The Scoop on Boosters

The Space Shuttle Columbia on its launch pad mounted to its external fuel tank and two solid rocket boosters in 1981. These solid rocket boosters have no connection to the boosters discussed in this post. (Photo credit: US National Archive / public domain)
The Space Shuttle Columbia on its launch pad mounted to its external fuel tank and two solid rocket boosters in 1981. These solid rocket boosters have no connection to the boosters discussed in this post. (Photo credit: US National Archive / public domain)
The Space Shuttle Columbia on its launch pad mounted to its external fuel tank and two solid rocket boosters in 1981. These solid rocket boosters have no connection to the boosters discussed in this post. (Photo credit: US National Archive / public domain)

Thursday, October 21, 2021

Now again, with a flurry of recent news about vaccination options, I present answers to questions I’m frequently asked, or wish I was.

Public health officials are talking about “boosters” and “third doses” as if they’re different things. Are they?

Those are two bits of jargon that are worth explaining. Then you too can talk like the cool kids at the Department of Health. Additional doses (or third doses in the case of two-shot vaccines) are those needed when the typical initial vaccine series never produces an adequate immune response. This is the case in immunocompromised patients who don’t mount an sufficient immune response to the first two doses of the Pfizer or Moderna vaccine, or the first dose of the J&J vaccine. Those additional doses are considered part of the initial series because they are just trying to get the immune response high enough for the first time.

On the other hand, when someone has adequate immunity from the initial vaccine series, but then over time their immunity wanes, a vaccine dose given to raise their immunity back to adequate is called a booster. So people with normal immune systems have a good response to the initial COVID vaccine, but then many months later, their immunity fades. The vaccine to address that is called a booster.

An example is the current shingles vaccine, which is a two-shot series. The second one isn’t called a booster because you need the second one for a decent immune response, it’s just part of the initial series. On the other hand, a single tetanus shot yields a great immune response but one that fades over time, so we need a booster every ten years. Get it? The distinction has nothing to do with what’s in the syringe. It’s about what the dose is being used for.

That’s a fairly pointless distinction, and a dumb way to use jargon.

Absolutely. Medical jargon is usually dumb and frequently serves no purpose. Only engineers have cool jargon like max q (the time at which a rocket experiences maximum dynamic pressure), MECO (main engine cutoff), and LEO (low earth orbit). But that has to do with rocket boosters which we’re not discussing today. But if you learn the medical jargon, you can at least follow along.

So who should have an additional dose?

The Centers for Disease Control (CDC) recommends that people with compromised immune systems who received an mRNA COVID vaccine (those are the Pfizer and Moderna vaccines) receive an additional dose of the same vaccine at least 4 weeks after their second dose.

Who counts as immunocompromised?

Patients are considered immunocompromised if they are being treated for cancer, had an organ transplant or stem cell transplant for which they are receiving immunosuppressive medicines, have a primary immunodeficiency syndrome, have advanced or untreated HIV infection, or are being treated with high dose corticosteroids or other immunosuppressive medicines. The CDC page on additional doses has the details.

What if an immunocompromised patient received the J&J vaccine?

There’s currently no recommendation for additional doses for patients who received the J&J vaccine but stand by. That is likely to change as more data is reviewed.

OK. So immunocompromised patients should have an additional vaccine dose. Who should have a booster?

Boosters are recommended for the following groups of patients if they received their most recent dose of COVID vaccine at least 6 months ago: people 65 years and older, adults who live in long-term care settings, adults who have medical conditions that would make COVID particularly dangerous, and adults who live or work in settings that place them at high risk. The details of each of these groups are at the CDC page on booster shots.

As of a few days ago, boosters were only recommended for people who have received the Pfizer vaccine. But just this week the FDA authorized boosters for those who received the Moderna and J&J vaccine as well. The CDC will likely evaluate this recommendation in the next few days at which time boosters for these patients should be available at pharmacies.

Should the booster be of the same brand as the original vaccine series?

