Thank you, Dr. Jetelina. This is very useful information. It’s reassuring that having six vaccinations for Covid-19 lessen my odds of getting long covid. Knowing a bit more about how hour plus exposure time is where transmission tends to happen is also helpful. I’m glad I still have plenty of masks and rapid at-home tests. The one question I have is the one you raised—when to test, especially when symptoms may “just” be slight congestion and fatigue.
I don't usually have a criticism, but this statement needs re-visiting: "Quick passersby at a grocery store are far less risky than staying in a house with someone infected. " Too many people are going to interpret this to mean little to no risk and forget that this is in comparison to the much larger risk in a home where you are likely unmasked and spending hours.
You should NEVER pop into the the Walmart or where ever else you like to pop, without a mask. Let's not forget the obscure finding from Australian health authorities who documented a FIVE-TEN SECOND passing contact as a source of infection at a time when this disease was orders of magnitude less infectious. https://www.theguardian.com/world/2021/jun/27/delta-covid-variant-may-be-edging-race-against-vaccines
[Update: Thanks to Martin for finally putting this story from Australia to sleep. It apparently is a result of very sloppy work and is not true. However, this does not mean that the time you spend in a store unmasked is going to work out well for you and should most definitely be avoided, especially if your dash includes standing in line to pay. Don't do that.
Unless you have the ability to see virus, as in clouds of cigarette smoke, your best bet is to mask indoors each and every time.]
But there have been more than enough stories of infections picked up more recently by going unmasked for "just a minute" into the viral soup of local commerce. Do not let the above finding she wrote about mis-lead you or others into thinking "quick" means zero. It does not.
I took that less as minimization, and more as a suggestion of where to devote one's efforts. If household spread is more of a driver of case counts than transient encounters, then it makes sense to aim more towards contingency planning. I made a conscious choice to live alone for most of the pandemic, despite not being exceptionally cautious, and managed to dodge it until October 2023.
I'm curious to know what your interpretation of "acting on it" might be. I wear an N95 mask on public transportation, when running essential errands, and in medical offices.
It definitely is not controversial here, however some of us might mis-read what was written and think they can just dash in to a store unmasked. Not many of us, but a few.
That five-ten second "passing contact" incident was unsourced conjecture, some of the worst reporting during the pandemic. All that was known was that one of the two likely had COVID at the time, and the other developed it shortly after.
They were both in a public area, and no samples were taken or follow-ups - one person told this anecdotal story to the press and they kept circulating even though it was never proven that this is how the second guy got COVID. He was in a public building and may have contacted it elsewhere there, or may have contracted it earlier in the day from a different location, or even the day prior.
A few scientists called out the harm this clickbait conjecture caused, but it was too late - now this bogus story still circumstances.
Also, your comment is "yet again" an example of someone criticizing a scientist for accurately reporting what a study showed, simply because it contradicts what you already believe.
You do not know better than Katelyn, and I'm over civilians thinking they know better than our scientists. The study she's quoting indicates most transmission isn't swift. That's good news. It's not a zero chance that you can spread it sooner than the mean, but she also never said it was.
Whoa...it's a bit of a leap there to go from reporting an inaccurate story to then concluding my original comment therefore must be some kind of criticism as in attack against the author. It's just an editing criticism, that this particular wording could be mis-interpreted by some to mean that it's perfectly okay to dash into a store or where ever. That is not a good idea. As for the Guardian report, I'm very glad to get your further information. I wrote to health authorities for further supporting evidence and was never given the source. The link you provided below is great. I asked a lot of people about this and didn't get far. BTW, yes you can become infected with a quick dash into a highly infectious environment. I'll see if I can edit my original comment to get rid of the Australian reference.
I get what you're saying, but the unvaccinated, COVID-minimizing people in my life 1) won't read this because they're busy pretending COVID is over (until they get it for the 2nd or 3rd or even 6th time) and 2) would be impervious to any caveats or warnings you could attach to this information.
As a COVID-naive person (as far as I know) who tries to make data-driven decisions, I want to know this information. Am I going to run out to Target unmasked right now, when approximately 4% of people are infectious (Mike Hoerger's estimate)? Heck no. But when numbers are low over the summer and I want to take my kid to get ice cream but I drop my mask on the ground? Yeah, I might. Or maybe I'll go somewhere with a drive-thru or have my wife grab me something while I wait outside. But it will be a more informed decision.
Thank you. Really looking forward to the Long Covid update next week.
I really wish the CDC would be honest about contagiousness period. Too many people seem to believe that they’re safe after 5 days even if they’re still testing positive. I’d be curious what the average is now, if peak viral load is happening later.
Glad to know my multiple vaccinations provide added protection. I had Covid last summer and it proved to be mild. I am sure Paxlovid helped, as well. Too bad the anti-vax crowd keeps spreading disinformation based on nothing.
Thanks, as always, for keeping us updated so we can make informed, researched-based decisions.
Question about rapid tests/viral load: If the tests aren’t showing as positive until later in the course of infection (when viral load peaks), does that mean that a negative test (and cadence testing) earlier on indicates you aren’t infectious/as infectious as later? We have a group of friends using the “Osterholm Protocol” for meeting up more safely: negative rapid test, no symptoms, and no know COVID contacts. Is the testing piece still appropriate? Or should it be adjusted somehow? Thanks for your guidance!
