this demonstrates how effective the vaccines remain at preventing infection, hospitalization, and death from omicron-driven COVID. Places with higher vaccination rates, such as the UK and Canada, are not experiencing an increase in base case rates of patients admitted to the ICU or deaths, even with omicron cases skyrocketing. The US is.

Get your Fauci boo boo.

*Note on Wisconsin State data sources: State data mentioned here are from the Wisconsin Department of Health Services, Public Health Madison and Dane County, and the Wisconsin Hospital Association as reported Jan 15, 2022 in the Wisconsin State Journal.


Lions And Tigers And…Deer? Oh My!

First it was bats and humans, then domestic cats and dogs, farmed mink, and big zoo cats; now gorillas, hippos, and wild deer that have been infected by the SARS-CoV-2 (CoV-2 for short) virus. Many of these animals have become ill and several have died of COVID-19, most recently three snow leopards in South Dakota and Nebraska zoos. This is quite a wanton virus.

Of course, before CoV-2 and COVID-19 were known to the world, we knew that bats, humans and a few other animals, notably civets and even camels, were ready hosts of several different strains of “‘rona” viruses. We also knew that domesticated animals are also susceptible to their own coronavirus diseases—in fact veterinary coronavirus vaccines have been in use for years. Humans are known hosts for several coronaviruses, including those that cause the common cold, as well as the viruses that cause SARS, MERS, and now COVID-19. And we know that humans often catch these germs from bats and other intermediate hosts as diverse as civets and camels. After we genetically identified CoV-2 and were able to follow its spread, we quickly noticed that domestic pets also could be infected. This was closely followed with news that seven big cats at the Bronx zoo had become infected, and that mink farms across Europe were hotbeds for CoV-2 spread between humans and the animals and back. In fact, mink farms became such a hotbed of CoV-2 zoonotic spread that a couple of European countries completely shut down mink farming and culled all their animals. Several US states have also sharply curtailed mink farming. PETA probably applauds.

More recently two snow leopards at the Lincoln, NE children’s zoo and one in a zoo in South Dakota died from COVID. The Lincoln zoo also had two infected Sumatran tigers who recovered after being treated with steroids and antibiotics to prevent secondary infections and pneumonia. How the animals were infected is uncertain, but the most likely scenario is that they caught the virus from a caretaker. The problem is, none of the caretakers tested positive for the virus. Bats? Something else?

Since April 2020, when a tiger tested positive at the Bronx Zoo, dozens of other animals in zoos around the world have caught COVID. This month, the Denver Zoo reported the first coronavirus cases in hyenas, and the St. Louis Zoo found eight positive cases among its big cats, including two snow leopards. Abroad, the virus has killed a lion in India and two tiger cubs in Pakistan. Big cats seem especially susceptible since three other snow leopards at the Louisville Zoo were infected last December, and another snow leopard tested positive at the San Diego Zoo in July. The virus doesn’t just infect our fuzzy friends either; two hippos, named Imani and Hermien, at a zoo in Antwerp recently tested positive for COVID-19. Zoo keepers were first alerted to a potential problem when they noticed that the colossi had “runny noses.”  One reckons that a runny nose for a hippo is a big deal. One also wonders who gets to dab that nasal maw in order to test for the virus.

In fact, zoo and domestic animal infections have become so prevalent that an animal COVID vaccine developed by Zoetis, a NJ-based veterinary pharma company and former Pfizer subsidiary, has been authorized by the USDA for experimental use. The Cincinnati Zoo, for one, has vaccinated  80 animals, from giraffes to apes, against COVID.

Deer too. Oh my! It is one thing for zoo animals to acquire COVID—their captivity makes it easy to limit their interaction with other animals and humans to prevent spread of contagions, and they seldom complain that their rights are being infringed when they are quarantined. However, COVID in wild animals is a different story, as we have seen with bats and how easily they transmit the virus to humans. Scientists now have evidence that CoV-2 also readily propagates in white-tailed deer. In fact, the virus is already widespread in cervids across the US, which likely has significant implications for the long-term course of this pandemic.