As of a few days ago, the answer was yes. Again, this week the FDA authorized allowing patients to get a booster of a different brand than their initial vaccine. And again, the CDC will evaluate this recommendation soon. This recommendation is based on a study that showed that patients who initially received the J&J vaccine had a bigger increase in antibody levels if they received a Moderna booster than a J&J booster. There doesn’t seem to be any guidance on which brand of booster patients should get, just that they can get any brand. That will at least increase flexibility when pharmacies have only one vaccine available. And it will allow patients who developed side effects after their primary vaccine series to try a different vaccine for the booster.

Why shouldn’t everyone get a booster?

That’s a good question. Many of my young and healthy patients who don’t meet any of the high-risk criteria above have expressed interest in getting a booster. That makes sense. Israel, which vaccinated virtually their entire population (12 years and over) with the Pfizer vaccine, is recommending boosters for everyone.

But the vaccines, while extremely safe, aren’t entirely harmless. For example, temporary swelling of lymph nodes under the arm has been reported after COVID vaccines. And this happens more frequently after booster doses than after the first two doses. There’s also a very (very very) rare side effect of the vaccine of myocarditis, heart muscle inflammation, that happens mostly in young men. There have been about 24 cases of myocarditis for every million doses of vaccine given (that’s one case for every 41,000 shots), and most of these cases have resolved entirely without lasting harm. But even this very small likelihood of harm suggests that if we were to give booster doses to people who were at very low risk of harm from COVID (like very young people) we might be doing about as much harm as good.

Finally, the data on the benefit of boosters isn’t nearly as strong as the data on the safety and effectiveness of the primary vaccine series. Each of the three vaccines went through very large randomized controlled trials with tens of thousands of patients. This yielded the most reliable sort of evidence that the vaccines are safe and effective. But the data for boosters is based on observational studies which simply follow populations of patients to see which patients have breakthrough infections and use that information to infer which groups would benefit most from boosters. This sort of information is much more susceptible to confounding factors and biases.

So I don’t suggest rushing to get a booster if one isn’t recommended for you. Wait a while and watch the recommendations as we learn more.

OK. So now I get the difference between “third doses” and “boosters”. Is the actual stuff in the syringe the same thing for each?

The Pfizer booster is the same as the first two doses of the Pfizer vaccine. And the J&J booster is the same as the initial J&J dose. The Moderna booster however is half the dose of the first two Moderna shots. So if you’re getting a third Moderna dose because you’re immunosuppressed, that’s actually not the same as the Moderna booster.

Is there anyone who should avoid the booster if they’re eligible?

If you tested positive for COVID-19 or if you received monoclonal antibodies for treatment or post-exposure prevention of COVID-19 you should probably wait 90 days until receiving a booster shot.

Do you have a favorite booster?

No. But I’m very excited about the Ariane 5 rocket, which features two solid rocket boosters and is scheduled to launch the James Webb Space Telescope in December. I hope to watch the launch live and cheer when it passes max q and when it reaches MECO.

Learn more:

COVID-19 Vaccines for Moderately to Severely Immunocompromised People (CDC)
Who Is Eligible for a COVID-19 Vaccine Booster Shot? (CDC)
Evidence to Recommendation Framework: Pfizer-BioNTech COVID-19 Booster Dose (CDC)
Should I Get a Covid-19 Vaccine Booster Shot? What to Know (Wall Street Journal)
Moderna and J&J Covid-19 Boosters, Mixing and Matching Authorized by the FDA (Wall Street Journal)


Mandate Vaccines, Not Masks

Sunday, August 1, 2021

A couple of months ago I was desperately hoping that my next post about COVID-19 would be a retrospective, summarizing what we had learned and looking forward to a post-pandemic world. I am extremely ready to be done with this microscopic monster, but it is clearly not done with us.

In LA County, as well as in the US, case counts have been rapidly rising in the last few weeks. News stories warning us about the highly infectious delta variant are ubiquitous. In fact, it’s hard to find a news story in which “delta variant” is not preceded by “highly infectious”. Hospitalization rates are also climbing. Death rates are climbing nationally and will likely start climbing in LA in the next few weeks.

