Covid ‘Doesn’t Discriminate by Age’: Serious Cases on the Rise in Younger Adults

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Yves here. We find ourselves too often having to debunk Covid myths. The biggest is mortality is all you have to worry about. The second is that only old people are at risk. This post tackles the second urban legend.

By Will Stone. Originally published at Kaiser Health News

After spending much of the past year tending to elderly patients, doctors are seeing a clear demographic shift: young and middle-aged adults make up a growing share of the patients in covid-19 hospital wards.

It’s both a sign of the country’s success in protecting the elderly through vaccination and an urgent reminder that younger generations will pay a heavy price if the outbreak is allowed to simmer in communities across the country.

“We’re now seeing people in their 30s, 40s and 50s — young people who are really sick,” said Dr. Vishnu Chundi, a specialist in infectious diseases and chair of the Chicago Medical Society’s covid-19 task force. “Most of them make it, but some do not. … I just lost a 32-year-old with two children, so it’s heartbreaking.”

Nationally, adults under 50 now account for the most hospitalized covid patients in the country — about 36% of all hospital admissions. Those ages 50 to 64 account for the second-highest number of hospitalizations, or about 31%. Meanwhile, hospitalizations among adults 65 and older have fallen significantly.

About 32% of the U.S. population is now fully vaccinated, but the vast majority are people older than 65 — a group that was prioritized in the initial phase of the vaccine rollout.

Although new infections are gradually declining nationwide, some regions have contended with a resurgence of the coronavirus in recent months — what some have called a “fourth wave” — propelled by the B.1.1.7 variant, first identified in the United Kingdom, which is estimated to be somewhere between 40% and 70% more contagious.

As many states ditch pandemic precautions, this more virulent strain still has ample room to spread among the younger population, which remains broadly susceptible to the disease.

The emergence of more dangerous strains of the virus in the U.S. — including variants first discovered in South Africa and Brazil — has made the vaccination effort all the more urgent.

“We are in a whole different ballgame,” said Judith Malmgren, an epidemiologist at the University of Washington.

Rising infections among young adults create a “reservoir of disease” that eventually “spills over into the rest of society” — one that has yet to reach herd immunity — and portends a broader surge in cases, she said.

Fortunately, the chance of dying of covid remains very small for people under 50, but this age group can become seriously ill or experience long-term symptoms after the initial infection. People with underlying conditions such as obesity and heart disease are also more likely to become seriously ill.

“B.1.1.7 doesn’t discriminate by age, and when it comes to young people, our messaging on this is still too soft,” Malmgren said.

Hospitals Filled With Younger, Sicker People

Across the country, the influx of younger patients with covid has startled clinicians who describe hospital beds filled with patients, many of whom appear sicker than what was seen during previous waves of the pandemic.

“A lot of them are requiring ICU care,” said Dr. Michelle Barron, head of infection prevention and control at UCHealth, one of Colorado’s large hospital systems, as compared with earlier in the pandemic.

The median age of covid patients at UCHealth hospitals has dropped by more than 10 years in the past few weeks, from 59 down to about 48 years old, Barron said.

“I think we will continue to see that, especially if there’s not a lot of vaccine uptake in these groups,” she said.

While most hospitals are far from the onslaught of illness seen during the winter, the explosion of cases in Michigan underscores the potential fallout of loosening restrictions when a large share of adults are not yet vaccinated.

There’s strong evidence that all three vaccines being used in the U.S. provide good protection against the U.K. variant.

One study suggests that the B.1.1.7 variant doesn’t lead to more severe illness, as was previously thought. However, patients infected with the variant appear more likely to have more of the virus in their bodies than those with the previously dominant strain, which may help explain why it spreads more easily.

“We think that this may be causing more of these hospitalizations in younger people,” said Dr. Rachael Lee at the University of Alabama-Birmingham hospital.

Lee’s hospital also has observed an uptick in younger patients. As in other Southern states, Alabama has a low rate of vaccine uptake.

But even in Washington state, where much of the population is opting to get the vaccine, hospitalizations have been rising steadily since early March, especially among young people. In the Seattle area, more people in their 20s are now being hospitalized for covid than people in their 70s, according to Dr. Jeff Duchin, public health chief officer for Seattle and King County.

