Coronavirus

Contrary to What the CDC's New COVID-19 Advice Implies, There Is Strong Evidence That Vaccination Curtails Virus Transmission

Research in Israel, the U.K., and the U.S. has found dramatic reductions in asymptomatic infections.

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The Centers for Disease Control and Prevention (CDC) today issued new guidance for people who have been vaccinated against COVID-19. The agency says fully vaccinated people should feel free to forgo face masks and physical distancing while mingling indoors with each other or with people from "a single household" who are at low risk from COVID-19. But it says vaccinated people should continue wearing masks and practicing physical distancing in public places or when visiting unvaccinated people in high-risk groups.

The CDC notes "the rapidly evolving science on COVID-19 vaccines." While there is ample evidence from clinical trials that vaccination dramatically reduces the odds of serious disease, hospitalization, and death, there are still some questions about the extent to which it prevents infection and transmission. Yet several studies provide strong evidence that vaccination protects not only people who receive shots but also unvaccinated people in their vicinity.

Even without that research, there are sound reasons to expect COVID-19 vaccination to reduce the spread of the disease. "First, when the vaccines were studied in macaque monkeys (during preclinical testing), they did eliminate asymptomatic infection," a March 2 article published by the Association of American Medical Colleges notes. "Researchers swabbed the vaccinated macaques' noses and found little or no virus. Second, the types of antibodies that are stimulated by most systemic vaccines (IgG and IgA) do tend to block viral infection in the nose (and no viral load in the nose most likely translates to no transmission). Finally, when monoclonal antibodies are given to COVID-19 patients, those antibodies reduce the viral load throughout the respiratory tract, including the nose."

Several studies add to that evidence. Researchers in Israel tracked nearly 600,000 people who received the two-dose Pfizer vaccine, comparing them to an equal number of unvaccinated controls matched for age, sex, "sector" (i.e., "general Jewish, Arab, or ultra-Orthodox Jewish"), neighborhood of residence, influenza vaccination history, pregnancy, and preexisting medical conditions associated with a higher COVID-19 risk. In a study published last month by The New England Journal of Medicine, they reported sharp reductions in asymptomatic infection as well as other outcomes.

During a follow-up period beginning seven days after the second dose, vaccinated subjects were 92 percent less likely to test positive for the coronavirus, 94 percent less likely to develop COVID-19 symptoms, and 92 percent less likely to suffer serious disease. In other words, the risk of infection at this stage was much smaller than it was in the unvaccinated group. Although that risk was not completely eliminated, the CDC notes that "preliminary data from Israel suggest that persons vaccinated with Pfizer-BioNTech COVID-19 vaccine who develop COVID-19 have a four-fold lower viral load than unvaccinated persons," which implies that they are less likely to transmit the virus even when they are infected.

What about newer virus variants? "This study estimates an average effectiveness of the vaccine over multiple strains," the authors of the NEJM study say. "Although we cannot provide a specific effectiveness estimate for the B.1.1.7 variant, the plateau observed during the later periods in the cumulative incidence curve for vaccinated persons suggests that the BNT162b2 vaccine is also effective for this variant, an observation consistent with previous reports that showed preserved neutralizing antibody titers. The B.1.351 variant was estimated to be rare in Israel at the time of data extraction."

Lancet study of more than 23,000 hospital workers in Scotland and Northern Ireland who were periodically tested for the coronavirus likewise found that the Pfizer vaccine dramatically reduced asymptomatic infection. Three weeks after the first dose, infection was reduced by 70 percent. Seven days after the second dose, the reduction rose to 85 percent. "Our study demonstrates that the BNT162b2 vaccine effectively prevents both symptomatic and asymptomatic infection in working age adults," the researchers report. Since "this cohort was vaccinated when the dominant variant in circulation was B1.1.7," the study "demonstrates effectiveness against this variant."

A preprint study of about 62,000 Mayo Clinic patients in four states found that "administration of two COVID-19 vaccine doses was 88.7% effective in preventing SARS-CoV-2 infection." Complementing the data from randomized clinical trials of the Pfizer and Moderna vaccines, the researchers said, "this study demonstrates their real-world effectiveness in reducing the rates of SARS-CoV-2 infection and COVID-19 severity among individuals at highest risk for infection."

