vaccines

The Next Pandemic Is Here

Who ya gonna call?  --“Ghostbusters”

We seem to have mostly weathered two-plus years of a pandemic like the world has not seen in our lifetimes. It raced across the globe killing and maiming people, and overwhelming health care capabilities. Sure, we have read the history about the black plague, small pox, and the Spanish flu pandemics, but vicarious experience through books and film is no substitute for first-hand experience. We now have that experience. It was sobering to see the novel SARS-CoV-2 virus ravage country after country while medical experts played a desperate game of catch-up to learn how to retard the spread of a brand new virus and how to treat the brand new COVID-19 disease it spawned. It was sobering seeing and hearing about people we know get very ill and sometimes die, and sobering reading the statistics of millions of deaths that occurred worldwide.

While most of us today have not seen such a pandemic wild-fire before, we have seen other, more smoldering pandemics that do not spread as fast. HIV is a good example. It too is a world-wide disease that, for many years was a death sentence for those who were infected. Now it is a well-managed chronic disease, thanks to medical science.

The world was not as frantic over HIV and AIDS as we were over CoV-2 and COVID. The reasons for this are probably two-fold: First, it was quickly recognized that AIDS was largely limited to homosexual men and IV drug users and, therefore, was not an eminent threat to most of us. It was not necessary to quarantine, mask up, and shut down businesses and schools in order to prevent catching the “gay disease.” Second, despite the world-wide spread of AIDS, it is not easy to catch. You must be in very intimate contact with an infected person to catch it—it is not caught by simply breathing the same air as an infected person like COVID is. Clearly, not all pandemics are created equal. Some smolder like AIDS, others fulminate like COVID. What will our next pandemic be like?

As the global population grows, as the climate changes, as humans push into spaces occupied by wild animals, and as we continue enjoying our ever increasing global connectedness, future pandemics become more likely. We are not guaranteed the luxury of facing just one a century, or even one at a time. As greatly encouraging, even exciting as it was to watch the post-molecular BioX science, as I have called it, roar into life to produce several effective and novel anti-CoV-2 vaccines in record time, there is no guarantee BioX can save us next time.

Well, the “next pandemic” already is upon us and BioX is struggling to deal with it. This pandemic is not as volatile as COVID or the Spanish flu. In fact, compared to COVID, it is a “slow mo’” pandemic, more like AIDS. But, it promises to be more difficult than COVID, even for BioX, to mitigate. It currently kills about 700,000 people annually around the world, but threatens to kill 10 million people a year by 2050 (in contrast, COVID killed ~6 million around the world in 2.5 years).

The problem

 In March 1942, Anne Miller of New Haven, Connecticut, was near death. A bacterial infection had made its way into her bloodstream, which was a death sentence at that time. Desperate to save her, doctors administered an experimental drug called penicillin, which Alexander Fleming accidentally discovered 14 years earlier. In just hours, she recovered, becoming the first person to ever be saved by an antibiotic. Rather than dying in her thirties, Mrs. Miller lived to be 90 years old and Fleming went on to win the Nobel Prize for his inadvertent discovery.

Today, decades later, germs like the one that infected Mrs. Miller, but easily eradicated with antibiotics, are increasingly becoming resistant to penicillin and the many other antibiotics that have since been developed. There is a very good chance that right now, you have such a “superbug” in or on your body—a resistant germ that, given the opportunity could enthusiastically sicken you leaving medical people at a loss on how to treat you. You would be at the mercy of the bug just as all patients with a microbial infection were before Mrs. Miller.

We are not talking about a new, exotic germ like CoV-2 suddenly appearing and ravishing the world. The antimicrobial resistance crisis stems from the simple fact that new antibiotic development cannot keep pace with the rate that common microbes become resistant to antibiotics. This very slowly growing pandemic we are now in involves run-of-the-mill pathogens, bacteria and fungi that have caused disease since humans first dragged their knuckles on the earth. These are bugs which we had well controlled with antibacterial and antifungal drugs, but there is a very definite trend toward these germs becoming resistant to ALL known antimicrobial medicines we have. Infection with multidrug resistant pathogens is the slow moving pandemic that already is among us but that is growing at a logarithmic rate.

Since multi-drug-resistant infections do not respond to our antibiotics, treatment increasingly involves surgically removing an infected organ. For example, in the case of drug-resistant Clostridioides difficile (aka, “C-diff) colitis, an emergency colectomy is performed when patients no longer respond to antibiotic therapy. CDC data show C-diff infections occur in half a million patients each year, and at least 29,000 die within one month of initial diagnosis. Up to 30% of patients with severe C-diff colitis develop sepsis require emergency surgery, and still their mortality remains high.

As of 2019, about 18 drug resistant pathogens affected >3 million people in the US, causing 48,000 deaths. These bugs cause pneumonia, septic shock, various GI problems, STDs, urinary tract infections, typhoid fever, TB, and infection with the so-called “flesh eating bacteria.” Compared to COVID, this has received relatively little attention in the popular press, but has been a frequent topic in medical lectures and conferences for the last 20 or more years. These infectious disease lectures tend to scare the bejeebers out my colleagues and me. This smoldering pandemic is that serious.