What a great question! If you have no symptoms, the utility of an antigen test is questionable. Two tests 48 hours apart will catch 39% of asymptomatic cases (it's much lower with just one test). So, personally, I don't do asymptomatic testing anymore, given the cost.
My understanding is that rapid antigen continues to be a proxy for 'Am I contagious right now,' so testing just before a gathering is a good practice. Today's test won't tell you if you are going to light up a test tomorrow, but it's a bit of reassurance for a window of time today.
I feel like requiring tests before in person gatherings has a value that goes beyond the accuracy of the test - you're communicating, in no uncertain terms, that it's not acceptable to bring Covid to the party.
Sadly not true. The likelihood of a positive test with no symptoms is quite low.
People test positive after gathering with negative tests and spread covid all the time.
While you may catch an asymptomatic carrier now and then, it’s probably an exception.
I wouldn’t skip the test, just recognize it’s limitations. During times of high prevalence, such as now, the risk goes up. Essentially the test and it’s effectiveness (statistically) is actually dependent on other factors.
We do need layers and caution to navigate this mess. It's possible that when we see success with test-to-gather, additional layers played a role; or when testing fails, it was an error like testing too far in advance or not being mindful of shared spaces where virus can linger. (We don't hear anecdotes about the times test-to-gather worked, because we tend to report when things backfire. Even Dr. O forgot that virus can linger in an elevator, the likely chink in his test-to-gather armor.)
Michael Mina (whose research informs the guidance for asymptomatic people to test 3x) and others continue to advocate that rapid tests have the capacity to identify infectious people, which is different from identifying a positive. It seems to be limited to a short time frame, as we see when citizen scientists test several times a day to document their experience.
Yes to layers. Yes to air cleaning and judicious mask use.
Welp. I had a weird sticky feeling in my throat last month. I tested- both nose and throat- negative. My physician and virologist friends decided to come over anyway. If anyone could make a choice for themselves, they can. Had it been layperson friends I would have cancelled. And then next morning after some coughing overnight (and oddly talking in my sleep- not ever before noted by spouse) I tested positive and 4 days later spouse and the person directly across from me at dinner did as well.
And I swab well (unpleasant)- this is not user error. These stories dominate what I heard from others over the last 3+ years. We love evidence based medicine but when you are smacked in the face daily with different findings, it’s hard to ignore. We think we had an asymptomatic exposure but who knows. Those small fleeting exposures... reminds me of April 2020. It was just in the air. Despite what everyone was told.
This is what is frustrating - how are we careful without isolating any time we feel a tickle or just wearing masks 100%? I don't judge anyone that takes extra caution they feel comfortable with - just feels like there's no way to live a life without this constant wait for the other shoe to drop. 😞
"On the day of infection onset, rapid tests detected almost 60% of infected participants who had COVID-19 symptoms, but only 10% of those who didn't. However, repeating the test 3 times, 48 hours apart, led to detection of infections in 75% of asymptomatic participants". https://www.nature.com/articles/d41586-023-02254-9
It feels like those are generous numbers depending on the day of testing, the immunity of the testee and of course other confounding variables. I don’t offer rapid Covid testing (Ag) in my office due to the low pick up and the interpretation it is negative vs NOT DETECTED. I just do PCRs.
I haven't seen the structure of the study, so I am not in a position to feel one way or the other about the results. It's great you do PCR! Do you include the cycle count or only on request because it raises too many questions that then take a lot of effort to answer?
Dr. Jetelina, I worry about the studies cited for several reasons:
1. One of the studies was funded by Pfizer, which has a vested interest in increased vaccine uptake.
2. More importantly, the data set from these studies ends either on 12/5/23 or 12/10/23 at the latest, depending upon which of the studies we're considering, with most of the data coming from ca October and November of 2023. That means that JN.1 had not reached prevalence in our population.
According to other info I've read (sorry, I don't have the citations offhand, but they were from peer reviewed studies) there is a concern that vaccinations that are not well-matched to predominant variants e.g. an XBB 1.5 targeted vaccine encountering JN.1, where such variants contain rather different sets of mutations, can result in a negative impact on T-Cell production and overall resistance to infection from these newer variants.
I fear that we are just not developing our vaccines quickly enough to fight this virus, which is a failing of our government's policies, but may be a losing battle even with the best efforts.
What do we do, then? Unfortunately, the solution (short term, at least) may be that we have to revert to greater mitigation measures, including mandatory masking, shutdowns of varying degrees, improved indoor air quality/ventilation, and creative methods for remote work/learning to avoid congregate settings. Of course, the political forces, motivated by economics, don't seem to be willing to go down this path.
I'd be curious to hear your response to these concerns and proposed possible solutions.
Thank you! A very good infectious disease physician at our state health department tried to get the epidemiologist modeler to say that Covid was seasonal at our monthly meeting about 2 months ago--I give them so much credit for still having a provider meeting--and the following month, it was clearly refuted by another physician right up front. As the pandemic feels interminable and there is so little data--your calm, evidence based information is appreciated more than ever.
My struggle is risk mitigation/protection vs isolation and this helps so much.