As The New York Times notes, these findings are consistent with the results of animal research and studies involving smaller samples of people who participated in the Moderna and Johnson & Johnson clinical trials. In a study of eight vaccinated monkeys exposed to the virus, for example, seven were uninfected. Among a few dozen people who received the Moderna vaccine, infection was reduced by about two-thirds after the first dose. Johnson & Johnson's single-dose vaccine reduced infection by 74 percent in a subsample of 3,000 people.

"We feel confident that there's a reduction," University of Florida biostatistician Natalie Dean told the Times. "We don't know the exact magnitude, but it's not 100 percent." While the estimates "could change with more data," said Dan Barouch, a virologist at Beth Israel Medical Center in Boston, "the effect seems quite strong."

The evidence so far indicates that people who have been vaccinated are much less likely to be infected—perhaps as much as 92 percent less likely, judging from the Israeli study. That means they are much less likely to infect other people.

Encounters among vaccinated people, the focus of the CDC's guidance, obviously pose the lowest risk. The CDC's advice also allows close encounters between vaccinated people and unvaccinated people in low-risk groups, which suggests it's OK to hug your vaccinated parents or grandparents.

But the CDC wants vaccinated people to carry on as before in public places. Here we are talking about a potential risk to strangers, so the moral calculus is different. And given the CDC's habitual risk aversion, its recommendation regarding masks and physical distancing in public is not at all surprising. After all, even an 85 percent or 92 percent reduction in the likelihood that you are carrying the virus still means the chance is greater than zero.

"They should wear masks until we actually prove that vaccines prevent transmission," says Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases. Research that tracks close contacts of vaccinated people might prove that effect to Fauci's satisfaction. In the meantime, the Times says, "when vaccinated people can ditch the masks in public spaces will depend on how quickly the rates of disease drop and what percentage of people remain unvaccinated in the surrounding community."

Many vaccinated people are apt to see things differently, especially if they think the onus should be on members of high-risk groups to avoid situations that are conducive to virus transmission. Now that vaccines are widely available to older Americans and people with preexisting medical conditions, that argument has additional force.

The minimal inconvenience of wearing a mask during a trip to the grocery store (assuming the store no longer requires it) is a pretty easy way of reassuring people who are especially vulnerable to COVID-19 but have not managed to get their shots yet, especially since they ordinarily have no way of knowing who has been vaccinated. But as time goes by and daily new cases continue to drop, vaccinated Americans are apt to lose patience with people in high-risk groups who have the opportunity to get vaccinated but fail to do so.

NEXT: New CDC Guidance Says Vaccinated People Can Do a Tiny Bit of Socializing

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  1. Keep jumping motherfuckers! And don’t forget to ask “How high?”

    1. Nothing these idiots have told us about COVID has proven true. Latest CDC study found virtually no benefit whatsoever to masking – and it was a crappy study (obviously designed to boost benefits of mandates), so imagine what a good study might have shown!

      When they said it would all be worth it if it saved one life, I didn’t realize they were being literal!

      1. That CDC study was presented in a “unique” way. Large P values showing a minuscule change that is likely way inside measurement error. So, while that study is being used to show masks were somewhat effective, it actually shows the opposite.

        1. They effectively showed a statistically significant tiny change that likely couldn’t even be measured.

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          2. The term “asymptomatic infections” is the biggest crock of shit ever contrived. Invented to convince people that aren’t sick that the fraud PCR test says they are. You have to be beyond stupid to believe any of this.
            Sullem. You’re an imbecile.

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  2. DUH?!?

    In what bizarro universe would anyone believe that a vaccine designed and tested to inhibit virus reproduction would not slow its transmission?

    I mean, what the actual fuck does the CDC think we’re capable of believing?

    1. They’re going to keep saying stupid things until they get reach a conclusion.

      Science!

      1. The charts of excess deaths from all causes are reliable. They show that deaths began falling dramatically between 15/15/20 and 1/05/21. that is, before vaccine rollout. The only thing that proves is that I was right all along. Protect the vulnerable. Healthy people should live normally.

        1. 15/15/20?