And it is not just antibiotic-resistant bacteria we have to worry about. Certain fungi, especially of the Candida genus, cause various serious ailments in people. Recently, for the first time, the CDC reported five unrelated cases (two in DC and three in Texas) of people infected with fungi that showed “de novo” resistance to all drugs. Usually, drug resistant fungi only appear after infected patients have been treated with antifungals. But, the patients in these five de novo cases had no prior exposure to antifungal drugs. The fungi were already drug-resistant when they infected the patients; they were picked up from the environment already resistant to our medicines.

Antibiotic resistance is now one of the biggest threats to global health. It occurs naturally in naturally occurring pathogens, but is accelerated by overuse of antibiotics in humans and animals, especially farm animals. What happens is that upon treatment with an antibiotic, a single infectious bug out of a population of millions or billions fortuitously mutates and becomes resistant to the antibiotic. The antibiotic then kills off all the non-resistant population, including beneficial bacteria, opening the door for the drug-resistant pathogen to take over. This resistance can occur via many different mechanisms. The bacteria or fungal cell can stop taking up the drug, it can spit out the drug if it is taken up, it can neutralize the drug once it takes it up, or it can change its internal machinery so that it no longer responds to the drug. This problem can be further exacerbated since bacteria and fungi can pass along their mutations by sharing mobile genetic material with their progeny and even with other bugs in their immediate environment that have never been exposed to the antibiotic. They can even pass along this DNA to microbes of different species. Bacteria can also pick up DNA remnants left over from dead germs. Thus, DNA that confers resistance to anti-microbial drugs can spread to the environment even in treated human and animal waste contaminating lakes and streams and ground water.

Currently, the major problem with drug resistant infections occurs in in-patient clinical settings—perhaps you have seen the heightened infection control efforts (gowns, gloves, masks, and isolation) in hospitals designed to prevent the spread of untreatable pathogens. People receiving health care, especially those with weakened immune systems, are at higher risk for getting an infection. Routine procedures, such as bladder catheterization or kidney dialysis are common ways to introduce drug resistant germs into clinical patients. But, infection can happen in any surgical or invasive procedure. Treatment of diabetes, cancer, and organ transplantation can weaken a person’s immune system making them even more susceptible for infections that either are, or that can become drug resistant.

But, antibiotic infections can also occur in the community outside of clinical settings. There is the case of Mike who needed a month long hospital stay for kidney failure after bringing home a new puppy from which he caught a multidrug-resistant Campylobacter infection. He was one of 113 people across 17 states who was part of an outbreak linked to pet store puppies. He recovered after surgery to remove a dead section of his stomach.

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The NIH Hospital Experience. About 10 years ago, the NIH Clinical Center in Bethesda was hit with an epidemic of drug resistant infections that killed a number of patients in just a few months. It was such an intractable problem that NIH finally had to gas rooms with a disinfectant, rip out plumbing, and build a wall to isolate infected patients. Still, over a period of six months it reached 17 patients, 11 of whom died. In this case, the bug was Klebsiella pneumoniae, which arrived in June 2011 with a 43-year-old female lung transplant patient who had just transferred from New York City. NIH nurses noted something startling in her chart: She was carrying an antibiotic-resistant infection.

Desperately trying to contain the superbug before it could spread, the NIH staff quickly isolated the woman in the ICU. Staff members donned disposable gowns and gloves before entering her room and her nurses cared for no other patients. After a month, the patient was discharged and the staff believed that their containment measures had worked. There were no signs that the bacteria had spread. But a few weeks later, they were shocked when a second patient tested positive for resistant Klebsiella. A third and fourth soon followed and all these patients died.

This pattern was baffling since, if the bug had not been cleared, it should have reappeared sooner. Even though it was the same type of bacteria, K. pneumoniae, perhaps it had spontaneously arisen anew in the other three patients. But by reading the genomes of the bacteria isolated from each patient, including the NYC transfer, scientists at NIH’s National Human Genome Research Institute saw that the bacteria in the subsequent patients came from the New York patient.

That meant two unsettling things: The bacteria lingered for weeks unnoticed in the hospital environment; and the hospital’s infection control measures for the New York patient failed. A further search for the bacteria found it on a ventilator that had been bleached twice. They also found it in a sink drain in a patient’s room, so they tore out all the plumbing. Yet, it began popping up it in more patients, at a rate of about one per week.

As hospital staff desperately raced to stanch the outbreak, they also struggled to treat the infected patients. Out of desperation, doctors battling the deadly, drug-resistant superbug turned to colistin, an antibiotic of last resort. It is not a new drug, having been discovered in 1949 in a beaker of fermenting bacteria in Japan. It had quickly fallen out of favor then since it causes significant kidney damage. The fact that the doctors resorted to such an old, dangerous drug highlights the lack of new antibiotics coming out of the pharmaceutical pipeline even in the face of a global epidemic of hospital-acquired bugs that quickly grow resistant to our toughest drugs.