“We don’t yet have enough younger adults vaccinated to counteract the increased ease with which the variants spread,” said Duchin at a recent press briefing.

Nationwide, about 32% of people in their 40s are fully vaccinated, compared with 27% of people in their 30s. That share drops to about 18% for 18- to 29-year-olds.

“I’m hopeful that the death curve is not going to rise as fast, but it is putting a strain on the health system,” said Dr. Nathaniel Schlicher, an emergency physician and president of the Washington State Medical Association.

Schlicher, also in his late 30s, recalls with horror two of his recent patients — close to his age and previously healthy — who were admitted with new-onset heart failure caused by covid.

“I’ve seen that up close and that’s what scares the hell out of me,” he said.

“I understand young people feeling invincible, but what I would just tell them is — don’t be afraid of dying, be afraid of heart failure, lung damage and not being able to do the things that you love to do.”

Will Younger Adults Get Vaccinated?

Doctors and public health experts hope that the troubling spike in hospitalizations among the younger demographic will be temporary — one that vaccines will soon counteract. It was only on April 19 that all adults became eligible for a covid vaccine, although they were available in some states much sooner.

But some concerning national polls indicate a sizable portion of teens and adults in their 20s and 30s don’t necessarily have plans to get vaccinated.

“We just need to make it super easy — not inconvenient in any way,” said Malmgren, the Washington epidemiologist. “We have to put our minds to it and think a little differently.”

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47 comments

  1. Frenchguy

    Covid does discriminate by age though, as the article itself says: “Fortunately, the chance of dying of covid remains very small for people under 50”.

    As for the rise of cases among young people, I closely follow French data (easily available here: https://geodes.santepubliquefrance.fr/) and while it’s true that there is a noticeable rise in the share of young patients it’s right in line with their vaccination share which is, rightly, much lower than old people. It is perfectly normal that the population that is not immunized will tend to get sicker and there is no indications that the disease has become more lethal for them…

    Reply
    1. Reality Bites

      The problem is that we are at a stage where there younger crowd is being hit with far more problematic variants than we saw earlier, as the article also points out. The reopening of schools also means that cases are rising fast in the youngest demographics as well. The long term problems that can come with COVID (organ damage, long COVID, etc.) bode ill for people that still have most of their lives ahead of them.

      Reply
      1. Eric

        There is no evidence that reopening schools will lead to cases increasing or that there is correlation between the two. If there is community spread, of course children will be impacted, but that is not directly tied to schools themselves.

        Reply
        1. Mantid

          Dear Eric, unfortunately there IS evidence “that reopening schools will lead to cases increasing”. Please read a recent article posted in our very own NC from 3-21-2021. Link: https://www.nakedcapitalism.com/2021/03/new-cdc-guidelines-to-reopen-schools-based-on-outdated-cherry-picked-and-misinterpreted-data-puts-students-teachers-and-communities-at-risk.html

          The article was a review of more recent studies showing that earlier assumptions of Covid and students in/out of school were incorrect. Scroll down to section #4 in that article. To quote the article: “4. Increases in the prevalence of infection among school-age groups preceded rises of infection in other age groups.” Continuing on ….. “new studies suggest that infections among children at school do not just reflect infection rates in the community. Rather, they drive increases in infection within the community through spreading from schools into homes, and from there to the broader community.” The complete article is interesting to read because it has links to all specific studies addressed and through those links one can get a more clear and updated picture of why opening schools too early is dangerous for all: the students, the teachers, the family members and eventually the community at large – in that order. I am a public school teacher and have kept my eye on this specific debate for obvious reasons. To keep Covid down, keep kids out of school, at least the way schools in the U.S. are run.

          In Sweden and other cultures there is a different approach to the daily life of a student. In Sweden, nearly every one hour long class includes a 10 – 15 minute break outdoors, even in the dead of winter. Students get fresh air and the briefly empty classroom’s air is refreshed. We have learned that Covid is spread primarily through aerosols, not contact with surfaces. In the U.S. children can easily spend two hours in the same room, with windows closed, often sitting in a desk. That is a situation ripe for the spread of Covid.