          1. In the year 2525, if man is still alive?

            1. At this rate, by the year 1,000,000.5 we’ll be enslaved by giraffes…

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    2. what the actual fuck does the CDC think we’re capable of believing?

      They’re doing a clinical study as we speak.

    3. Pretty generally, anyone with any knowledge of modern biology would assume that if you’re vaccinated, then you not only won’t get it, but you certainly won’t have it at high enough levels to present a threat to others.

      “Follow the science” is great, but realize that for most things in science, 95% is considered about perfect. By that measure, these vaccines are nearly perfect.

      1. Stop the goddamn PCR tests.

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    4. It’s so fucking bizarre. With this virus everyone seems to be pretending to be completely ignorant about how viruses and immune systems work.

      1. Keeping 40 years of virology secret. Antibodies fading is one concrete example. The community knows antibodies fade for this class of virus but T cells confer long term immunity. Yet they practically screech “Anti bodies fade”. Its a way to say something that is true while basically lying through their teeth. Duplicitous bastards.

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  3. >>The minimal inconvenience of wearing a mask during a trip to the grocery store

    one man’s minimal inconvenience is another’s shackle.

    1. >>The minimal inconvenience of wearing a mask gold star during a trip to the grocery store

      1. Or a tattoo.

    2. I miss the days where wearing a mask in a grocery store would result in the police showing up.

      1. yeah, I made that comment at the liquor store where I’m well known…. they didn’t laugh. some people have no sense of humor.

        1. Next time do it while with your hand in your jacket pocket. Now THAT will be funny.

        2. That joke’s going to hit hard at a liquor store. Convenience store too. I know a store owner who has shot and killed an attempted robber before. He would not laugh at that either.

  4. Surely this means we now need to wear three masks.

    1. I see your three masks and raise you two masks.

      1. If you raise those two masks, you’re not wearing them properly, and Karen will be on your case in a Manhattan minute.

      2. I’ll see your combined FIVE masks, and raise you an anal swab! Used!

  5. Everything is contrary to what the CDC says. They are political hacks and worthless.

    1. How many more lies do they have to tell before the media stops reporting on the CDC like it did with Trump?

  6. As does prior infection, and what are we up to now? 150,000,000 prior infections?

    1. There are variants at play. Variants. Like fire ants, their various genes and nefarious intent laugh in the face of your supposed natural immunity.

      1. My boss got the ‘Vid bad a few months ago, and then when and got the vaccine anyways. Because… well I don’t know but he got sick again from the vaccine.

        1. Good. What a douche.

    2. yes… according to the CDC’s own numbers, and despite what the media would lead you to believe, there are only around 100 confirmed cases of reinfection in the whole world. Now even if that were a huge undercount, say it was 1000 times more, that is still 100,000, and would mean there was a 99.99% chance that infection gave a person immunity, yet still they won’t admit that.

      1. In mathematics, that’s known as “statistically zero.”

  7. If someone complains that you’re not wearing a mask in the grocery store, tell them that In the metaphysical sense, we’re all wearing masks.

    1. nobody remembers the pigface Twilight Zone … or the Zone where the inheiritants had to wear masks made by Gramps or they wouldn’t get da money

      1. Yes, I remember both those episodes. Even wrote about the pigface one:
        https://libertyunbound.com/individuals-matter/

        1. nice.

  8. “A reduction in the rate of asymptomatic spread”, what was the actual rate of asymptomatic spread before the vaccines came out?

    1. Zero.

      1. Zero point zero

        1. Fat, drunk, and stupid is no way to go through life, son…

  9. vaccinated Americans are apt to lose patience with people in high-risk groups

    Perhaps the CDC will permit the high-riskers to wear some kind of “badge”.

  10. “They should wear masks until we actually prove that vaccines prevent transmission,” says Anthony Fauci

    So what if they can’t prove that? Or prove just the opposite? Does this mean (as I suspect) that we are expected to wear masks and socially distance for the rest of our lives?

    1. OTOH, maybe he’ll come out with “They should stop wearing masks until we actually prove that masks prevent transmission.”

    2. Well, you know the flu vaccine isn’t 100% effective and then there are a bunch of cold viruses that have no vaccine at all, so yeeeeah.