Thanks, once again, for continuing to plug away. At least the choir is listening. The information on viral load peaking, transmission, and non-seasonality was particularly interesting to me. Public health requires so much calm perseverance in the face of terrible things! Thank you.
Again, the study measuring vaccine effectiveness is very flawed and biased. These "studies" are the equivalent of big pharma propaganda, not useful "science"
1) Study period is only 2 months, what the data would show beyond that is anyone's guess. 2 months is a very short time period that tells you next to nothing.
2) First 7 days after injection is excluded...why? Once the shot goes into your arm, you should be considered vaccinated.
3) Only measures against COVID-19 hospitalizations (however that is determined) and not all-cause hospitalizations.
Hi Paul. Thanks for your response. I know we don't see eye to eye on this, and I don't think that's going to change. But some responses regardless:
1. Yes, unfortunately, we are at the mercy of time. Time is a limitation out of our control.
2. It's excluded because it takes 2 weeks for the immune system to be activated. It's not "automatic" protection. This is a common misconception with vaccines.
3. Not just hospitalizations were measured, but ED and outpatient use were also tested. We cannot do all hospitalizations (in the US) because we don't have a vaccine registry like Denmark has, for example. Perhaps you can help advocate for better public health data so we can test things like this. UK has a great analysis of vaccine impact over time against all-cause death. The effect is still very clear.
4. This would be best in the ideal world but it hasn't been done as there are serious ethical reasons for doing an RCT with high-risk patients, like those over 60.
5. I think this was definitely a bias earlier in the pandemic, where people vaccinated were more likely to mask. These days, there may be small bias, but certainly not enough to explain a 70% difference.
Are we ever going to get past the conspiracy theory that claims because a pharma funds a study, that study is automatically biased pharma propaganda?
AFAIK these trials are conducted by government agencies and/or independent 3rd-party contract laboratories, insulated from manufacturer influence. Manufacturers don't want the legal exposure of defending against fraud allegations arising from putting out "biased propaganda" (even if the case ends up being dismissed after over a decade of legal expenses and bad PR, as the case against Merck for their mumps vaccine recently was - and rightly so).
Frankly. I want manufacturers to pay for all the studies done on their products. I want my tax dollars to go towards buying the products shown to work.
2) 3) Yes, understood. This is why you need to run randomized controlled trials to control for as many of these confounding variables as possible. Unless the UK analysis is accounting for healthy vaccinee bias, etc, the data tells you very little. And like all data covid-related, it needs to be age-stratified. These vaccines may reduce the absolute risk of death or hospitalization for a diabetic 70 year-old, but not for a healthy 30 year-old. The VE data is reported as relative risk ratios and not absolute risk reduction. This is done for a reason. 70% VE could be 10/3 out of a million or 10/3 out of 100
4) There are also serious ethical issues with pushing shots on everyone before/without knowing anything about efficacy or safety.
5) There's never been any evidence that wearing a mask prevents hospitalization from covid.
Again, I will come back to this. The Phase III Pfizer trial for the original shot didn't show a mortality or hospitalization benefit. No RCT has for any of the shots.
In 40 years associated with medicine, I have yet to see a perfect clinical trial. This kind of critique may be well suited to invited critique in a peer reviewed journal, but it is obfuscating to a general audience. There is broad concurrence amongst experts on the big issues, like: Get vaccinated. There is far less risk of vaccination complications than complications of the infection itself. Even partial immunity has value to the individual and the population. During high viral activity times, wear a quality mask in public. Avoid high probability exposure in times of high viral activity. If you're sick, stay home. If you're sick, get tested and take the medication to reduce duration/severity of symptoms. COVID is a bitch; so is long COVID
This is not rocket science, not particularly controversial at this point. As a population, we have rapidly become complacent again; look at the low incidence of vaccination amongst high risk populations this time around. It's no harder to get a COVID vaccine than to get a flu vaccine. I got both in the same sit, in the same arm. Other than a sore arm for a couple of days, no muss, no fuss.
Paul: I think people wouldn't take your tone as quite so hostile/troll-like if you simply dialed-down on the scare-quotes. As a New Years resolution on my end, I'll do my best to look past that pattern - but I'd like you to reciprocate by not using them.
Thank you so much for the update. I appreciate the time that you put into these. I work in healthcare and I have had multiple exposures to Covid from patients who tested later and found out they had it, and suspected Covid exposures from people who do not test and just assume that everything is "just a cold." To my knowledge, I have only had Covid once. I was wondering if Covid exposures for short periods of time act almost like a vaccine and actually keep the antibody and/or T cell response primed? I'm not suggesting that anyone should do this on purpose. I'm just genuinely curious about this.
A really good question, but exposure doesn't necessarily mean infection. We need to be infected for our immune systems, and certainly the T-cells, to be primed. I would suspect you have amazing hybrid immunity at this point, though.
I'm curious about this too. It's not the exposure alone, but could frequent exposure be resulting in infections you are unaware of, where you are asymptomatic or barely symptomatic because your immune system fights it off quickly before the virus replicates too much.
I think that this is definitely a possibility. I do test when I am symptomatic, even if the symptoms are pretty mild. What is weird is I did not catch it when other family members that I live with had it and we did not isolate either. My 2 boys and my husband each had it twice and I thankfully avoided it each time. When I actually did catch it, I have no idea where it came from. It was quite the mystery. My husband says that I'm a unicorn.