While colistin defeated the superbug in a few patients, in at least four, the bacteria evolved so rapidly it outran colistin, too. Those four died. This was when the wall was built and all new Klebsiella-positive patients were moved into a new isolation unit behind the wall. Blood pressure cuffs and other normally reusable gear were tossed after one use. Clinical monitors were hired to follow doctors and nurses around to ensure that they were donning gowns, gloves and masks, and scrubbing their hands after seeing each patient.

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Among the most concerning mutating bacteria are carbapenem-resistant Enterobacteriaceae (CRE). Enterobacteriaceae are a large family of more than 70 bacteria that includes the common E. coli, that normally live in the digestive system and help digest food. But, if conditions allow the bacteria to leave the digestive system, they can cause serious disease that needs to be treated with antibiotics. They too can quickly develop resistance to front-line drugs and become a serious problem.  Carbapenem is an antibiotic "drug of last resort" used to treat disease caused by bacteria resistant to other front line antibiotics. Therefore, CRE are resistant to all or nearly all antibiotics and kill up to half the >13,000 patients who get bloodstream infections from them. The CDC first detected this type of antibiotic-resistant bacteria in 2000. Since then, it has been reported in 41 states. In the 10 years between 2001 and 2011, the percentage of Enterobacteriaceae resistant to antibiotics increased almost fourfold according to the CDC. Recently, the CDC tracked one type of CRE from a single health-care facility to facilities in at least 42 states.

The cause

The antimicrobial resistance crisis stems from the simple fact that new antibiotic development cannot keep pace with the rate that bacteria become resistant to antibiotics. Between 1945 and 1968, drug companies invented 13 new categories of antibiotics. Between 1968 and today, just two new categories of antibiotics have arrived. In 1980, the FDA approved 4-5 new antibiotics a year, but now only about 1-2 new drugs are submitted annually for approval. Hence, the solution appears quite simple: Develop more novel antibiotics. However, this is quite complicated since BioX science, which led to the rapid development of the novel mRNA anti-COVID vaccines, has not quite caught up to novel antibiotic development. There are two general reasons for this. First, finding a drug that disrupts the metabolism of bacteria or fungi, but that does not interfere with mammalian biochemical pathways is a difficult and narrow path. Second, so far, the market for novel antibiotics has been comparatively small, meaning that the profit incentive for pharma companies has not been large compared to that for so-called lifestyle medications. While a new antibiotic may bring in a billion dollars over its lifetime, a drug for heart disease may net $10 billion. Drugs to treat depression and erectile dysfunction are typically taken for years making them much more profitable than antibiotics that are used short-term.

Development of bact resistance

Even if we could develop new antibiotics faster, their overuse is the primary driver of antibiotic resistance. According to the CDC, in 2018 seven antibiotic prescriptions were written for every 10 Americans. Of these, one-third were unnecessary, and very often were prescribed for viral illnesses that do not respond to antibiotics. Clinicians writing these prescriptions argue that the antibiotic can help prevent the primary viral infection from leading to a secondary bacterial infection. In other words, many antibiotics are prescribed for prophylaxis rather than treatment.

Time to resistance

The number of new antibiotics that the FDA approves annually has slowed to a trickle, while the rate of bacterial mutation has grown exponentially. It used to take 21 years on average for bacteria to become resistant when antibiotics were first used. Now it takes just 1 year for bacteria to develop drug resistance because antibiotics are so readily prescribed and used. Today, the CDC lists 18 different types of antibiotic-resistant bacteria, five of which are classified as urgent threats to human health.

Physician-prescribed antibiotics, however, are not the only, or even main, source of our antibiotic resistance crisis. In the U.S., 70%-80% of all antibiotics are given to animals, especially farm animals destined for human consumption.  Drug-resistant pathogens from farm animals can spread to the environment providing a gateway through which drug resistant germs can quickly spread across our communities, food supply, and even our soil and water around the world.

Surprisingly, antibiotic use is even rampant in salmon and other fish farms, which is especially concerning, considering that 90% of fresh salmon eaten in the U.S. comes from such farms. Antibiotic-resistant infections also affect petting zoo animals, which can then transfer the germs to people.

The solution

Antibiotics clearly have been miracle medicines, saving countless lives; however, anytime they are used, they drive the development of antibiotic resistant pathogens that ultimately defeat their purpose.  Developing new antimicrobial drugs to counter the growing resistance to current drugs is not working; it is not keeping pace with the appearance of new antibiotic resistant germs. Without drastic changes in the science and economics behind antibiotic development and business, this will only be a partial solution to the growing pandemic. However, what we can do now is resort to low-tech, less expensive, and more innovative mitigation measures. These include alternative prevention steps such as more judicious use of antibiotics and increased use of isolation and sanitation measures (where have we heard this before?). Isolation and sanitation defenses against infectious diseases have been part of our disease fighting repertoire since the earliest awareness that contagions can spread through communities. It is an ancient remedy, but still the most effective way to protect ourselves against contagious diseases worldwide. Between 2013-2019, these mitigation measures led to an 18% reduction in US deaths from drug resistant infections. It always is better to prevent than treat.