  11. Screw Fauci. This tool won’t even admit that prior infection confers future immunity.

  12. in no universe will the risk ever be zero, so is it possible the CDC will recommend masks and distancing in public forever? probably

    1. Guaranteed.

      1. Mission creep and droolin’ Joe has no interest in limiting it.
        But no mean tweets?

    2. I predict they will be very vocal about people with symptoms of cold/flu/covid/whatever wearing masks in public for a long time to come. They may even try to recommend masks for everyone in public forever, but I think they’ll be forced to back off that pretty quickly.

  13. “They should wear masks until we actually prove that vaccines prevent transmission,” says Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases.

    Does this smug little gremlin actually understand what he saying? If a vaccine doesn’t prevent transmission of an illness, then it’s effectively worthless. Secondly, isn’t this a tacit admission that the vaccines weren’t tested thoroughly enough before getting them on the market?

    1. “Does this smug little gremlin actually understand what he saying?”

      I’m truly believe he does not. It appears that he got a PhD in immunology by knowing exactly the right levers to pull, then got himself a position in government early on so he could let the incompetence flow. And “smug little gremlin” suits the prick perfectly.

  14. Many vaccinated people are apt to see things differently, especially if they think the onus should be on members of high-risk groups to avoid situations that are conducive to virus transmission. Now that vaccines are widely available to older Americans and people with preexisting medical conditions, that argument has additional force.

    The minimal inconvenience of wearing a mask during a trip to the grocery store (assuming the store no longer requires it) is a pretty easy way of reassuring people who are especially vulnerable to COVID-19 but have not managed to get their shots yet, especially since they ordinarily have no way of knowing who has been vaccinated. But as time goes by and daily new cases continue to drop, vaccinated Americans are apt to lose patience with people in high-risk groups who have the opportunity to get vaccinated but fail to do so.

    Which is pretty much what I’ve been saying for several months. I’m happy to help out and wear a mask until any oldster who wants vaccine has gotten it, and even until I’ve gotten it, but after that, I’m wondering why I need to wear a mask for those who don’t believe in vaccines?

    1. (Given my age and health, I’m in the “everybody else” at the end of the line group. i.e. I’m willing to keep up the mask thing another few months, but expecting to be celebrating Independence day getting some sun on my face.)

  15. I hate Greta Thunberg.

    1. I would too, but having been in the service, I made a vow not to stand in long lines again.

    2. Why? She’s hawt.

    3. That makes you ridiculous. Think about it.

  16. “Contrary to What the CDC’s New COVID-19 Advice Implies, There Is Strong Evidence That Vaccination Curtails Virus Transmission”

    Will social media let you post a story with a headline like that?

  17. Always taking the most risky position on personal hygiene during a pandemic might seem like the libertarian thing to do, but ask yourself why you are a libertarian if it means you have to constantly whine about hygiene measures.

    And since we do have Trumpers, clearly we must err on the side of restrictiveness. They are convinced that being asked not to get their disgusting germs on other people is basically slavery. So… more public education?

    1. It’s not about taking the most risky position. It’s about opposing centralized mandates and control of the public. The federal government and particular the CDC can put up all the signs they want recommending people wear rainbow colored beanie caps and plaid suspenders for all we care, but to actually police the free movement of people and enforce requirements on how they dress? (to be fair, to its credit the federal government, I will admit, has not mandated masks anywhere, they’ve just leaned on the states to do that and I would expect that every libertarian opposes that as well. An injustice committed by the states is not okay just because the feds aren’t doing it)

      It’s not a matter of whether the CDC’s advice is right or wrong (though there is plenty to criticize about it). It’s about the belief that individuals are best able to figure out how to arrange their lives in the safest and most profitable manner. Some moronic politically motivated hack at a government agency, too lazy and stupid to get a job in the private sector, will never be able to figure out how to make grandma safer than grandma can. Freedom allows people to make bad choices, but it doesn’t force bad choices upon them.

      1. Except, since the CDC doesn’t have the authority to issue mandates, this is just a recommendation. If it were a mandate, all the states that don’t have mask restrictions would be in non-compliance and subject to lawsuits.