In September of last year, genetic analysis of the gene that encodes the ACE2 protein (i.e., the viral receptors expressed on many cells in the body) in many different animal species suggested that CoV-2 could easily infect deer (and several other animals too). A survey of white-tailed deer in the Northeast and Midwest found that 40% had antibodies against the CoV-2 virus, indicating prior exposure. Between April and December 2020, veterinarians at Penn State found active CoV-2 infections in ~30% of deer tested across Iowa. Then during the winter COVID surge in humans from Nov. 23, 2020, to Jan. 10 of this year, ~80% of the tested deer were infected. The prevalence of the virus in deer was 50 to 100 times greater than in Iowa residents at the time (and the deer reportedly did not wear face masks). The study, published about two months ago, indicates that white-tailed deer have become a permanent reservoir for CoV-2. While it is not fully understood how the virus entered the deer population, genetic sequence analysis of nearly 100 viral samples found that the variants circulating in deer matched the variants circulating in people. This suggests that deer caught the virus from people multiple times in Iowa alone. How that happens is not known since people usually do not have close contact with live deer. More concerning is whether viral variants arising in deer readily pass back to people.

Bottom line. Clearly, a lot of different animal species can catch Cov-2 and spread it. It is clear that people can spread coronaviruses to pets and other animals, but the FDA says that the reverse, animal-to-human virus transmission, is not common. But, it clearly happens as we have seen with this pandemic, and with many other viruses that cause SARS, MERS, AIDS, Ebola, flu, etc., that spread from animals to humans. The prevalence of CoV-2 infection in so many species of mammals, especially in animals that have close contact with humans, suggests that several animal species, not just bats, can serve as permanent reservoirs for the virus and the jump to humans is something that can happen over and over. This is not unprecedented. It is what we see with influenza, which is carried back and forth between the Northern and Southern hemispheres with migratory birds, in which different flu viruses shuffle their genomes to create the new strains of flu for which we have to vaccinate against each year. This animal reservoir for flu makes it next to impossible to eliminate influenza, and similar animal hosts for CoV-2 likely would make it nigh impossible to eliminate COVID too. I raised this specter some months ago in these pages when reporting that pet dogs and cats can carry the virus. Our furry friends represent a viral reservoir that is in even closer contact with people than bats, deer, and fortunately, hippos and leopards.

We also have to be worried about the CoV-2 virus mutating in the different animal species that harbor and spread it. We know that happens in bats, which makes it almost certain that new strains of the virus will arise in deer and dogs too. We have already seen this on mink farms in the Netherlands and Poland. Farmworkers passed the virus to captive animals where it spread, mutated, and then spilled back into humans. In fact, zoonotic transmission from animals to humans probably happens thousands of times a year. Researchers from the EcoHealth Alliance and from Duke-NUS Medical School in Singapore, estimate that each year many people are newly infected with SARS-related coronaviruses. Many may get sick, but there are many reasons why most of these infections never grow into noticeable outbreaks (for example see my earlier blog post about unusual respiratory infection clusters in China and Los Angeles just before COVID). The researchers also created a detailed map of Asian habitats of 23 bat species known to harbor SARS-related coronaviruses then overlaid it with data on where humans live to create a map of potential infection hot spots. They found that close to 500 million people live in areas where bat-to-human transfer is likely, and this risk is highest in southern China, Vietnam, Cambodia, and Indonesia. Other surveys done before COVID-19 showed that many people in Southeast Asia harbor antibodies against other SARS-related coronaviruses. Blending these data with data on how often people encounter bats and how long antibodies remain in the blood, the researchers calculated that ~400,000 undetected human infections with these viruses occur each year across the region.

That is just for bat-to-human transfer in Southern Asia. It now looks like we will have to also concern ourselves with zoonotic coronavirus transfer from Buddy and Bambi too.

For this reason, researchers are working to develop a universal coronavirus vaccine that will be effective against most viral strains and variants. I will write about this soon. Stay tuned.