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Alternative medical treatment and prevention options.  Besides the obvious masks, gloves, sanitation, and quarantine measures, there are other alternative medical (i.e., non-antibiotic) options that can be used to prevent and control drug resistant infection. In fact, these methods are often preferable to using antibiotics, which also deplete the microbiome of “good bacteria” that are critical for good health. These options include vaccines, therapeutic antibodies, and bacteriophages.

From 2000 to 2016, members of the WHO increased the use of the pneumococcal vaccine around the world, thereby decreasing antibiotic use which slowed the development of antibiotic resistant S. pneumoniae saving ~250,000 children from death. Pneumonia caused by secondary infection with other bacteria is a leading cause of complications and death in patients who get the flu. Therefore, the influenza vaccines also are effective tools to decrease the risk of drug-resistant bacterial pneumonias by preventing viral influenza. Since patients with COVID can also develop secondary complications from bacterial pneumonia, COVID vaccination now is another important weapon in the arsenal to prevent the development of antibiotic resistant bacterial lung infection.  

In recent years, healthcare providers also have been increasingly using therapeutic antibodies to treat viral and bacterial infection. For example, antibody therapy is often used to treat recurrent C-diff GI infections, and antibodies to prevent and treat bacterial associated pneumonia also are being developed. So far, we have not seen bacteria develop resistance to antibodies.

Finally, a different and very novel approach to dealing with untreatable bacterial infection has recently taken advantage of bacteriophages, which are viruses that can specifically infect and kill bacteria. There are a few cases in which phage therapy has been used to cure people dying of multidrug-resistant bacterial infections.  According to Pew Charitable Trusts, as of June 2019, 29 non-antibiotic products like therapeutic antibodies and phages were in clinical development and seven were in Phase 3 clinical trials. 

Perhaps BioX is indeed coming to rescue us from the growing pandemic of drug-resistant pathogens.

Notes: 1) By way of disclaimer, your correspondent has consulted for a biotech company that engages in “big genome” research to search for novel antibiotic molecules produced by everyday bacteria and fungi that grow in the soil under your feet. Something like this could be part of the future of novel antibiotic development. 2) In order to have blog updates delivered to your email, see the simple Subscription Instructions here. Remember, you can easily unsubscribe when you want. But, you can’t beat the price.


COVID More Deadly Than Flu For Kids

In the US, nearly six times more kids and teens died from COVID in one year than did from the flu, according to a new analysis of pediatric mortality data. According to CDC data, childhood flu deaths have ranged from 39 to 199 per year since 2004. Meanwhile, in 2021 alone, more than 600 children died from Covid-19, according to an analysis done by researchers at the Harvard University Medical School and at Brigham and Women’s Hospital in Boston.  The analysis used data from the CDC to compare COVID deaths during the pandemic to flu deaths over the last decade (see figure below).

Of the known respiratory viruses, only CoV-2 has ever killed more than 100 US kids in a single month since the middle of the 20th century. Much of that is because we have long had vaccines for other viruses that cause human respiratory disease, but have yet to widely vaccinate children against COVID-19. Hopefully, new vaccines will also render COVID less deadly for kids like vaccines have done for several other respiratory diseases.

Throughout the pandemic, some have argued that COVID poses little health risk to kids aside from a few days of sniffles. Though kids often experience less-severe symptoms than adults, COVID is still a very real risk. An estimated half a million kids now deal with long COVID, a number that experts say is likely an undercount because its myriad symptoms make it tricky to diagnose.

Mortality in kids


A Single Gene Doubles Risk Of COVID Death

“Nothing shocks me. I’m a scientist.” —Indiana Jones

British scientists recently identified an allele, or a version of a gene, that portends lung failure and death in COVID-19 patients. Research recently published in the journal Nature Genetics, found that a poorly studied gene expressed in lungs, designated LZTFL1, has a variant form that does not differ in its coding sequence. That is, the different alleles of the gene express the same protein sequence. They do differ, however, in their non-coding sequences that regulate expression of the gene. When expressed, the gene product prevents cells lining airways and the lungs from responding properly to the CoV-2 virus. The lining of the lung essentially transforms into less specialized cells which affects their normal function.

Previous work had identified a stretch of DNA on human chromosome 3 that doubled the risk of death from COVID. Using an artificial intelligence algorithm to analyze millions of genetic sequences from hundreds of cell types from all parts of the body, the Oxford University Howard Hughes research team honed in on the lung-specific genetic off-on switch. This is another example of what I previously labeled "BioX," the new frontier of bioscience, or post-molecular biology science.