In the meantime, vaccination rates have slowed to a trickle. Nationwide about half the population is fully vaccinated. LA County is doing a little better, with 62% fully vaccinated. And the limiting factor on vaccination is no longer supply. Vaccines are available for the asking, free of charge, frequently with no appointment necessary. The only limitation on vaccination rate is demand.

And, if this wasn’t bad enough, stories about breakthrough cases are circulating. Breakthrough cases are COVID-19 infections in fully vaccinated people. Just when we’re trying to convince everyone that the vaccines are safe and effective, we’re hearing that the number of breakthrough cases are increasing, and that recent research shows that breakthrough cases can transmit the novel coronavirus to others. Oy vey.

So what’s a well-intended public health official to do? Los Angeles County and more recently the CDC have recommended that everyone wear masks indoors, changing a previous recommendation that only unvaccinated people need to mask inside.

The evidence for the effectiveness of face coverings in preventing COVID infectious in the community is very weak. I’m only aware of one randomized trial testing the efficacy of masking in the community (as opposed to in healthcare settings). Though the study was flawed, it showed no decrease in infections between the masked group and the control group. Nevertheless, most experts assume that masks must offer some protection, but in the absence of rigorous studies, quantifying the level of protection is difficult. Compared to vaccination the assumed level of protection from masking is much much less. Nevertheless, since these measures are independent, they should have additive benefits. So why not do both? Why not encourage vaccinated people to mask?

Keep ICU Beds Open

To answer that question, we first have to answer another broader question. What are we trying to accomplish? What is the goal of our pandemic response? Or, what should it be? Initially, when the pandemic was new, when our ICU protocols were evolving, when hospitalizations were first climbing exponentially, the goal was simply to keep from exhausting finite healthcare resources. We wanted to “flatten the curve” so that the last ICU bed, the last ventilator, the last nurse would remain available for the next patient. We did that. Even in the hardest hit areas, even with patients in New York being transferred between hospitals, no patient was turned away. There is no chance of the healthcare system being overrun this time. Half of us are vaccinated, and our inpatient protocols have improved dramatically.

Disease Eradication

Are we trying to eradicate the virus? That goal is completely unrealistic. That is impossible short of putting everyone in the world in solitary confinement for a couple of weeks. The virus will continue to circulate among humans and will join the older coronaviruses, influenza viruses, rhinoviruses that occasionally make us sick. We will no more be able to eradicate COVID than the common cold.

Minimize Bad Outcomes

Perhaps we’re trying to prevent very bad outcomes, like hospitalizations and deaths. That would be a worthwhile goal. But if that is the outcome that we focus on, we quickly realize that the current surge is almost entirely affecting the unvaccinated. Lost in the reporting of the numbers of breakthrough cases and the infectiousness of breakthrough cases is the simple fact that virtually all breakthrough cases are very very mild. The CDC tabulates breakthrough cases that have led to hospitalization or death. As of July 26, 6,587 fully vaccinated people were infected with COVID and were hospitalized or died. That’s out of 163 million fully vaccinated Americans (about half the population). When we exclude those that had asymptomatic infections and were hospitalized or died for reasons unrelated to COVID (for example someone who tests positive, has no symptoms, and then dies in a car accident) we are left with 4,641 hospitalizations and 954 deaths. That’s one death for every quarter of a million vaccinated people.

The current 7-day average of daily hospitalizations for COVID in the US is 5,475, and deaths is 305. That means more people are being admitted to US hospitals every day with COVID than all the vaccinated people that have ever been hospitalized since vaccination started. And every three days as many people die of COVID as all the vaccinated people who have died since vaccination started. That means that virtually all the hospital admissions and deaths of the current surge are among the unvaccinated. This is the simple message missing in most reporting, that we’re now experiencing two different pandemics. COVID is now a lethal plague for the unvaccinated, and usually an uncomfortable nuisance for the vaccinated.

So if we’re trying to prevent hospitalizations and deaths, we have to continue the difficult work of persuading people to get vaccinated. There is little reason to suspect that the very very few hospitalizations and deaths among the vaccinated would be significantly lowered by masking them.