          Reply
      2. Frenchguy

        And what I’m saying is that while there are lots of anecdotal stories about “more young patients in hospital”, those stories have been around basically since the start of the epidemics and that there is no evidence in the hospital age data that this is the case.

        Reply
    2. TimH

      Younger people assess risks more lightly than older, so are generally more likely to expose themselves to Covid infection risk situations.

      Reply
  2. The Rev Kev

    It’s one thing to realize that long covid is actually a thing. And when you are talking about old people suffering from it, policy makers are inclined to shrug their shoulders about this development. But now that more and more younger people are experiencing this, surely those very same policy makers are beginning to become aware of the long term strain that this will impose on each country’s medical system. No happy answers here.

    Reply
    1. Jesper

      I suspect that the powers that be will only realize that long covid is real once it affects someone close to them.

      Reply
      1. PHLDenizen

        Given the medical establishment’s visceral hatred of long-haul Lyme, I’m not particularly encouraged that this will ever materialize as concrete benefits for those who suffer from it.

        The anti-vaxxer crowd nuked LYMErix back in the late 90s, so decades of unnecessary infections resulted. Oddly enough, Pfizer decided to get into the Lyme vaccine game recently. Then there’s the whole “contested illness” status of post-treatment Lyme infections aka the “Lyme Wars”. Infectious disease specialists insisted that a single round of antibiotics was sufficient to treat, asserted that patients suffering from lingering symptoms were essentially crazy, and moved to strip the licenses of MDs who adopted a non-heterodox view. Establishment intellectual violence against heretics.

        Insurance companies will likely decide “if it doesn’t show up on a test, it doesn’t exist”, which is the exact problem with Lyme. Even clearing that hurdle, I don’t imagine those without cash on hand to pay for treatment will find any safe harbor.

        Reply
        1. Jack Parsons

          A Lyme vax is available for dogs in America. If you find a friendly veterinarian, they will hook you up.

          Yes, really.

          Reply
    2. megrim

      I think that pharmaceutical companies are rubbing their hands together in anticipation of a whole new market of chronically ill people to price gouge.

      Reply
      1. drumlin woodchuckles

        And directing their agents and frontmen at WHO and CDC to obstruct counter-aerosol action as long as possible to make sure that whole new market comes through.

        Reply
  3. William Hunter Duncan

    I’m torn about getting the Covid vaccine. I know it is mostly taken for granted that it is safe, but the first vaccinations in earnest began less than six months ago and that does not seem to me ample time by any means, to guage long term ill effects if any, for what remains essentially an experimental vaccine.

    There was concern for years that mRNA vaccines could cause auto-immune diseases. That concern evaporated in the face of an economy devastating pandemic. How long will it take before we can know for certain if such problems arise or not? I don’t know.

    My caution at this point seems equal, avoiding Covid and any potential problem from rhe vaccine.

    Reply
    1. PKMKII

      There’s a common misconception that medicine is, I have this illness or injury, I go to doctor, doctor says “this is the things that will fix what ails you.” In reality, it’s more like, of all the things we can do for you, this is the one that the evidence points to as being the least bad. And it’s not always something that can be reduced to a metric in terms of the risk of the side effects among the least bad choices. So it’s a question of, which set of potential side effects are least bad, from your perspective.

      Reply
      1. Fern

        Why? I’m genuinely curious about why people believe that the Johnson & Johnson vaccine is a better choice.

        Reply
        1. reprobate

          Some people are leery of mRNA vaccines, either in general or at least until there is more long-term data on them. The J&J vaccine uses more established technology.

          Reply
      2. kareninca

        Huh? That is not a helpful comment. In fact, it makes me less inclined to have that particular vaccine than I already was.

        Reply
        1. Yves Smith Post author

          Nick was addressing an individual with a particular vaccine concern. I have heard reports from MDs and friends with MDs in their families of worsening of autoimmune symptoms with the Pfizer and Moderna vaccines, to the degree that all of the autoimmune disease patients in one MD’s practice refused the second shot. With 2 of the 3 patients, the symptoms abated in a few weeks but they weren’t willing to take a chance. With the third, they haven’t yet.

          If you don’t have an autoimmune disease this is not a risk you need to worry about.

          Reply
          1. kareninca

            Thank you for the clarification, and also for the info about the Pfizer and Moderna vaccines. I do know a lot of people with autoimmune disease.