Importantly, the variant allele that augurs a worse lung response to infection does not affect the immune system. Therefore, the it is probable that vaccination remains the best way to protect these at-risk patients. Finding this new allele could also lead to novel therapies to target the pathway affected by this genetic variant to provide targeted treatment for at-risk populations.

The troublesome variant is mostly found in people of South Asian ancestry—some 60% of whom carry the allele—which partly explains the severe devastation from COVID seen in the Indian subcontinent. In contrast, 15% of those with European ancestry and 2% of Afro-Caribbean people carry the risky allele.

It will be interesting to see if this lung-specific gene also affects the course of other respiratory infectious diseases.

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Why Don’t The COVID Vaccines Last Longer?

The FDA just authorized a second booster shot of the Pfizer-BioNTech and Moderna coronavirus vaccines for people over 50 and the CDC has approved it. A second booster has already been approved in the U.K., Sweden, Israel and Denmark.

Why do we need a second booster only months after the first booster, which came only months after most of us received two jabs of either the Pfizer-BioNTech or Moderna mRNA vaccines? Are the vaccines not very good? After all, we get small pox or measles shots that last a lifetime. Others, like the vax for tetanus, last for ~10 years. Why can’t we get a more durable coronavirus vaccine?

The answer is complicated and largely rooted in both viral biology and vaccine immunology.

Viral biology. The simplest answer is that viral mutation can change the molecules the vaccine immune response is trained to recognize, causing vax immunity to decay as viruses mutate. The coronavirus vaccines are directed against the spike protein expressed on the original CoV-2 that first appeared in Wuhan, but that ancestral bug has spawned mutated progeny that look a bit different to the immune system. In other words, viral variants created by “antigenic drift” become less recognizable to the immune system. That is why the vaccines are somewhat less effective against the Omicron variant that carries numerous point mutations in its spike protein. The current vaccines are still pretty effective against current viral variants, but continued antigenic drift along with the selection of variants that can better avoid vaccine immunity will likely require new vaccines in the future.

So, why do we need new flu vaccines every year, and need frequent CoV-2 vaccines, but we don’t similarly need new measles vaccines? Measles, mumps, flu, COVID, and other diseases are caused by viruses, but the different viruses behave quite differently. Viruses carry relatively little genetic material that tends to mutate as they replicate and spread. Some viruses, like flu, also have a “segmented genome” meaning that their genetic material is carried on several separate genetic molecules, making it easy to shuffle their genomes like a deck of cards when different flu strains infect the same animal. Other pathogens carry all their genetic material on a single DNA or RNA molecule making such gene shuffling between strains less likely, but it still happens. Also, the mutation rate of a pathogen’s genome is a function of its replication rate; hence, each time a bug copies its genome, small random errors are inserted into its genetic code. The more the bug replicates, the more mutations will accumulate in its genome and the faster replicating bugs will more rapidly create new variants. Thus, the measles virus is pretty stable since it does not replicate as much as a coronavirus or a flu virus, so it is not surprising that vaccine immunity to measles is much more durable. Smallpox and polioviruses also have relatively low replication rates and vaccine immunity to them also is long-lasting. In contrast, flu and coronaviruses replicate rapidly and pass back and forth between humans and animals. This means that they mutate rapidly and need frequent vaccine updates.

Other vaccines, such as the TB vax, target bacteria not viruses. Bacteria carry larger genomes that are not so changeable, so anti-bacteria vaccines also are pretty long-lasting compared to many anti-viral vaccines.

Yet other vaccines, such as those against tetanus, diphtheria, and pertussis do not even target the pathogen at all, but target toxins produced by the bugs. Vaccinated people produce antibodies that neutralize the toxins and this prevents disease. These vaccines do not forestall infection, they simply prevent the ill effects of the pathogen. Therefore, for these toxoid vaccines, there is no immunological selective pressure to select pathogen variants that can avoid vax immunity. Vaccines against these toxins also tend to be among the longest-lived vaccines.

Vaccine immunology. Vaccines aim to mimic natural immunity we develop to infection with pathogens. By exposing the body to harmless imitations of a pathogen, vaccines create an immune response and immune memory against pathogens, while avoiding the disease caused by the bugs. When an infection does occur in a vaccinated person, a rapid and robust immune response is mounted, first with B-cell generated antibodies that latch onto the invaders and prevent them from spreading and causing illness. Then T-cells secret cytokines that further ramp up the inflammatory response, and other T cells attack pathogen-infected cells. As explained earlier in these pages, antibody responses tend to linger only a few weeks to a few months and then gradually decay. This is good; otherwise your blood serum would be like syrup from all the antibodies against all foreign things you encountered over your lifetime. While antibodies circulating in your blood are good for quickly attacking infections shortly after infection, they do not confer long-term immunity. What confers long-term protection is what are called memory cells. These are a relatively few T and B cells that go dormant after fighting an initial infection or responding to a vaccine, but hang around awaiting a new infection to signal them to quickly roar back to life and mount a vigorous response against their cognate pathogen. This secondary response to a previously seen pathogen is much faster and usually nips the bug in the bud so you don’t even know you were infected.