Your last post said that people develop symptoms sooner in the infection cycle now that most of us have prior exposure via some combination of vaccination and infection. That seems consistent with this post that says viral load now peaks a few days after symptom onset, instead of around symptom onset.
So i wonder if that means that antivirals like paxlovid are useful later (as compared to the starting point of "has symptoms") than they used to be, because the real starting point has to do with viral replication. It's anyone studying alternative paxlovid dosing regimens?
I've also wondered that about rebound, and if perhaps paxlovid would be more effective if it were administered for 7 days instead of 5. (Or started later, or for fewer days ... I suspect the very first study used 5 days, was found to be effective, and wonder if anyone has looked into improving that.)
The Paxlovid dosing regimen is something that frustrates me to no end. Because, no, Pfizer doesn't seem to be testing this. And it really needs to be tested. For example, I really don't think a 5-day course is enough, given the rebounding. We really need a 10-day course. However, we don't know. I think this is where FDA should pressure companies to continue to look into the efficacy of their products, especially since Pfizer is now charging $1400 a course. Rant done.
I have to respectfully disagree with the concern about "rebound" (inflammatory phase) with is the second phase of this biphasic disease. A recent study confirm that this is mild and noted in the MMWR.
"CDC examined SARS-CoV-2 rebound studies among patients who did and did not receive antiviral treatment. No consistent association between treatment and rebound was identified. The prevalence of rebound varied, depending upon host factors and the definition of rebound. Rebound symptoms were mild. No hospitalizations or deaths occurred from viral rebound." https://www.cdc.gov/mmwr/volumes/72/wr/mm7251a1.htm
I believe there are trials for 10 and 15 day courses. Will have to cite later.
I wish we'd put this "Does Paxlovid increase the risk of rebound?" debate to bed. Either it's causing it, or it's failing to stop it. An effective treatment regimen should stop the disease in its tracks so *nobody* has to miserable.
Now, let's work towards tweaking the use of Paxlovid so it works for everybody!!!
Agreed. The article I linked was co-authored by Dr David Ho who was Time Magazine’s Person of the Year in 1996 for AIDS research. He’s probably the world’s best expert on viruses.
I’d trust his research more than I trust Pfizer’s.
I also think regulators are reluctant to say anything negative publicly about drugs (and vaccines) that they’ve already approved. Face saving.
A doctor I know who does research in this area recommends taking Paxlovid up to 10 days, and stopping sooner if a person has 2 negative consecutive daily tests. This will greatly reduce the risk of rebound.
I actually corresponded with Dr. Ho via email while I had Covid in October - it gave me the courage to go for a second (10 day) round of Paxlovid after I rebounded. It worked.
I love the "up to 10 days" approach you describe - that way it lined up with the 10 day isolation period.
I think this conversation is coming to the FDA in February. I will report back, but I would not be surprised if those over 65 and *severely* immunocompromised get two Covid-19 vaccines a year.
Two vaccines/year might be helpful for vulnerable populations IF the vaccines are adequately matched to currently circulating variants. I worry that significant mutations are occurring or will be occurring that outrun the pace of development and release of new vaccines. A number of epidemiologists and ID specialists are beginning to express concerns about the efficacy of the currently available vaccine against JN.1 It seems that the data sets may be too old/small to ascertain efficacy with adequate certainty.
Based on the effect of household spread that you describe - do you think it might help "smooth" the waves if household members offset their boosters from one another? Hedging is a generally accepted risk mitigation strategy, after all.
Question: Received Novavax XBB 1.5 booster in October. Is there any data on waning yet? Or the need for re-boosting? I wear an N95 indoors, but I'm in a vulnerable age group and want as much vaccine protection as possible. Thanks!
Thank you, Dr. Jetelina. This is very useful information. It’s reassuring that having six vaccinations for Covid-19 lessen my odds of getting long covid. Knowing a bit more about how hour plus exposure time is where transmission tends to happen is also helpful. I’m glad I still have plenty of masks and rapid at-home tests. The one question I have is the one you raised—when to test, especially when symptoms may “just” be slight congestion and fatigue.
I don't usually have a criticism, but this statement needs re-visiting: "Quick passersby at a grocery store are far less risky than staying in a house with someone infected. " Too many people are going to interpret this to mean little to no risk and forget that this is in comparison to the much larger risk in a home where you are likely unmasked and spending hours.
You should NEVER pop into the the Walmart or where ever else you like to pop, without a mask. Let's not forget the obscure finding from Australian health authorities who documented a FIVE-TEN SECOND passing contact as a source of infection at a time when this disease was orders of magnitude less infectious. https://www.theguardian.com/world/2021/jun/27/delta-covid-variant-may-be-edging-race-against-vaccines
[Update: Thanks to Martin for finally putting this story from Australia to sleep. It apparently is a result of very sloppy work and is not true. However, this does not mean that the time you spend in a store unmasked is going to work out well for you and should most definitely be avoided, especially if your dash includes standing in line to pay. Don't do that.
