Time To Travel: CDC Study Shows Vaccines Prevent Both Infections And Spread

We already know that approved vaccines are highly effective protecting you against Covid-19, especially for serious cases. We now have great data showing they protect others from you as well. In other words – if you’re vaccinated you aren’t just preventing yourself from getting sick, you’re preventing yourself from being a carrier of the virus too.

From the New York Times: New CDC study of the Pfizer and Moderna vaccines show they prevent transmission as well as protection from symptomatic Covid

There has been debate over whether vaccinated people can still get asymptomatic infections and transmit the virus to others. The study, by researchers at the Centers for Disease Control and Prevention, suggested that transmission may be extremely unlikely, as infections were so rare.

There also has been concern that variants may render the vaccines less effective. The study’s results do not confirm that fear.

The CDC studied vaccinated health care personnel, first responders and other essential workers between December and March. Study participants had received either the Pfizer-BioNTech or Moderna vaccines. They found,

  • 80% effectiveness against infection two weeks after the first shot but before the second
  • 90% effectiveness against infection two weeks after the second shot.

Someone vaccinated with two shots of an mRNA vaccine highly unlikely to have even an asymptomatic case of Covid-19, meaning they aren’t likely to have it and spread it without feeling sick. In other words these vaccines are nearly as effective against asymptomatic disease as they were found to be effective against symptoms in Phase 3 trial data.

Some have suggested that trial data may overstate the effectiveness of the vaccines, because those trials occurred before current variants of the virus had become widespread. However this study, testing participants for Covid-19 weekly, occurred during spread of current variants.

If you’ve been vaccinated you can probably travel. You aren’t likely to get or spread the virus. And it’s reasonable for families with young children to consider travel as well.

Your risk isn’t zero but we do things that entail some risk all the time, like driving in a car. With a 90% reduction in risk, the science supports a judgment to travel if that’s something you value.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community InsideFlyer.com, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. 1 out every 25 that were in the hospital for Covid since December in the U.K. were people who got vaccinated but could not wait for the immunity to kick in. I am on day 16 for the first dose, second one on Saturday. Fifteen more days and I should be good to go.

  2. You say these studies “show.” The article correctly more qualified language, saying it “suggests” or “is likely.” That difference matters a lot. This kind of misreporting often leads to a lack of trust. If you report on public health please follow science and follow the lead of scientific experts.

  3. Any indication that they will now drop the per-arrival test requirement for fully vaccinated travelers?
    Currently US citizens are required to have a negative covid test within 3 days of arrival.

  4. You lying [redacted -gl]. The CDC literally today reiterated essential travel only.

    [redacted -gl].

  5. To the commenter whose extreme profanity I redacted, I wrote this post before the CDC Director’s statement or else I would have pointed out how her claim against travel is inconsistent with the data from her own agency. I just finished a post about that statement which has not yet published.

  6. The issue with statements like “time to travel” is

    – Unvaccinated people are taking these statements as a sign the they can relax their own mitigation efforts. Basically people are getting sloppy in their mask wearing, hand washing, avoiding unnecessary indoor dining, etc. I am seeing this in NYC amongst clearly unvaccinated people (young people, etc), and it is causing more spread
    – Vaccine “free riders” are trying to avoid getting the vaccine and depending on others to do so. No, you shouldn’t start traveling now because others are getting vaccinated. Barely 20%-25% of people have been vaccinated so far depending on who you believe

    It is time to book and plan travel – but book your vaccine appointment first, and continue to mask up 14 days after your second shot (and continue to mask up in spaces like airplanes regardless)

    We are almost there, don’t screw it up

  7. I was thinking the same thing Gary but without the profanity. I eagerly await your new post about the comments the CDC director made. She is not following her own science. Shameful. But Biden asking that masks stlll be worn by everyone is a good idea for another 90 days so that virtually anyone 16 and older has the opportunity for at least one shot. After 90 days, that vaccine passport on everyone’s phone should be good enough!

  8. Hey folks let’s be civil. Gary is doing the best he can to help us determine our future travel plans. Knock it off. You are NOT paying for his research or his time.

  9. Good god. The CDC director with her crocodile tears asking people not to travel. She has no credibility. And should be out of a job immediately. Her statement makes we want to book MORE travel. She can go to hell.

  10. So envious of Brian…obviously he doesn’t know anyone who has gotten seriously ill or died from COVID.

    I hope someone he loves never gets intubated.