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Naturally Immune? You Still Better Get A Vaccine

Over 43 million Americans have reported cases of COVID-19. Many of them likely have some level of immunity that can be quite protective, even without vaccination. Even before vaccines were available, individuals who recovered from COVID-19 had detectable T-cell responses, and reinfections were rare, at least prior to the emergence of the more contagious Delta variant. This is what people refer to colloquially as “natural immunity,” to distinguish it from immunity conferred by vaccination. Some people claim that natural immunity is better and preferable to vaccine immunity and that a history of infection should count as much as being vaccinated when considering vaccine mandates. Is all this true? Well, like what we have seen and heard during the pandemic, a lot of truths have been spread, same with lies and disinformation. The story around natural immunity follows this pattern. Let me try to sort all this out here with a focus on whether previously infected people should consider getting vaccinated.

Natural infection can confer immunity to COVID. Like most viruses, previous infection with SARS-CoV-2 does confer immune protection against future re-exposure to the virus. Several peer-reviewed studies conducted in the early months of the pandemic, before vaccines were available, found that people previously infected were around 80% less likely to test positive for the virus during the next viral surge. These included studies of healthcare workers in the UK, the Danish population, and patients at the Cleveland Clinic, a large health system in Ohio and Florida.

Other data from the UK Office for National Statistics showed that between May and August 2021, a prior infection offered around the same level of protection against the Delta variant as vaccination. (Note that very recent and preliminary observations in South Africa suggest that infection with the new Omicron variant is high in people previously infected with other CoV-2 variants. However, since Omicron is so new and data on it are very sketchy at this time, this review will not further comment on this variant.)

A recent large Israeli study found that people who had been fully vaccinated with two Pfizer shots were 13 times more likely to later get infected with CoV-2 than those who had a prior infection. It also suggested that immunity from infection was longer lasting than that from vaccination. The study also showed that natural immunity plus the vaccine offered protection that was even stronger than either natural or vaccine immunity alone. This is one of the very few studies suggesting that natural immunity is better than vaccine immunity and has not been peer-reviewed. Furthermore, the subsequent rise of Delta since the end of this study confounds the issue a bit since Delta has been shown to be more infectious than the viruses the study subjects were exposed to. 

In the most recent review of the current scientific evidence by the CDC, they concluded that both fully vaccinated and those previously infected with the virus have a low risk of re-infection for at least six months, but that the two forms of immunity appear to have different strengths. Vaccination with mRNA vaccines produced higher concentrations of neutralizing antibodies—the type that prevent the virus from entering cells—than natural infection, although, over time, the antibody levels waned in both groups. However, long lasting immune memory conferred by natural infection appeared to be stronger than that conferred by vaccination.

Over time, immune B cells typically evolve to produce antibodies that better recognize an antigen, and an earlier study published in Nature found that antibodies produced by naturally immune memory B cells continued to evolve at least a year after infection. In contrast, antibodies produced by memory B cells in vaccinated people did not change much over time. This would suggest that over time, antibodies produced by natural immunity gain greater ability to respond to re-infection with the virus than antibodies produced by vaccination. One possible reason for this difference in the evolution of the anti-viral antibodies was that pieces of virus remain in the body for weeks after infection and continue to engage the immune cells, whereas vaccine lipid nanoparticles quickly fade away providing less immune stimulation. 

On the other hand, vaccine immunity might be better. So, as we have seen, a few reports suggest that natural immunity is superior to vaccine immunity. However, more studies suggest the opposite and even show that not everyone who catches COVID-19 will have effective immunity to re-infection. A CDC study reported that 36% of previously infected people did not form any antibodies against the virus. This is in stark contrast to antibody formation reported in 100% of people who received just one dose of an mRNA vaccine. Furthermore, the CDC reported in August that COVID survivors who went unvaxed were more than twice as likely as vaccinated people to get infected again contrasting with the Israeli study I mentioned earlier. Yet another CDC study looking at data from ~190 hospitals in nine states confirmed that unvaccinated people who survived an infection several months earlier were more than five times more likely to get COVID again than vaccinated people.