Minimize Infections

Another possibility is that we’re simply trying to minimize infections for its own sake. Isn’t it worthwhile to keep the case counts low just so that fewer people are sick? Well, given that we’ve just seen that breakthrough cases in vaccinated people tend to be very mild, there are important tradeoffs to consider. How many hundreds of people should mask to prevent one person from having a cough and a runny nose for a week? Is it worthwhile mandating a weak intervention for everyone when a very effective intervention is readily available?

Which strategy might persuade an open-minded vaccine skeptic? Telling vaccinated people that they must also mask implicitly suggests that they are at risk. On the other hand, making it clear that the current surge is dangerous only for the unvaccinated emphasizes the value of the vaccine.

Prevent Future Variants

And the final, and frequently mentioned, concern of public health officials, is that the more people carry the infection, the more likely it is that more mutant variants will emerge. The fear is that a future variant will escape vaccine suppression, and we’ll be back to square one. That’s a reasonable concern, but masking Americans will not significantly decrease the global case counts. If we want to prevent the omega variant, we must help vaccinate the rest of the world. The delta variant didn’t originate in the US. Unless we cut off all international travel (please, let’s not), variant suppression has to be a global effort. That makes masks on Americans entirely irrelevant.

I’m not suggesting that individuals disobey their local mask recommendations. I now wear a mask inside. But I would like to persuade public health officials that their current course is ineffective and self-defeating. It’s ineffective because it won’t decrease severe outcomes, and self-defeating because it will decrease interest in vaccination. It is also needlessly terrifying my patients. My average 70-something-year-old patient is now uncertain that her vaccine is protecting her, when she should be confident that it is. She is emailing me to ask about boosters. (Not yet. Stay tuned.) She is wearing masks outdoors. (Stop that. There is no COVID transmission outside.) And she lives in fear of contracting COVID, when most likely it would be no worse than a severe cold. (An important exception is vaccinated people with immunosuppressive diseases or on immunosuppressive medications. They should wear masks indoors until case counts decline.)

And I’m certainly not suggesting that Departments of Health or governments mandate the vaccine. But, as soon as the FDA approves them, private employers should mandate the vaccine. Schools should mandate the vaccine. Crowded businesses who want to reassure their customers that they are safe should mandate the vaccine. That will persuade people on the fence to get the vaccine. And having more vaccinated people is the only way out of this disaster. And then I’ll be able to write a post about the pandemic in past tense.

Learn more:
CDC Urges Vaccinated People to Resume Wearing Masks Indoors in Some Areas (Wall Street Journal)
The Delta Variant and Covid-19 Vaccines: What to Know (Wall Street Journal)
COVID-19 Vaccine Breakthrough Case Investigation and Reporting (Centers for Disease Control and Prevention)
COVID Data Tracker Weekly Review (Centers for Disease Control and Prevention)
COVID-19 Home Page (LA County Dept of Public Health)
Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers (Annals of Internal Medicine)

My previous posts on the pandemic:
The Light At The End Of The Tunnel
Where Can I Get The COVID-19 Vaccine?
A New Hope
The Beginning Of The Middle
Contagion And Contrition
Our Quandary And Your Queries
Summary, Speculation, Suggestion
Think Local, Act Local
Testing, Testing Part 2
Of Masks And Meaningful Measures
Updates From The Socially Distant
Testing, Testing
Novel Coronavirus FAQ Part 2 – Pandemic Hullabaloo
Coronavirus Frequently Asked Questions
Community Transmission Of Novel Coronavirus In LA County
What You Need To Know About The Novel Coronavirus


The Light at the End of the Tunnel

7-day average of daily LA County COVID-19 cases calculated on Sundays

Wednesday, March 17, 2021

7-day average of daily LA County COVID-19 cases calculated on Sundays
7-day average of daily LA County COVID-19 cases calculated on Sundays

It’s been a long dark night
And I’ve been a waitin’ for the morning
It’s been a long hard fight
But I see a brand new day a dawning

— Dolly Parton, Light of a Clear Blue Morning

In medicine, the light at the end of the tunnel is usually the colonoscope, but this time, of course, I’m speaking metaphorically. After a year of death, sickness, loss of work, overflowing hospitals and a complete disruption in our daily life, we sense that something resembling our pre-pandemic life might be around the corner.