When we hear that CoV-2 immunity decays only a few months after vaccination, the reports usually refer to declining levels of anti-CoV-2 antibodies, which happens naturally. Such announcements do not take into account your immune memory, which is harder to measure, but which is a better metric of your long term immunity. The problem also is that we simply have not had enough time with the vaccines to know how long their immune memory persists. It seems relevant that a study published in July 2020 reported that people who were infected with SARS in 2003 maintained robust T cell immunity 17 years later. So far, indications are that even though antibody levels fall over time, immunological memory after vaccination also remains robust. This is seen by the continued protection from serious disease and death in vaccinated people with low antibody levels. The vaccines and the immune memory they stimulate are working. How long that memory persists is unknown. Time will tell.

So why are we getting the booster shots? In the face of a raging pandemic caused by a novel pathogen, the cautious approach is to keep antibody levels at a protective level in vaccinated people until we better understand the extent of long-term protection brought on by our immune memory. The boosters, therefore, represent a cautious approach to maintain an effective antibody defense during these still early months of a novel pandemic. We likely will reach a time where world-wide immunity from vaccination and natural infection will give us baseline protection that will render COVID-19 mostly a bothersome disease rather than a life threatening infection. Until then, the boosters are a good idea to help us maintain an effective antibody defense against serious disease.

The natural pathology of measles is instructive here. Even though antibody levels typically decline after most immunizations, antibodies produced after a measles vaccine persist for many years. This happens with some other, but not all, vaccines too, but why? In countries where the measles virus is endemic, repeated infection of vaccinated people keeps the antibody immune response in continual high gear. That is not the case with the flu virus which changes rapidly and bypasses last years shot. Interestingly, measles has been eradicated from the US and Western Europe, so vaccinated people are not continually exposed and re-exposed to the virus and, unlike for those who live in endemic areas, our anti-measles antibody levels decline. Therefore, our long-term protection against the virus is due to our immune memory and not due to antibody levels.

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Updated: Over 65? Roll Up Your Sleeve Again

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The Washington Post just reported that Pfizer and its partner-in-vax, BioNTech, plan to seek emergency authorization for a second CoV-2 booster for those of us 65 and older (you know who you are). It is intended to beef up immunity that wanes a bit a few months following the previous booster.

US data show protection against severe COVID illness is robust after the first booster, but falls somewhat from 91 percent effective in preventing severe illness to 78 percent effective over several months. Still, 78% protection is very good, but given how transmissible Omicron is, and the possible emergence of the Son-of-Omicron, which might be even more infectious and virulent, the idea behind a second booster is to offer people the chance to acquire the greatest level of protection possible. Not a bad idea.

The data that will be submitted to the FDA in support of the 2nd booster probably will include real-world data collected in Israel, which has already rolled out the second shot, and has reduced infections and serious illness in people older than 60. This will likely not be the last CoV-2 vax we will see. Pfizer and BioNTech are also working on a vaccine more effective against all variants and provide more lasting protection. That remains on the horizon, so stay tuned.

For those of us 65 and older, we (at least the males in that demographic) remember draft cards. As we entered our later years, the draft card, if unburned, was replaced in our wallets with our AARP cards, and then accompanied with our Medicare cards. Now we need a new wallet pocket to accommodate our vax card.

On a personal note about cards, your maturing and slowing bloggeur admits favoring a certain grocery store in town because they still card him when he buys his bottles of 80 proof anti-vax remedies.

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Update: Three days after this was first posted, Moderna announced that it also has asked for FDA approval for a second booster. However, they ask that the booster be approved for all adults over 18, and not just for those over 65 as Pfizer/BioNTech have done. This request, like the one submitted by Pfizer/BioNTech is largely based on recent data from Israel

Moderna made a strategic decision to request approval for all adults in order to give the FDA flexibility in deciding which patients would be good candidates for the booster. In other words, they could decide that it also would benefit under 65 and so recommend.

 

 


Son Of Omicron

“A rose is a rose is a rose.” –Gertrude Stein

Omicron is Omicron is Omicron (except when it becomes something different).

Two-plus years into the pandemic, many Americans are ready to declare the COVID crisis over. But, we have been at this juncture before—at the end of the very first surge (remember “flattening the curve?”), and again as Delta faded. Each time, a new virus variant came roaring back. Why should it be different now?

There are reports of two new sons of Omicron circulating in the world. The original Omicron, or BA.1 has spawned BA.2 and BA.3. While little is known about BA.3 at this time, very early indications are that BA.2 represents an even more infectious variant of Omicron, and it is spreading around the world and the US. This variant of a variant seems to be about 30% more infectious than Omicron BA.1. It quickly overtook BA.1 in South Africa and other countries and has caused a second Omicron surge in Denmark. BA.2 has been detected in 74 countries, and has become dominant in at least 10 of them: Bangladesh, Brunei, China, Denmark, Guam, India, Montenegro, Nepal, Pakistan and the Philippines, according to the World Health Organization's weekly epidemiological report.