        1. I addressed that in my post actually. Most of the pandemic oppression has been state-created rather than federally created, but the point is the same. It doesn’t matter if the central planners are in DC or in your state capitol, they have no business telling you how to be hygenic or whether your business is “essential” or whether you can evict people from your property or any of the other spectacular abridgements of freedom we’ve seen them initiate in the name of public safety.

    2. Not wearing masks is far from being the “most risky position on personal hygiene”. As a gay man who is aware of the AIDS epidemic, you should know this.

  18. This is such bullshit. Telling everyone to wait for a vaccine was stupid and awful enough. Now there are vaccines that seem to work pretty well. That’s the best we’re going to do. Stop being fucking insane! With the old and sick vaccinated, this really is less of a danger than most flus.

    1. Don’t forget that the vaccines were delayed for months by the FDA. Government has failed us at every turn during the last year…. which isn’t at all surprising.

      1. They have done a lot more than fail us. They have perpetrated on us perhaps the greatest assault on human rights and freedom ever.

  19. I have to think that virus transmission isn’t the only thing going through the CDC’s collective mind on this. Since mask-wearing became a political statement, there are social implications to any policy announcements. For example, if every idiot who is tired of masks stops wearing a mask, claiming they are already vaccinated, we would see another spike in transmission. A lesser concern would be the opposite case where people who are vaccinated get harassed for not wearing a mask — this isn’t a covid risk, but could be a mental health risk.

    1. we would see another spike in transmission

      Not necessarily true. A lot of communities are at or near herd immunity now. We just saw the last spike in the US. Prior lockdowns didn’t prevent it. They just stupidly made sure that it happened during the winter flu season. But now it’s trending down because most everyone who’s going to get this virus has had it. Masks don’t matter any more from the perspective of preventing mass infection, if they ever did.

  20. Well duh! Virus transmission is from people who have the virus to others. Vaccination does not prevent the virus, as it’s not a shield condom. Vaccinations triggers the immune system to prepare for the virus. Big difference.

    So one can catch the virus, but the body then eliminates it. But the time between breathing in the virus, and the body eliminating it, is a positive finite period, during which the virus can still be re-transmitted.

    At a greatly reduced probability of course. But still a positive finite percentage.

    So let’s say the normal course of the virus is 21 days. Now let’s say th vaccination rids the body of the virus in three days, because the virus never gets a foothold. That’s automatically makes the person 1/7th less infectious. But it’s less than that because the viral load is much less (less virus in snot to sneeze out). Maybe it’s only 1/70th chance. That’s still a positive number. But it’s more like 1/700th chance. A minuscule but positive number.

    So what we have is a really small number. But it’s still a positive number. Both sides are correct. The CDC is correct in a technical sense. Even one virus particle is enough to infect someone else. But Sullen is essentially correct, in that the danger from an immunized person is safe enough for normal social interactions.

    The big purpose of vaccinations is not to protect the person getting vaccinated, but to protect the public at large by attaining herd immunity. And we won’t get there until we get around 90% vaccinated or recovered.

    So go get vaccinated if you can, if you want to be back in the social flow. It’s not a guarantee but it’s what well let the social flow happen so we can rejoin it. Be an anti-vaxxer and you’re just a selfish asshole wanting to keep everyone locked down. Don’t be that asshole.

    1. “…Be an anti-vaxxer and you’re just a selfish asshole wanting to keep everyone locked down…”

      Fuck off, slaver.

    2. One the most vulnerable are vaccinated, which we are pretty close to, everyone needs to go back to normal. Or leave the rest of us the fuck alone. With the vaccine for those who more reason for concern, it really is just another flu-like thing.

  21. This is just a game of puppet master being played by the CDC. They know there are enough sheeple out there to put the votes into the right pockets. Place fear into the people and you have even further control over them.

  22. “asymptomatic infections”… As in, people who aren’t fucking SICK??????????
    You’re an imbecile Sullem!

  23. “Contrary to What the CDC’s New COVID-19 Advice Implies, There Is Strong Evidence That Vaccination Curtails Virus Transmission”

    If it didn’t what would be the point of the vaccinations? Maybe Reason can explain?

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