  11. People have held back on so much stuff for so long that many seem unable and unwilling just give it 3 months more to try to minimize the chance of the country being ground zero for an even more troubling variant that keeps this pandemic dragging out longer and longer with all the damage that comes with it.

    The US vaccine manufacturers are going to be kept busy way more and for far longer with all this “it’s time to travel” attitude.

  12. This will never end….well I guess it will have to eventually. Don’t worry though, the Derek Chauvin trial should be over soon and we’ll be able to get our summer of murder and destruction underway.

  13. @Jeff
    You likely won’t be killed by a meteorite crashing through your bedroom ceiling either. If Gary told me that I probably won’t die in that manner, I would be pretty comfortable accepting that as truth.

  14. You just have to love the ones that come out of the woodwork to tell us all to stay home – I mean the ones that write it here. Anyone with much of a brain should realize from data already available that if the protection was so high, vaccinated people were unlikely to spread it. I understand, to a point, the CDC trying to keep us focused on masks, social distancing, etc. Everyone can’t be vaccinated yet but soon it should be available to everyone over 16. However, if you are fully vaccinated (meaning 2 weeks after the second shot), GO, GO, GO – if you want to.

    They can not hold everyone vaccinated to the same standard as everyone who is not vaccinated. It either works or it does not and if it does not, why would we bother getting it? What would be the point? I have 3 weeks left before I am fully vaccinated and I fully intend to resume my life shortly after that. If they want hesitant people to get the vaccine, they need to let them know that it has benefits.

  15. FYI, the NYTimes isn’t a news source I trust anymore. It’s above the NY Post, but not by much.

    Please quote independent people and research, not sensationalist media.
    Their front page is like an opinion page – it’s not news anymore, just a soap box.

  16. Well, it will be up to each individual country to protect its citizens from people like you.

  17. Yet the testing data shows that a new wave is building, so hard data (not some conjucture) loudly screams that it’s still TIME TO STAY HOME if we want to exit the pandemic.

  18. @George – NYT has 130 Pulitzers and counting. And is a thriving entity increasing it’s staffing.

    NY Post…uh it might be 0. Not exactly credible.

    Watch Newsmax or OAN to your heart’s content.

  19. Jake, the twice vaccinated are flat out not going to stay home. The train has already left the station and its filled with vaccinated passengers! Or, more accurately, planes are filling up rapidly with older people! The only realistic way to reduce the next wave is, for the next 90 days, to get as many arms as possible jabbed with the vaccines and for everyone to wear a mask when away from home and in proximity to others indoors and on planes and trains!!

  20. Pete- please stay home forever. I don’t need people like you packing flights and taking hotel rooms I might want. You keep living in fear that someone you know might DIE, and therefore your life should be put on hold. Good grief.
    Now excuse me while I check in for my flight for my vacation this week.

  21. @Brian – Agreed re: the CDC director. This dingbat is literally begging people to listen to her because she knows people aren’t listening to her anymore.

    @GUWonder – “People have held back on so much stuff for so long that many seem unable and unwilling just give it 3 months more”

    Yes, that’s exactly right. They’ve been telling us “just a little while longer” for a freaking year now. Why should any of us believe them at this point? Yes, we have a vaccine now, but they’re still saying the EXACT SAME THING they were saying last year.

    @Pete – I can’t speak for the other Brian, but I don’t know anyone who has gotten COVID.

  22. There is no Covid test that is accurate. All they check for is genetic material. You have Covid if you have the specific symptoms. Cases are just to get you scared, then they tell you to go home and if it gets really bad go to the hospital. No other advice given. Ridiculous.

    The injection you are getting does not give you immunity to SARS-CoV-2 virus. Period! It may give you an antibody against a spike protein that is a manufactured synthetic protein that may or may not be specific to a SARS-CoV-2 virus or any virus. The mRNA that is producing the synthetic manufactured spike protein is giving you the potential for an antibody against the spike protein but not against the SARS-CoV-2 virus. If anything it is creating antibodies against multiple areas of our own body like the brains, liver, heart, blood, etc. There is NO injection against the SARS-CoV-2 virus…only against the synthetic spike protein.

    There are thousands dying and tens of thousands injured from the vaccines worldwide. Look up the various country databases to see the facts not just the American VAERS system. UK reporting 594 dead and 404,525 injuries. Exactly as the MHRA predicted when they put out an advertisement last year for an “AI software tool to process the expected high volume of Covid-19 vaccines Adverse Drug Reactions (ADR)”. Look it up! They knew it last year!!