In the US, BA.2 has been reported in 47 states and accounts for ~4% of all new infections according to the CDC, and it appears to be doubling fast. Samuel Scarpino, director of pathogen surveillance at the Rockefeller Foundation says that if infections double again to 8%, we will be in another exponential growth phase, or the fifth wave of the pandemic. In other words, BA.2 seems to be quickly backfilling the vacuum left as BA.1 peters out.

While BA.2 clearly arose from BA.1, it carries dozens of additional gene changes, making BA.2 as distinct from BA.1 as the Alpha, Beta, Gamma and Delta variants were from each other. This suggests that BA.2 might soon be given its own unique Greek letter designation.

What does BA.2 augur? While vaccination and prior infection still appear to protect fairly well against BA.2, this variant still seems more adept at skirting the immune system then the original Omicron. An early report also shows that vaccine induced antibodies often fail to neutralize BA.2 in tissue culture, and that the virus better replicates than BA.1 in nasal epithelial cell cultures. Nevertheless, those who have been vaccinated and boosted are 74% less likely to become ill from BA.2.

Hopefully, this reduced immunity will still be enough to provide an immunological redoubt against extensive spread of BA.2. The best thing that could happen is that as we become increasingly immunized by vaccine and infection, it might be enough to continue the drop in BA.1 Omicron infections, and check any surge from the new BA.2 variant. This is speculation at this point, and one thing we have learned over the last 2+ years is that the virus does not often respond as expected.

Then there is this: Very preliminary laboratory data hint that BA.2 might cause more severe disease than BA.1, and it appears capable of foiling some of the key weapons we have against COVID-19. In initial lab studies, a Japanese team reported that BA.2 has structural features that might make it as virulent as Delta was. This prediction of increased virulence was supported by hamster infection experiments, but this has yet to be confirmed or refuted in real-life epidemiological studies. Rest assured, those studies are underway, so we will see.

BA.2 also is almost completely resistant to some COVID treatments, such as sotrovimab, a monoclonal antibody therapy that is currently used against Omicron.

Bottom line: During the Spanish flu, as people wearied of the social restrictions designed to prevent the spread of the virus (there were no vaccines or drugs for flu then), many pushed back against the restrictions, which led to premature relaxation of the mandates. Cities like Denver and Philadelphia, which lifted their mandates early paid a hefty price. Other cities like St. Louis, which took a more cautious approach were relatively unscathed. Let’s hope that we are not relaxing and entering a “control phase” too quickly.

What’s ahead of us is not COVID’s end, but might be the start of a phase in which we continue to invest in measures to continue to shrink the virus’s burden. Success in this is not entirely up to us. The virus will have a say too. Our future will depend both on the virus’s continued and unpredictable evolution and on our responses, both immunological and social. The goal is to get ahead of any new variants with wide spread immunity and a growing formulary of antibody and drug treatments, and, yes, this might also require renewed mandates.

A detailed report  looking at past suspected coronavirus pandemics (e.g., the Russian “flu”of 1889, which was probably a coronavirus) published last August in the journal Microbial Biotechnology, suggested plausible scenarios in which elevated levels of COVID-19 deaths could last another five years or longer. This of course depends on what happens to and after BA.2.

It probably is not quite time to relax all mask mandates or let up on the push to vaccinate.

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Harry Became Severely Disabled After The Vaccine

Does the crowing of a rooster cause the sun to rise?

Harry: A follower of this blog, recently wrote to me about the experience of his senior friend, Harry. With permission, I relay the story here and add some thoughts.

Harry was 80 years old and living a healthy, robust life. He did his own home improvement projects, he was mobile and drove everywhere--he lived an active life. His only health concern was a bit of a problem with high blood pressure (who doesn’t at his age?) that was well controlled with a statin drug.

But, soon after his third shot (booster), his shoulder in the non-injection arm began stiffening. After that, one side of his groin became very painful and the pain migrated to the other side and then began shooting into his legs. Within weeks, he was unable to walk, relying on a walker or wheelchair. He became home-bound. His painful arm is now useless—he needs to hoist it with his other hand to get dressed. Same with both legs. Harry gets by each day on pain meds, but he is reluctant to take a higher dosage to fully control the pain as it makes him too groggy, so he only sleeps an hour or two at night due to the pain, then catnaps in his recliner throughout the day.

This sudden and quick decline began about a month after his booster shot so he was convinced his new maladies were a consequence of the vaccine.