            Reply
    2. PlutoniumKun

      Its a real dilemma. On a straightforward balance of evidence basis, I don’t think there is any real doubt but that taking a vaccine is the best option for everyone, including low risk groups. The ‘reasonable’ worst case scenario for vaccines is significantly less worrying than the likely damage for any individual of getting Covid.

      But as for the issue of which vaccine, its almost impossible I think to make any reasoned conclusion on the available evidence. They simply haven’t been out there long enough. I was very sceptical about the RNA vaccines, but they are (so far) working extremely well, significantly better than the non-RNA alternatives it would seem. If I was in a high risk category, I would personally prefer the Pfizer vaccine as it seems the most effective. For those in lower risk categories the J&J seems a better option, but with the blood clot issue the balance of evidence may be different for younger women.

      Reply
    3. eg

      I took Astra Zeneca (it was what was available earliest for my age group in Canada) along with well over 100 million others worldwide. It’s not an mRNA vaccine.

      Reply
    4. Ian

      Vaccines take a long time to develop, in part, because of bureaucracy. When there is a global pandemic, some of those steps are understandably lessened or eliminated thereby speeding up the process. Get the vaccine.

      Reply
  4. Ignacio

    Early in the pandemic it was already seen that young people, even child, could suffer severe Covid, included death which was/is possibly associated with the multiplicity of infection or virus entry load. According to this article it seems the risk is quite higher with the new strains probably because these are released in higher amounts resulting in high multiplicity of infection being more probable. A risk that one has to be aware about it no matter if one has been vaccinated or not. Measures to reduce such risk will have to be kept for long to avoid any of the ugly outcomes described above. No reasons to relax about Covid and with time it will have to be analysed the prevalence of this and new strains that will surge.

    We have no previous experience of a pandemic like this (our ancestors have had but without info we can evaluate) and never an attempt of general vaccination has been made against a respiratory virus that is new so nobody has a clue on how will this evolve. It may take years until one can be confident the risks are low enough to forget about cautionary measures. My guess is that the more vaccinated individuals, the less advantage have these strains but who knows, and exactly who knows what is the percentage of vaccinated needed to see this effect though probably very high.

    Reply
    1. PlutoniumKun

      I wonder how much study has taken place of the Pandemic of 1889-1890. It seems to have been largely confirmed to have been a coronavirus. The initial wave was over in less than a year, but there were subsequent waves for about 5 years before it finally burnt itself out.

      I think the worst case scenario is that incomplete and inconsistent vaccinations results in further variants, possibly prolonging the outbreak, at least in poorer countries (with perhaps rebounds hitting the west and China). What I think is most striking about this pandemic – and maybe unique so far as I know – is that it ran so rapidly through some countries leaving others largely untouched, only to hit those countries very hard a year after the initial wave. Its not just India – much of SE Asia is now in big trouble, and it could get very bad if it gets loose again in the Philippines or Indonesia. As for Africa, I think thats anyones guess. Its almost as if the virus is sentient and taunting those countries who had the temerity to declare victory. It is behaving a bit like one of those bad guys in fake wrestling matches.

      Reply
  5. Carla

    Lambert posted this on another thread:

    https://www.youtube.com/watch?v=YQdKsLZjmaQ

    It is Dr. John Campbell giving a summary of his long interview with an Indian infectious disease expert, Dr. Nair. (The original interview is available, but had problematic audio.) At just past the 11 minute mark of this link, Campbell summarizes what Nair had to say about the use of ivermectin along with doxycycline to treat mild to moderate Covid-19. Nair was unequivocal that this combination prevented the progression of the disease to a more severe form.

    I’m repeating this here just to get it in front of as many eyes as possible. Big Pharma does NOT want us to know.

    Reply
  6. cm

    After spending much of the past year tending to elderly patients, doctors are seeing a clear demographic shift: young and middle-aged adults make up a growing share of the patients in covid-19 hospital wards.

    Am I misreading this graph???

    18-49 doesn’t appear to have moved since the onset, remaining under 10% the entire time. What am I missing?

    Reply
    1. Mantid

      CM, the graph you link to is from the CDC, a fairly suspect if not outright lost entity. I wouldn’t trust their graph even if I could read it.