Remember the early research and the "15 minute " rule? Don't count on that, either. https://www.npr.org/sections/goatsandsoda/2020/10/09/922385856/coronavirus-faq-whats-the-deal-with-the-15-minute-rule
Unless you have the ability to see virus, as in clouds of cigarette smoke, your best bet is to mask indoors each and every time.]
But there have been more than enough stories of infections picked up more recently by going unmasked for "just a minute" into the viral soup of local commerce. Do not let the above finding she wrote about mis-lead you or others into thinking "quick" means zero. It does not.
Aerosols linger— and JN.1 seems quite contagious.
I took that less as minimization, and more as a suggestion of where to devote one's efforts. If household spread is more of a driver of case counts than transient encounters, then it makes sense to aim more towards contingency planning. I made a conscious choice to live alone for most of the pandemic, despite not being exceptionally cautious, and managed to dodge it until October 2023.
It's for those who will come away with the wrong interpretation and not masking where they should.
I'm curious to know what your interpretation of "acting on it" might be. I wear an N95 mask on public transportation, when running essential errands, and in medical offices.
Good point, poor wording which I will correct. "Acting on it" meant going into places without a mask.
I feel like masking isn't terribly controversial in the YLE universe.
It definitely is not controversial here, however some of us might mis-read what was written and think they can just dash in to a store unmasked. Not many of us, but a few.
That five-ten second "passing contact" incident was unsourced conjecture, some of the worst reporting during the pandemic. All that was known was that one of the two likely had COVID at the time, and the other developed it shortly after.
They were both in a public area, and no samples were taken or follow-ups - one person told this anecdotal story to the press and they kept circulating even though it was never proven that this is how the second guy got COVID. He was in a public building and may have contacted it elsewhere there, or may have contracted it earlier in the day from a different location, or even the day prior.
A few scientists called out the harm this clickbait conjecture caused, but it was too late - now this bogus story still circumstances.
Also, your comment is "yet again" an example of someone criticizing a scientist for accurately reporting what a study showed, simply because it contradicts what you already believe.
You do not know better than Katelyn, and I'm over civilians thinking they know better than our scientists. The study she's quoting indicates most transmission isn't swift. That's good news. It's not a zero chance that you can spread it sooner than the mean, but she also never said it was.
Whoa...it's a bit of a leap there to go from reporting an inaccurate story to then concluding my original comment therefore must be some kind of criticism as in attack against the author. It's just an editing criticism, that this particular wording could be mis-interpreted by some to mean that it's perfectly okay to dash into a store or where ever. That is not a good idea. As for the Guardian report, I'm very glad to get your further information. I wrote to health authorities for further supporting evidence and was never given the source. The link you provided below is great. I asked a lot of people about this and didn't get far. BTW, yes you can become infected with a quick dash into a highly infectious environment. I'll see if I can edit my original comment to get rid of the Australian reference.
https://www.news.com.au/lifestyle/health/australias-fleeting-virus-spread-claim-disputed/news-story/fe52826673e681dd8acd3d23486f98b8?amp=
I get what you're saying, but the unvaccinated, COVID-minimizing people in my life 1) won't read this because they're busy pretending COVID is over (until they get it for the 2nd or 3rd or even 6th time) and 2) would be impervious to any caveats or warnings you could attach to this information.
As a COVID-naive person (as far as I know) who tries to make data-driven decisions, I want to know this information. Am I going to run out to Target unmasked right now, when approximately 4% of people are infectious (Mike Hoerger's estimate)? Heck no. But when numbers are low over the summer and I want to take my kid to get ice cream but I drop my mask on the ground? Yeah, I might. Or maybe I'll go somewhere with a drive-thru or have my wife grab me something while I wait outside. But it will be a more informed decision.
The target audience for my comment is right here. The intent is to make sure people don't come away with the wrong idea.
Thank you. Really looking forward to the Long Covid update next week.
I really wish the CDC would be honest about contagiousness period. Too many people seem to believe that they’re safe after 5 days even if they’re still testing positive. I’d be curious what the average is now, if peak viral load is happening later.
Glad to know my multiple vaccinations provide added protection. I had Covid last summer and it proved to be mild. I am sure Paxlovid helped, as well. Too bad the anti-vax crowd keeps spreading disinformation based on nothing.
Thanks, as always, for keeping us updated so we can make informed, researched-based decisions.
Question about rapid tests/viral load: If the tests aren’t showing as positive until later in the course of infection (when viral load peaks), does that mean that a negative test (and cadence testing) earlier on indicates you aren’t infectious/as infectious as later? We have a group of friends using the “Osterholm Protocol” for meeting up more safely: negative rapid test, no symptoms, and no know COVID contacts. Is the testing piece still appropriate? Or should it be adjusted somehow? Thanks for your guidance!
What a great question! If you have no symptoms, the utility of an antigen test is questionable. Two tests 48 hours apart will catch 39% of asymptomatic cases (it's much lower with just one test). So, personally, I don't do asymptomatic testing anymore, given the cost.
My understanding is that rapid antigen continues to be a proxy for 'Am I contagious right now,' so testing just before a gathering is a good practice. Today's test won't tell you if you are going to light up a test tomorrow, but it's a bit of reassurance for a window of time today.