The reason that natural immunity might not always be effective is because the natural exposure to the virus is highly variable. People naturally infected are exposed to widely different doses of virus via different routes and possibly to different viral strains, all of which conspire to confer different degrees of protection. In contrast, vaccinated people receive standardized doses of the same viral antigen via the same route of exposure, making them more likely to develop a uniform degree of immunity. Researchers found that some people who had been infected had high antibody levels to the virus, while others had low levels, reflecting this variability in natural infection. This was substantiated by a new study from the University of Pittsburgh that also found that in many cases antibody levels from a prior infection are not high enough to protect people from getting sick again. Then, an Oxford study found that both long term T and B cell immune responses were highly variable in naturally immune people. The investigators took monthly samples of blood from infected subjects and measured their T and B cell responses over time. Interestingly, the variability in their responses was clearly identified as early as one-month post infection. Those with the weakest immunity at one month (25% of the subjects) had no detectable antibodies after six months. This contrasts to vaccine immunity, which does fade a bit over six months, but still remains consistently strong months after full vaccination. 

Finally, new evidence from an NIH-supported study from the Fred Hutchinson Cancer Research Center, Seattle showed that antibodies from vaccinated people better recognized the mutated spike proteins from viral variants than antibodies from naturally immune people who had not been vaccinated. In other words, vaccinated people seem better able to respond to mutated spike proteins present in new viral variants.

The bottom line. In sum, while natural immunity can be effective, most evidence shows that vaccines typically give rise to consistently better antibody and long term T and B cell responses.

Having made this point, it is important to further note that a combination of both types of immunity, or so-called hybrid immunity, appears to be stronger than either alone. Researchers found that vaccination of naturally infected people boosted antibody and memory B cells to levels higher than seen in those with just either type of immunity. People with prior COVID-19 who received even one vaccine dose had half the risk of a breakthrough infection than unvaccinated people with prior COVID-19. Another study from researchers at the Icahn School of Medicine in New York found that a single dose of either the Pfizer or Moderna vaccines produced more antibodies in people who had previously had COVID-19 than two vax doses did in those who had never encountered the virus. It also found that people with prior infection report more unpleasant, but not serious side effects from vaccination. Vaccinating previously infected people also elicits important cross-variant neutralizing antibodies that better protect them against the known viral variants. Hybrid immunity also appears to work in the other direction: A study of vaccinated people who were then infected during a July 4 holiday weekend outbreak on Cape Cod found that they produced higher levels of antibodies and T-cells directed against the virus. In sum, vaccination helps those with natural immunity (and everyone they interact with) and vice versa

For these reasons, the CDC now recommends that people who have had COVID-19 be vaccinated because the shots plus natural immunity have been shown to offer better protection than natural immunity alone.


The History Of Vaccine Mandates In The US

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As employers and the President are pushing vaccine mandates because too many have refused them, voices are crying out for their perceived rights saying “my body my choice.” They do not like their bosses or the government telling them to get vaccinated. This is a clash between individual rights and public health measures designed to save lives and to protect the larger community. Who gets to make the key decisions? How far can the government and employers go? Do individual rights trump community safety?

On Sept. 9, Biden announced the most sweeping vaccine requirements in American history, ordering that businesses with 100 or more employees ensure that all their workers are either vaccinated or get tested weekly for the coronavirus. The new rules also require vaccinations for federal workers and for federal contractors, as well as for workers at healthcare facilities that receive funding from Medicare and Medicaid. This will affect about 100 million people.

The authority for these government mandates, claims Biden, is a 1970 federal statute that gives the Secretary of Labor authority to issue a six month Emergency Temporary Standard (ETS) to protect workers from “grave danger from exposure to substances or agents determined to be toxic or physically harmful.” His move has triggered a political and legal battle, with many Republican governors vowing to fight the mandates in court. The mandates raise several new questions regarding this vague statute: Is a virus a “…toxic or physically harmful substance?” Does COVID-19 present a “grave danger?” Has the executive branch exceeded its authority in offering a solution to a problem previously reserved to the states? Do these mandates violate the 14th Amendment by depriving workers of their personal liberties? It is important to note that Biden’s mandates do not actually make vaccines compulsory: The government may levy a fine or forbid a child from attending school, but no American will be forced to get an unwanted jab. This has not always been the case.

There are historical precedents for vaccine mandates and even for forced vaccination.