      Reply
      1. ChickenLittle

        suspect if not outright lost entity
        you ok there bud? tell me more, oh wise authority! Lol

        Reply
    2. Paua Fritter

      What you are missing is that the passage which you quoted is talking about an increase in the proportion of the people in hospital who belong to the younger age group, not in the proportion of people from that age group who (when infected) end up in hospital. Since the (more vaccinated) older age groups are now much less likely to be hospitalized, the proportion of the hospitalized people who come from the younger (less vaccinated) group has risen.

      Reply
      1. Yves Smith Post author

        Sorry, the spin of the article (“young people get vaccinated!”) obscures a key point that undercuts the shift is vaccine driven:

        Across the country, the influx of younger patients with covid has startled clinicians who describe hospital beds filled with patients, many of whom appear sicker than what was seen during previous waves of the pandemic.

        “A lot of them are requiring ICU care,” said Dr. Michelle Barron, head of infection prevention and control at UCHealth, one of Colorado’s large hospital systems, as compared with earlier in the pandemic.

        And as early as January, the US press was reporting that the new variants were more hazardous to young people:

        U.K. Coronavirus Variant Probed for Increased Risk to Younger People Wall Street Journal

        The CDC says this COVID variant is now the most dominant. And it hits younger people. Fortune

        I am now kicking myself for not having written an intro to put this piece in context.

        Reply
        1. Paua Fritter

          Oh I agree there very likely is an increase in the hospitalization rate for young people arising from greater virulence of some novel strains, which might even have increased virulence specifically in younger people (irrespective of vaccination status), but in order for the proportion of young people in the hospital wards to increase significantly it’s enough that there’s a drastic fall in hospitalization rates for older vaccinated folks, and I would think that’s the larger factor.

          Reply
  7. Laura in So Cal

    Disappointing article in that there are very few actual numbers in it. What it seems to indicate is that the proportion of hospital patients that are under 65 has increased…which is exactly what you would expect if the vaccines are working to reduce hospitalization among those who are vaccinated since the elderly were prioritized.
    “Nationally, adults under 50 now account for the most hospitalized covid patients in the country — about 36% of all hospital admissions. Those ages 50 to 64 account for the second-highest number of hospitalizations, or about 31%. Meanwhile, hospitalizations among adults 65 and older have fallen significantly.”

    That doesn’t mean that absolute numbers have changed at all…I just can’t tell with the lack of actual statistics in the article.

    Reply
    1. wadge22

      Agreed. With none of what little data is there offering any support for the headline claim that “serious cases on the rise in younger adults.”
      Clicking through, I noticed it’s a KHN/NPR joint production. Now the subtle dig on the south, the implied obviousness of superior uptake in a west coast blue state, the scolding of large population groups, and the heart string tugging by way of anecdote from PMCs all seem a little more in place.

      Reply
      1. Yves Smith Post author

        That’s ad hominem and a violation of our Site Policies.

        And I can tell you via my tiny network of Alabama contacts, there are four people under 50 who have died of Covid, three of that four under 40, and one 29 year old with zero comorbidities who has been hospitalized for weeks.

        Reply
    2. Yves Smith Post author

      Please tell me where to get the data. There’s no national, state, or even city-wide information storehouses. Oh, theoretically the CDC has data but reporting is voluntary. So the only kinda-sorta OK data is on deaths (and I assume you have seen the many articles on undercounts) and positive test results.

      In my prior life, I’ve regularly done studies where hard data did not exist or was unreliable. I can tell you it’s a huge mistake to reject front-line reports as you are doing now. Hospital staff will react not to a relative increase but an absolute increase in younger patients. You were seeing just about no young patients in hospitals before, or did you forget that?

      And you ignore that young people are more vulnerable to some of the variants than they were to the first Covid variants. So this result is not at all a surprise.

      Reply
      1. Laura in So Cal

        I was curious so I went looking for current hospitalization for COVID by age. You are correct that It was hard to find. I finally did find some data that is pretty recent by digging into some links in a footnote on a CDC page.

        https://gis.cdc.gov/grasp/COVIDNet/COVID19_5.html

        I downloaded the data & it does look like there is a bump in the 18-49 and 50-64 age groups back to the level that existed in Dec 2020 & Jan 2021 but no bump in the over 65 group which is why the proportions have changed as noted in the article. Reading the footnotes, COVIDNet is a surveillance program so it is only looking at a subset group of counties and states so it could miss a local geographic surge.