I feel like requiring tests before in person gatherings has a value that goes beyond the accuracy of the test - you're communicating, in no uncertain terms, that it's not acceptable to bring Covid to the party.
Sadly not true. The likelihood of a positive test with no symptoms is quite low.
People test positive after gathering with negative tests and spread covid all the time.
While you may catch an asymptomatic carrier now and then, it’s probably an exception.
I wouldn’t skip the test, just recognize it’s limitations. During times of high prevalence, such as now, the risk goes up. Essentially the test and it’s effectiveness (statistically) is actually dependent on other factors.
We do need layers and caution to navigate this mess. It's possible that when we see success with test-to-gather, additional layers played a role; or when testing fails, it was an error like testing too far in advance or not being mindful of shared spaces where virus can linger. (We don't hear anecdotes about the times test-to-gather worked, because we tend to report when things backfire. Even Dr. O forgot that virus can linger in an elevator, the likely chink in his test-to-gather armor.)
Michael Mina (whose research informs the guidance for asymptomatic people to test 3x) and others continue to advocate that rapid tests have the capacity to identify infectious people, which is different from identifying a positive. It seems to be limited to a short time frame, as we see when citizen scientists test several times a day to document their experience.
Yes to layers. Yes to air cleaning and judicious mask use.
Welp. I had a weird sticky feeling in my throat last month. I tested- both nose and throat- negative. My physician and virologist friends decided to come over anyway. If anyone could make a choice for themselves, they can. Had it been layperson friends I would have cancelled. And then next morning after some coughing overnight (and oddly talking in my sleep- not ever before noted by spouse) I tested positive and 4 days later spouse and the person directly across from me at dinner did as well.
And I swab well (unpleasant)- this is not user error. These stories dominate what I heard from others over the last 3+ years. We love evidence based medicine but when you are smacked in the face daily with different findings, it’s hard to ignore. We think we had an asymptomatic exposure but who knows. Those small fleeting exposures... reminds me of April 2020. It was just in the air. Despite what everyone was told.
This is what is frustrating - how are we careful without isolating any time we feel a tickle or just wearing masks 100%? I don't judge anyone that takes extra caution they feel comfortable with - just feels like there's no way to live a life without this constant wait for the other shoe to drop. 😞
It's definitely a problem:
"On the day of infection onset, rapid tests detected almost 60% of infected participants who had COVID-19 symptoms, but only 10% of those who didn't. However, repeating the test 3 times, 48 hours apart, led to detection of infections in 75% of asymptomatic participants". https://www.nature.com/articles/d41586-023-02254-9
It feels like those are generous numbers depending on the day of testing, the immunity of the testee and of course other confounding variables. I don’t offer rapid Covid testing (Ag) in my office due to the low pick up and the interpretation it is negative vs NOT DETECTED. I just do PCRs.
I haven't seen the structure of the study, so I am not in a position to feel one way or the other about the results. It's great you do PCR! Do you include the cycle count or only on request because it raises too many questions that then take a lot of effort to answer?
How is "the day of infection onset" defined for all those people who had no symptoms?? It seems unknowable.
"The Osterholm Protocol" sounds like a great title for my next spy novel
Dr. Jetelina, I worry about the studies cited for several reasons:
1. One of the studies was funded by Pfizer, which has a vested interest in increased vaccine uptake.
2. More importantly, the data set from these studies ends either on 12/5/23 or 12/10/23 at the latest, depending upon which of the studies we're considering, with most of the data coming from ca October and November of 2023. That means that JN.1 had not reached prevalence in our population.
According to other info I've read (sorry, I don't have the citations offhand, but they were from peer reviewed studies) there is a concern that vaccinations that are not well-matched to predominant variants e.g. an XBB 1.5 targeted vaccine encountering JN.1, where such variants contain rather different sets of mutations, can result in a negative impact on T-Cell production and overall resistance to infection from these newer variants.
I fear that we are just not developing our vaccines quickly enough to fight this virus, which is a failing of our government's policies, but may be a losing battle even with the best efforts.
What do we do, then? Unfortunately, the solution (short term, at least) may be that we have to revert to greater mitigation measures, including mandatory masking, shutdowns of varying degrees, improved indoor air quality/ventilation, and creative methods for remote work/learning to avoid congregate settings. Of course, the political forces, motivated by economics, don't seem to be willing to go down this path.
I'd be curious to hear your response to these concerns and proposed possible solutions.
Thank you for your important work!
Thank you! A very good infectious disease physician at our state health department tried to get the epidemiologist modeler to say that Covid was seasonal at our monthly meeting about 2 months ago--I give them so much credit for still having a provider meeting--and the following month, it was clearly refuted by another physician right up front. As the pandemic feels interminable and there is so little data--your calm, evidence based information is appreciated more than ever.
My struggle is risk mitigation/protection vs isolation and this helps so much.
Thanks, once again, for continuing to plug away. At least the choir is listening. The information on viral load peaking, transmission, and non-seasonality was particularly interesting to me. Public health requires so much calm perseverance in the face of terrible things! Thank you.
Again, the study measuring vaccine effectiveness is very flawed and biased. These "studies" are the equivalent of big pharma propaganda, not useful "science"
1) Study period is only 2 months, what the data would show beyond that is anyone's guess. 2 months is a very short time period that tells you next to nothing.