VAERS: Harry’s case is the sort of case that is reported to the CDC’s Vaccine Adverse Effects Reporting Site or VAERS. When someone begins experiencing untoward health problems soon after vaccination they or their doc can easily report it on the VAERS site, which has served as an early warning system for identifying rare side effects of vaccines since 1990. Thousands of people have reported post-vaccination symptoms, and the site is accessible to anyone. Hence, there is a CDC database listing thousands of reports of health problems following COVID vaccination that you can pull up after a few clicks.

The CDC uses this uncorroborated raw anecdotal information to look for patterns that could point to previously unknown side effects of vaccines. This is common practice for all medicines after they have been approved for use. Data from clinical trials that form the basis for approval or rejection of a new medicine or vaccine only include results from ~40,000 test subjects. That is enough to discover very significant and fairly common side effects. But, after the medicine gets on the market, patient data still are collected in order to see if there are serious side effects that only appear in, say, one out of 250,000 people and that would not be found during the clinical trial on just 40,000 subjects. Remember the COX-2 anti-inflammatory drugs that were widely used in the 90s but were pulled because they were found to cause rare, but serious cardiovascular problems? This was found by collecting post-approval data from a few million people who had taken the drugs. Evaluating data collected after a medicine is on the market is referred to as post-market or Phase IV research. This is what the CDC uses the VAERS database for.

The CDC then digs into the raw VAERS reports to make sense of them. They first confirm the reports and then to see if they are just correlations or causative. Scientists look at further health data on the patients, and look for similar recurring problems in other patients. This also means that the raw data reported on the VAERS site are just that—raw. The raw data you can see on the site have not been confirmed or determined to have actually arisen from a vaccine side effect. In fact, the VAERS web site carries this clear disclaimer:

“VAERS reports alone cannot be used to determine if a vaccine caused or contributed to an adverse event or illness. The reports may contain information that is incomplete, inaccurate, coincidental, or unverifiable. In large part, reports to VAERS are voluntary, which means they are subject to biases. This creates specific limitations on how the data can be used scientifically. Data from VAERS reports should always be interpreted with these limitations in mind.”

The task for the CDC then is to separate health complaints that are just coincidental (i.e., that would have happened anyway without the vaccine) from those that are causal (i.e., that were caused by the vaccine). The fact alone that someone vomited a day after being vaccinated cannot be taken as proof that the vaccine caused the vomiting. There is a big difference between correlation, i.e., when two unrelated things happen together, vs causation when one thing leads to the other thing.

But, this is what the vaccine naysayers are doing—they look at the VAERS site and believe that all those raw reports are causative reports showing that the vaccines harm people. In other words, they completely ignore (or do not even read) the CDC disclaimer that the VAERS data are very incomplete and require further investigation before any conclusions can be drawn. When you hear someone on social media, TV, or the radio claim that tens of thousands of people have been seriously hurt by the vaccines, they are basing that claim on an incompetent (and possibly dishonest) use of the raw, uncorroborated VAERS data. I know this because every time I ask someone to back up their claim that the vaccines have injured tens of thousands of people, they eventually cite the VAERS database. When I quiz them further, most clearly have not even looked at the complicated VAERS web site, but are reporting second hand what they have heard elsewhere.

The truth is that few of the VAERS reports have been confirmed to be related to vaccination. Furthermore, the side effects mostly are of the “sore arm” variety, while serious health effects are vanishingly rare. Only about 200 people have actually died from the vaccines. All this compares to the almost 900,000 deaths (and counting) from COVID, and the ~20 million (and counting) cases of long term debilitation from long COVID. Remember, both the deaths and long COVID are prevented by the vaccines.

Back to Harry: Harry developed his debilitating conditions shortly after his third shot and attributed his woes to the vaccine. That is a temporal correlation—the debilitation happened shortly after the vaccine. But, is there anything that proves the vaccine caused Harry’s debilitation?  Well, a deep dive into Harry’s medical condition, like the CDC does into the data in its VAERS data, proves the vaccine did not cause Harry’s condition.

Sadly, a couple of days ago my blog friend told me that recent scans showed a mass on Harry’s lung. He has end-stage lung cancer that has spread to his pelvic bones and shoulder causing severe bone lesions and the pain. He will soon die from untreatable advanced cancer. It seems that Harry has a 50+ history as a smoker. But, he, as well as folks who abuse the VAERS system, totally ignore that kind of history and jump on the less-likely correlation between vaccination and diminishing health as proving a cause and effect relationship between the two. In doing this, people must assume that there could be no other causative factor for any malady that appears shortly after vaccination. Harry himself, ignored his long history of smoking, which is, by far, the leading cause of lung cancer, while the vaccines have been associated with zero cases of cancer.

This is a sad example of the mental gymnastics anti-vaxers resort to in order to confirm their bias against the vaccine. Real data be damned once they see a simple correlation that fits their bias.

Bottom line: Just as the vaccine did not cause Harry’s cancer, the crowing of the rooster does not cause the sun to rise. Both are correlations of events only temporally, not causally related.

Do not buy into the claims that the VAERS shows that people are suffering by the thousands from the vaccines. It is not true.


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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