In February 1991, five Philadelphia children died from measles, a disease that was mostly eradicated in the US, due to vaccination. Measles once sickened millions of kids, each year hospitalizing ~50,000 and killing close to 500 before a successful vaccine was developed in 1963. After that, cases dropped dramatically as all states mandated measles shots for school children. Vaccine hesitancy and resistance were rare because people saw the tangible success of the measles vaccine.

But, in Philadelphia that winter of 1991, the serious cases of measles came from a single source, a church cult that rejected “…all means of healing apart from God’s way.” Church members took no medicines, owned no thermometers, and saw no doctors. Rejecting all birth control, they raised large families in close quarters, a recipe for the measles epidemic, which they cooked. Trying to contain the threat to the rest of the city, officials worked through the courts to gain access to the homes of the congregants and received the authority to vaccinate the children against the wishes of their parents. In this public health emergency, defending the parents’ anti-vax actions was close to impossible. Even the ACLU took a pass.

Vaccine mandates even appeared during the Revolutionary War. George Washington mandated that all his troops be immunized against smallpox, even against their will. He described smallpox to Virginia’s Governor Patrick Henry as “more destructive to an Army in a Natural Way, than the Enemy’s Sword.” As I wrote earlier in these pages, smallpox had doomed the Colonial Army’s assault on Quebec in 1775, and it threatened Washington’s main force. Washington’s mandate proved a brilliant gambit and smallpox largely disappeared from the ranks. Some historians point to the mandate as a major factor in winning the war against the Brits.

During that war, smallpox vaccination entailed a primitive vaccination procedure known as variolation. That involved opening a lesion from an infected person and scraping its contents into the arm of a recipient. It was effective, but the vaccinated person became quite ill for a couple of weeks, and about 3% of them died from the pox. Later, in 1796, the English scientist Edward Jenner discovered a much safer method of immunization using cowpox, a virus similar to smallpox that did not cause significant disease in people. But the new smallpox vaccine got a mixed reception in the US as some resisted it for reasons of personal safety based on the variolation experience. They rationalized, “what good could possibly come from polluting the body with dangerous foreign matter?” Or, “Why challenge the plans of the Creator?” Still, Jenner’s vaccine was a clear improvement over variolation and drove a steady decline in smallpox outbreaks throughout the 19th century. States began passing laws mandating smallpox vaccinations for school children, and some forcibly vaccinated prisoners, paupers, and orphans.

In 1905, the issue of vaccine mandates reached the Supreme Court in the seminal case of Jacobson v. Massachusetts. Henning Jacobson, a Lutheran pastor in Cambridge had defied a city ordinance requiring smallpox vaccinations during an outbreak. He refused to pay a $5 fine so he was arrested. Jacobson posited that “healthy and law-abiding” people like himself (even though he was disobeying the law at the time) posed a minimal danger to the community. He argued that even if his refusal to be vaccinated led to him spreading the smallpox virus, the only victims would be others “who failed or refused to be vaccinated.” In other words, he reasoned that it would be ok to not get the vax because the vaxed would be safe, but wholly ignored the rights to safety of those who were not vaxed. 

It is an argument that is repeated today about the CoV-2 vax. Using modern science that was not available in the early 20th century, experts have repeatedly refuted this argument, explaining that many people who want the vax cannot be fully vaccinated because they are immunocompromised, or allergic to the vaccine’s contents, or do not have access to the vaccine. Also, we now know that the more RNA viruses, like the coronavirus, are allowed to spread, the greater the chance more deadly variants can appear. Jacobson’s contention that the decision to vaccinate solely belongs to the individual, not to the state, employers, or to medical authorities remains a central tenant of today's anti-vaxers.

The Supreme Court disagreed with Jacobson. The majority opinion, written by Justice John Marshall Harlan, asserted that “the liberty secured by the Constitution does not import an absolute right in each person to be at all times, and in all circumstances, wholly freed from restraint.” Rather, he argued, the Constitution rests upon “the fundamental principle of the social compact…that all shall be governed by certain laws for the protection, safety, prosperity and happiness of the people, and not for the profit, honor or private interests of any one man, family or class of men.” Jacobson had not only broken the law, the court suggested he also had violated the principle upon which a well-ordered society depends. We are not wholly independent the court ruled. The greater good of the community can trump individual rights.