2) First 7 days after injection is excluded...why? Once the shot goes into your arm, you should be considered vaccinated.
3) Only measures against COVID-19 hospitalizations (however that is determined) and not all-cause hospitalizations.
4) This isn't a randomized controlled trial
5) Healthy vaccinee bias not accounted for
Hi Paul. Thanks for your response. I know we don't see eye to eye on this, and I don't think that's going to change. But some responses regardless:
1. Yes, unfortunately, we are at the mercy of time. Time is a limitation out of our control.
2. It's excluded because it takes 2 weeks for the immune system to be activated. It's not "automatic" protection. This is a common misconception with vaccines.
3. Not just hospitalizations were measured, but ED and outpatient use were also tested. We cannot do all hospitalizations (in the US) because we don't have a vaccine registry like Denmark has, for example. Perhaps you can help advocate for better public health data so we can test things like this. UK has a great analysis of vaccine impact over time against all-cause death. The effect is still very clear.
4. This would be best in the ideal world but it hasn't been done as there are serious ethical reasons for doing an RCT with high-risk patients, like those over 60.
5. I think this was definitely a bias earlier in the pandemic, where people vaccinated were more likely to mask. These days, there may be small bias, but certainly not enough to explain a 70% difference.
Are we ever going to get past the conspiracy theory that claims because a pharma funds a study, that study is automatically biased pharma propaganda?
AFAIK these trials are conducted by government agencies and/or independent 3rd-party contract laboratories, insulated from manufacturer influence. Manufacturers don't want the legal exposure of defending against fraud allegations arising from putting out "biased propaganda" (even if the case ends up being dismissed after over a decade of legal expenses and bad PR, as the case against Merck for their mumps vaccine recently was - and rightly so).
Frankly. I want manufacturers to pay for all the studies done on their products. I want my tax dollars to go towards buying the products shown to work.
Thank you for the response, Katelyn.
2) 3) Yes, understood. This is why you need to run randomized controlled trials to control for as many of these confounding variables as possible. Unless the UK analysis is accounting for healthy vaccinee bias, etc, the data tells you very little. And like all data covid-related, it needs to be age-stratified. These vaccines may reduce the absolute risk of death or hospitalization for a diabetic 70 year-old, but not for a healthy 30 year-old. The VE data is reported as relative risk ratios and not absolute risk reduction. This is done for a reason. 70% VE could be 10/3 out of a million or 10/3 out of 100
4) There are also serious ethical issues with pushing shots on everyone before/without knowing anything about efficacy or safety.
5) There's never been any evidence that wearing a mask prevents hospitalization from covid.
Again, I will come back to this. The Phase III Pfizer trial for the original shot didn't show a mortality or hospitalization benefit. No RCT has for any of the shots.
In 40 years associated with medicine, I have yet to see a perfect clinical trial. This kind of critique may be well suited to invited critique in a peer reviewed journal, but it is obfuscating to a general audience. There is broad concurrence amongst experts on the big issues, like: Get vaccinated. There is far less risk of vaccination complications than complications of the infection itself. Even partial immunity has value to the individual and the population. During high viral activity times, wear a quality mask in public. Avoid high probability exposure in times of high viral activity. If you're sick, stay home. If you're sick, get tested and take the medication to reduce duration/severity of symptoms. COVID is a bitch; so is long COVID
This is not rocket science, not particularly controversial at this point. As a population, we have rapidly become complacent again; look at the low incidence of vaccination amongst high risk populations this time around. It's no harder to get a COVID vaccine than to get a flu vaccine. I got both in the same sit, in the same arm. Other than a sore arm for a couple of days, no muss, no fuss.
Very excellent summation.
"There is far less risk of vaccination complications than complications of the infection itself."
Add-on:
https://www.cdc.gov/mmwr/volumes/73/wr/mm7301a4.htm?s_cid=mm7301a4_w
Paul: I think people wouldn't take your tone as quite so hostile/troll-like if you simply dialed-down on the scare-quotes. As a New Years resolution on my end, I'll do my best to look past that pattern - but I'd like you to reciprocate by not using them.
Fully vaxed and following your guidance. I appreciate your insights.
Thank you so much for the update. I appreciate the time that you put into these. I work in healthcare and I have had multiple exposures to Covid from patients who tested later and found out they had it, and suspected Covid exposures from people who do not test and just assume that everything is "just a cold." To my knowledge, I have only had Covid once. I was wondering if Covid exposures for short periods of time act almost like a vaccine and actually keep the antibody and/or T cell response primed? I'm not suggesting that anyone should do this on purpose. I'm just genuinely curious about this.
A really good question, but exposure doesn't necessarily mean infection. We need to be infected for our immune systems, and certainly the T-cells, to be primed. I would suspect you have amazing hybrid immunity at this point, though.
Thank you so much for taking the time to answer my question. :)
God, wouldn’t that be great? I’m a high school teacher…I am probably racking up tons of those short exposures!
I'm curious about this too. It's not the exposure alone, but could frequent exposure be resulting in infections you are unaware of, where you are asymptomatic or barely symptomatic because your immune system fights it off quickly before the virus replicates too much.