    As far as “avoid indoor gatherings, properly wear good quality masks, and get vaccinated as soon as possible”… I can say that I and many of us around the world have completely ignored that since early 2020. We have had guests in our home from one of the worst reported cities with cases of deaths in America. They have stayed over, had their children sleep in the same bed as our children, we mingle with the 1200 people in our community without masks, have people over for dinner, go out to local stores with a useless mask on to get in the door then immediately below the nose it goes, etc…. None of us got sick. I know some people around the world who got sick but recovered. All of the people I know are taking the recommended supplements, exercising, not listening to mainstream news and eating healthy foods. This is not to say people are not dying from Covid. They are….just like they die from Heart Disease, Stroke, Cancer, etc. But this “thing” has a much greater survivability IF you get it.

    There are lawsuits around the world, lockdown protests around the world, people who will not submit to a gene manipulation experimental injection and will always be plenty of businesses, cities and states who will do business with the unvaccinated. Look forward to the legal challenges of a vaccine “passport”!

    As a pro vax doctor recently said, who worked for the horrible Gates Foundation and still thinks highly of vaccines in general, never, ever introduce a vaccine during a pandemic. It will only make it that much worse.

  23. Unfortunately, vaccines work best when everybody has them. We are nowhere close to everybody having them and the anti-vaxxer people may derail the whole thing and keep the pandemic going until there is a strain that evades the vaccine. What they should do is mandate vaccination for people who want to fly unless they have medically documented reasons they can’t take vaccine.

  24. ” The train has already left the station and its filled with vaccinated passengers! Or, more accurately, planes are filling up rapidly with older people!” Actually the virus is spreading across the country in young unvaccinated people who are travelling. I do find it hysterical in the limited cases when I hear high risk old people who spent a year telling us we all had to lockdown to protect them rushing to travel the second they get the vaccination before anyone else can get it.

  25. “Any indication that they will now drop the per-arrival test requirement for fully vaccinated travelers?” they should drop that requirement. If anything it will give people more of a motivation to get vaccinated.

  26. The CDC is using, and has been using, a fallacy of logic called the Appeal to Fear. Relying on its ethos, it preys on people’s fears of disease and death. They revere the CDC as a god now. Since when does science say “I’m scared… I feel a sense of impending doom,” as Walensky did today? These carefully crafted, emotionally charged words are designed to invoke fear, not report science. We keep being told “just a bit longer, just hang on a bit longer.” Instead of seeing any restrictions relaxed, we see a political battle, conservative versus liberal, and so instead, restrictions have tightened at the national level. “Get the vaccine!” they cry (I have, by the way, and am fully vaccinated), but you still have to test, wear masks, and do everything as if you are not because, “psych! We don’t fully believe it yet. Except we do. Maybe kinda sorta. So get it, but it won’t change anything at all for you.” With messages like this, and “Science” contradicting actual science from its own research, I think we maybe need to have a CDC audit of data.

    By the way, Gary, did you notice that up until a few weeks ago, the CDC reported DAILY averages on its website, and then suddenly without warning or explanation it changed to 7 day averages? The day that changed the daily average case count was down to 18.8. It was steadily dropping, and I know because I was doing an analysis project with my university students and taking screenshots every day. I really want an outside audit of the case count data. I am beginning not to trust a lot of this. They have two sides of their mouth.

  27. A rude awakening awaits you all:

    “The planet could have a year or less before first-generation Covid-19 vaccines are ineffective and modified formulations are needed, according to a survey of epidemiologists, virologists and infectious disease specialists.

    Scientists have long stressed that a global vaccination effort is needed to satisfactorily neutralise the threat of Covid-19. This is due to the threat of variations of the virus – some more transmissible, deadly and less susceptible to vaccines – that are emerging and percolating.

    The grim forecast of a year or less comes from two-thirds of respondents, according to the People’s Vaccine Alliance, a coalition of organisations including Amnesty International, Oxfam, and UNAIDS, who carried out the survey of 77 scientists from 28 countries. Nearly one-third of the respondents indicated that the time-frame was likely nine months or less.”

  28. I’ve been traveling regularly, international and domestic, since the pandemic began and I don’t plan to stop or slow down.

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