        Counts of COVID-19-associated Hospitalizations by Age from the COVID-NET Network (data downloaded on 5/4/2021)
        Centers for Disease Control and Prevention
        WEEK_NUMBER 0-4 YR 5-17 YR 18-49 YR 50-64 YR 65+ YR
        2020-10 0 0 10 7 17
        2020-11 0 0 51 79 84
        2020-12 0 4 254 286 418
        2020-13 6 5 638 792 1061
        2020-14 11 11 656 1024 1398
        2020-15 9 7 635 912 1445
        2020-16 11 8 733 956 1552
        2020-17 10 14 770 823 1506
        2020-18 11 20 772 853 1391
        2020-19 9 21 739 774 1134
        2020-20 13 15 709 712 1045
        2020-21 17 21 733 668 959
        2020-22 14 25 634 526 791
        2020-23 16 18 523 427 590
        2020-24 14 14 464 346 466
        2020-25 15 10 473 366 432
        2020-26 13 22 572 417 446
        2020-27 10 20 730 522 655
        2020-28 21 29 886 707 862
        2020-29 15 30 913 750 915
        2020-30 23 22 786 726 913
        2020-31 16 20 730 643 834
        2020-32 12 21 690 562 768
        2020-33 12 23 604 526 671
        2020-34 12 24 513 485 651
        2020-35 10 29 488 352 539
        2020-36 19 20 399 346 510
        2020-37 7 17 388 343 480
        2020-38 9 22 374 316 505
        2020-39 15 12 401 374 557
        2020-40 9 19 423 377 583
        2020-41 8 21 466 479 779
        2020-42 10 25 567 508 873
        2020-43 11 25 578 693 1037
        2020-44 13 29 707 807 1360
        2020-45 24 51 946 1033 1764
        2020-46 22 57 1137 1323 2447
        2020-47 28 35 1201 1465 2935
        2020-48 25 47 1256 1525 3087
        2020-49 41 51 1325 1555 3197
        2020-50 42 41 1396 1607 3260
        2020-51 33 43 1271 1578 3222
        2020-52 36 57 1201 1591 3269
        2020-53 28 48 1291 1595 3345
        2021-1 37 67 1381 1746 3431
        2021-2 36 55 1254 1558 2964
        2021-3 29 51 1111 1367 2579
        2021-4 24 56 944 1113 2125
        2021-5 22 46 805 953 1852
        2021-6 20 41 721 748 1280
        2021-7 17 43 624 677 1131
        2021-8 10 34 601 644 974
        2021-9 12 26 559 595 771
        2021-10 21 19 577 619 789
        2021-11 21 34 659 744 774
        2021-12 19 37 753 871 910
        2021-13 26 39 929 886 861
        2021-14 27 40 1127 1041 930
        2021-15 17 48 1033 1046 898
        2021-16 25 41 740 652 625
        2021-17 0 0 0 0 0

        The Coronavirus Disease 2019 (COVID-19)-Associated Hospitalization Surveillance Network (COVID-NET) hospitalization data are preliminary and subject to change as more data become available. In particular, case counts for recent hospital admissions are subject to lag. As data are received each week, prior case counts are updated accordingly.
        COVID-NET conducts population-based surveillance for laboratory-confirmed COVID-19-associated hospitalizations in children (less than 18 years of age) and adults. COVID-NET covers nearly 100 counties in the 10 Emerging Infections Program (EIP) states (CA, CO, CT, GA, MD, MN, NM, NY, OR, TN) and four Influenza Hospitalization Surveillance Project (IHSP) states (IA, MI, OH, and UT).

        Reply
      2. GM

        This paper is from 2007:

        https://pubmed.ncbi.nlm.nih.gov/17222058/

        It concerns the original SARS virus.

        The goal was to create a mouse model system in which they can easily study the disease and to do this the fast and easy way (the hard way, and it was still quite hard and laborious back then, is to make a humanized mouse expressing the human ACE2; though that was create eventually too).