I think that this is definitely a possibility. I do test when I am symptomatic, even if the symptoms are pretty mild. What is weird is I did not catch it when other family members that I live with had it and we did not isolate either. My 2 boys and my husband each had it twice and I thankfully avoided it each time. When I actually did catch it, I have no idea where it came from. It was quite the mystery. My husband says that I'm a unicorn.
I have read that answer is no, but I feel like being exposed and not becoming ill has to have some benefit.
Your last post said that people develop symptoms sooner in the infection cycle now that most of us have prior exposure via some combination of vaccination and infection. That seems consistent with this post that says viral load now peaks a few days after symptom onset, instead of around symptom onset.
So i wonder if that means that antivirals like paxlovid are useful later (as compared to the starting point of "has symptoms") than they used to be, because the real starting point has to do with viral replication. It's anyone studying alternative paxlovid dosing regimens?
I've also wondered that about rebound, and if perhaps paxlovid would be more effective if it were administered for 7 days instead of 5. (Or started later, or for fewer days ... I suspect the very first study used 5 days, was found to be effective, and wonder if anyone has looked into improving that.)
The Paxlovid dosing regimen is something that frustrates me to no end. Because, no, Pfizer doesn't seem to be testing this. And it really needs to be tested. For example, I really don't think a 5-day course is enough, given the rebounding. We really need a 10-day course. However, we don't know. I think this is where FDA should pressure companies to continue to look into the efficacy of their products, especially since Pfizer is now charging $1400 a course. Rant done.
Katelyn,
I have to respectfully disagree with the concern about "rebound" (inflammatory phase) with is the second phase of this biphasic disease. A recent study confirm that this is mild and noted in the MMWR.
"CDC examined SARS-CoV-2 rebound studies among patients who did and did not receive antiviral treatment. No consistent association between treatment and rebound was identified. The prevalence of rebound varied, depending upon host factors and the definition of rebound. Rebound symptoms were mild. No hospitalizations or deaths occurred from viral rebound." https://www.cdc.gov/mmwr/volumes/72/wr/mm7251a1.htm
I believe there are trials for 10 and 15 day courses. Will have to cite later.
You might be interested in the below link to a recent research paper which if I understand correctly says that people treated with Paxlovid experience rebound about 20% of the time: https://www.researchgate.net/publication/376727892_Persistence_of_an_infectious_form_of_SARS-CoV-2_post_protease_inhibitor_treatment_of_permissive_cells_in_vitro/fulltext/65857ea62468df72d3c74e0b/Persistence-of-an-infectious-form-of-SARS-CoV-2-post-protease-inhibitor-treatment-of-permissive-cells-in-vitro.pdf?origin=publication_detail&_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6Il9kaXJlY3QiLCJwYWdlIjoicHVibGljYXRpb25Eb3dubG9hZCIsInByZXZpb3VzUGFnZSI6InB1YmxpY2F0aW9uIn19
I wish we'd put this "Does Paxlovid increase the risk of rebound?" debate to bed. Either it's causing it, or it's failing to stop it. An effective treatment regimen should stop the disease in its tracks so *nobody* has to miserable.
Now, let's work towards tweaking the use of Paxlovid so it works for everybody!!!
Agreed. The article I linked was co-authored by Dr David Ho who was Time Magazine’s Person of the Year in 1996 for AIDS research. He’s probably the world’s best expert on viruses.
I’d trust his research more than I trust Pfizer’s.
I also think regulators are reluctant to say anything negative publicly about drugs (and vaccines) that they’ve already approved. Face saving.
A doctor I know who does research in this area recommends taking Paxlovid up to 10 days, and stopping sooner if a person has 2 negative consecutive daily tests. This will greatly reduce the risk of rebound.
I actually corresponded with Dr. Ho via email while I had Covid in October - it gave me the courage to go for a second (10 day) round of Paxlovid after I rebounded. It worked.
I love the "up to 10 days" approach you describe - that way it lined up with the 10 day isolation period.
Wow, such a cool story.
Have you heard anything about allowing a 2nd updated Covid vaccine for elderly and immunocompromised like last year?
I think this conversation is coming to the FDA in February. I will report back, but I would not be surprised if those over 65 and *severely* immunocompromised get two Covid-19 vaccines a year.
Two vaccines/year might be helpful for vulnerable populations IF the vaccines are adequately matched to currently circulating variants. I worry that significant mutations are occurring or will be occurring that outrun the pace of development and release of new vaccines. A number of epidemiologists and ID specialists are beginning to express concerns about the efficacy of the currently available vaccine against JN.1 It seems that the data sets may be too old/small to ascertain efficacy with adequate certainty.
Based on the effect of household spread that you describe - do you think it might help "smooth" the waves if household members offset their boosters from one another? Hedging is a generally accepted risk mitigation strategy, after all.
What's so special about 65? And who gets to decide what "severely" means?
Great stuff, and reassuring studies. I've shared this with my Substack peeps, thank you!
Question: Received Novavax XBB 1.5 booster in October. Is there any data on waning yet? Or the need for re-boosting? I wear an N95 indoors, but I'm in a vulnerable age group and want as much vaccine protection as possible. Thanks!
Thank you so much for the updates! This information is very helpful (and some of it is really reassuring!). I appreciate you!!!