Using Jacobson as precedent, the Supreme Court in 1922, upheld a local ordinance in San Antonio requiring proof of smallpox vaccination for people entering “public schools or other places of education.”  

Later, during World War II, the US military made vaccines mandatory for a host of diseases, such as typhoid, yellow fever and tetanus, and it still mandates certain vaccines for troops in certain deployments. Soon after the war very successful vaccines were developed against several childhood diseases like polio, measles, mumps and chickenpox. Guided by the Supreme Court’s ruling in Jacobson, all 50 states put laws on the books mandating many of these vaccinations for school children. Even today, many school districts and colleges mandate certain vaccines for students and staff. Hospitals, too, often mandate certain vaccines for their staff. Until lately, vaccine mandates have not generated much angst and anger.

Why is this? Perhaps vaccines have done their job too well: Many of them have erased the tragic evidence of why they were needed in the first place. The world no longer deals with small pox, thanks to the vaccine. Almost no one in this country has seen someone ravaged by polio, or a child hospitalized with measles, or who lost his hearing due to chicken pox, all thanks to vaccines. Yet, now with COVID-19, anti-vaccine anxieties have found their way into the political mainstream, especially among conservatives. An estimated 80 million American adults remain unvaccinated against COVID and represent potential factories for producing the next deadly coronavirus variant, which is very preventable.

As I have addressed before in these pages, many factors fuel resistance to the life-saving shots, including doubts about their quick development and their possible long-term effects. But a growing distrust of professional expertise, including medical science, has also played a role, which is unwarranted. Who are you going to believe, a medical scientist like me with nothing to gain in the debate (except the safety of my friends, family, and self), or someone who read a web post from folks who are selling nostrums they claim will protect you, like Dr. Steve Hotze, or from one of America’s Frontline Doctors whose web site claimed that gynecological problems were caused by having sex with demons? Do you jump on the side of those who tout that their individual freedoms have been abridged, but who do not consider the freedoms from disease of the greater community, and whom the courts already have decided against?

Almost 300 years ago, Benjamin Franklin struggled over whether to have his sons variolated against smallpox. In his “Autobiography,” he worried that well-meaning people were tragically misjudging the calculus between the risks and benefits of the procedure, as he had once done, with a tragic result. He wrote, “In 1736, I lost one of my sons, a fine boy of four years old, by the smallpox….I long regretted bitterly and still regret that I had not given it to him by inoculation. This I mention for the sake of the parents who omit that operation, on the supposition that they should never forgive themselves if a child died under it; my example showing that the regret may be the same either way, and that, therefore, the safer should be chosen.”


Unvaccinated People Are 11 Times More Likely To Die Of COVID-19

People who were not fully vaccinated this spring and summer were ~10 times more likely to be hospitalized, and 11 times more likely to die of COVID-19, than those who were fully vaccinated, according to one of three major studies published mid-September by the CDC.

That study did not distinguish between which vaccine the vaccinated cohort received. But, a second study compared the different vaccines and found that the Moderna vax was somewhat more effective in preventing hospitalizations than the Pfizer and J&J vaccines. This assessment was based on the largest US study to date of the real-world effectiveness of all three vaccines, involving about 32,000 patients seen in hospitals, emergency departments and urgent-care clinics across nine states from June through early August. While the three vaccines were collectively 86 percent effective in preventing hospitalization, protection was higher among Moderna vaccine recipients (95 percent) than among those who got the Pfizer (80 percent) or J&J vaccines (60 percent). That finding echoes a smaller study by the Mayo Clinic Health System in August, which showed the Moderna vaccine to be more effective than the Pfizer vax at preventing infections from the Delta variant.

Vaccine effectiveness against infection dropped from 90 percent last Spring, when Delta had not yet gained significant traction, to less than 80 percent from mid-June to mid-July, when Delta began out-competing other viral variants. Importantly, effectiveness against hospitalization and death showed barely any decline during the entire period. Thus, all vaccines remain quite effective and useful in protecting against illness.

Get one!

Why there is a difference in preventing infection between the Pfizer and Moderna mRNA vaccines was discussed earlier in these pages.


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.