        It took 15 passages to take the original virus, which was harmless to mice, and turn it into a virus that is lethal to mice. And during those 15 passages it accumulated just six mutations.

        Young inbred mice support SARS-coronavirus (SARS-CoV) replication in the respiratory tract and are available in sufficient numbers for statistical evaluation. They are relatively inexpensive and easily accessible, but their use in SARS research is limited because they do not develop illness following infection. Older (12- to 14-mo-old) BALB/c mice develop clinical illness and pneumonitis, but they can be hard to procure, and immune senescence complicates pathogenesis studies. We adapted the SARS-CoV (Urbani strain) by serial passage in the respiratory tract of young BALB/c mice. Fifteen passages resulted in a virus (MA15) that is lethal for mice following intranasal inoculation. Lethality is preceded by rapid and high titer viral replication in lungs, viremia, and dissemination of virus to extrapulmonary sites accompanied by lymphopenia, neutrophilia, and pathological changes in the lungs. Abundant viral antigen is extensively distributed in bronchial epithelial cells and alveolar pneumocytes, and necrotic cellular debris is present in airways and alveoli, with only mild and focal pneumonitis. These observations suggest that mice infected with MA15 die from an overwhelming viral infection with extensive, virally mediated destruction of pneumocytes and ciliated epithelial cells. The MA15 virus has six coding mutations associated with adaptation and increased virulence; when introduced into a recombinant SARS-CoV, these mutations result in a highly virulent and lethal virus (rMA15), duplicating the phenotype of the biologically derived MA15 virus.

        Now guess what we have been doing over the past 15 months will all the “it is harmless to kids and young people, let them get infected to build up immunity”? We have been repeating that exact experiment. And it is not at all true that people will build immunity, exactly the opposite, natural immunity is short-lived and each reinfection will be on average because of all the havoc the previous one(s) have wreaked.

        P.S. That experiment has been repeated with humanized mice for SARS-CoV-2 too, over 30 passages. And guess what came out of it? The three key mutations in the Brazilian and South African variants plus a couple others that are known from in vitro studies to increase binding to the receptor by another one to two orders of magnitude (which will presumably make it yet more contagious and virulent to everyone, lowering the age distribution of the risk by a lot). We can expect those mutations to show up in the near future in the real-life SARS-CoV-2 too. Oh, and they lead to much more serious immune escape too.

        Reply
  8. Adrian D.

    As some have noted, it’s clear the author is keen to make their point especially when they include lines like this:

    “Nationally, adults under 50 now account for the most hospitalized Covid patients in the country — about 36% of all hospital admissions.” Which, if adults over 50 make up less than 36% suggests a huge number of kids are being hospitalised.

    It’s worrying, but I’d like to see some absolute figures rather than these percentages and anecdotes of what some doctors are seeing.

    Reply
    1. PlutoniumKun

      Thats really interesting, although from what I hear Tokyo might have quite different patterns from the other hotspots in Osaka and (previously) Hokkaido. I wonder what the explanation for that might be – infection via small children perhaps?

      Reply
      1. Acacia

        Good question, PK. All I could find is an interview with the director of the National Institute of Infectious Diseases (below), who suspects that it’s primarily due to two factors: (1) the mutant strain N501Y circulating in the Kansai region (Osaka), which he suggests is 1.32x as infectious, at least based upon current data, and (2) the unhindered circulation of people until the end of March (new SoE is in effect now).

        https://www.buzzfeed.com/jp/yutochiba/covid-19-n501y

        The article includes a nice graph showing the prevalence of the different strains of COVID-19 across Japan.

        Reply
  9. R

    You would think that an article touching upon the efficacy of the current vaccines against the new UK variant and others might enquire into whether said vaccines are working in the UK, since we achieved both near-100% coverage with home-grown Covid and about 50% coverage of the total population on first doses….

    It seems to be going OK here so it should be OK across the water, provided you don’t get too many refuseniks.

    Longer-term, I am unsettled by HMG’s sudden enthusiasm for giving all UK adults a third shot in the winter. I don’t follow the logic, since it is purported to be one of the existing vaccines and so not specific to a new mutant. Are there hard data showing fading immunity after six months or just a precaution that absence of evidence is not evidence of absence?

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