In LA County, COVID-19 case numbers have been steadily falling since their January peak and are now near the same level as their October nadir. Hospitalizations, deaths, and the fraction of COVID tests that are positive have also been steadily declining since January. These general trends are similar to the national data and have led some experts to predict that we’ll reach herd immunity by April.

Experts don’t know why case numbers are falling so quickly, just as it was unclear why they rose so quickly in November. The vaccination drive is likely one reason for the declining cases. Through vaccination, our most vulnerable people are quickly becoming our least vulnerable people. Over 100 million vaccine doses have been administered in the US, and the rate of vaccine delivery and administration is accelerating.

While nationally the endeavor to vaccinate the population is progressing very well, at the local level, and at the individual patient level, the process is frequently frustrating and disorganized. So bear with me for two paragraphs while I summarize who can get the vaccine in LA, and how to do it. As of this week, eligibility for the vaccine has been expanded to people with certain medical conditions that would make COVID-19 particularly dangerous. The groups that were previously eligible, people 65 and over, healthcare workers, and workers in specific essential and high-risk industries, continue to be eligible. The LA County Dept of Health Vaccination Appointments website has a complete list of the occupations and medical conditions that are now eligible. Please check it out. The same site allows you to find and schedule an appointment.

I urge everyone eligible to get vaccinated as soon as they can. Please note that a doctor’s note is not required to document the high-risk medical condition. (The reason for that is logistical. Most primary care doctors have over 2,000 patients. Some of them don’t use electronic medical records. They could not possibly generate the documentation needed for each patient rapidly enough to vaccinate all their high-risk patients.) All that is required for eligible patients is that they complete and sign a self-attestation form stating that they have a condition or disability that makes them eligible. So by all means let your doctor know after you’ve received the vaccine, but there’s no need to call her for documentation ahead of time.

So cases are declining, vaccine eligibility has broadened, and vaccinations are accelerating. It sounds like smooth sailing until we reach herd immunity. What could be bad? Well, there are three storm clouds threatening to ruin our voyage: virus variants, vaccine hesitancy, and terrible public health messaging about life after vaccination. Let’s examine each one.

New mutant variants of the COVID-19 virus have been identified that are more infectious than the original virus. The variant first identified in the UK is rapidly spreading across Europe causing widespread lockdowns and overwhelming healthcare systems. So far, these variants don’t seem to be causing more severe disease, and so far, the vaccines used in the US seem to be effective against known variants. The rapid spread of these variants in Europe and their increasing prevalence in the US has led epidemiologists like Michael Osterholm to warn of a possible surge in cases in the US in the next several weeks. So while some experts are predicting that by April enough people will be vaccinated that COVID will dwindle away due to herd immunity, others are predicting that by April a tsunami of variant cases will wash over the US. Time will tell. If a surge of cases is coming, vaccination efforts in the next few weeks will be critical. Each vaccine dose is a sandbag set against the coming wave.

That brings us to the problem of vaccine hesitancy. A significant but fortunately shrinking number of Americans are worried about receiving a COVID-19 vaccine. This is despite the ample and growing evidence of the efficacy and safety of the three available US vaccines. With over 10 million doses delivered, even very rare harms would have been detected. If one of the vaccines caused a serious side effect even 1% of the time, that side effect would have been seen in tens of thousands of people by now. Similarly, if the vaccines were ineffective, thousands of vaccinated people would have already contracted COVID. They have not. If you’re uncertain about getting the vaccine, please read this article debunking the most prevalent vaccine myths. If you’re my patient, please call me. I’d love the opportunity to hear your concerns and to try to address them.

And an important aside: Please accept whichever vaccine is offered to you first. The differences between the vaccines in preventing serious illness, hospitalization and death are very small. They’re all very effective. And they’re all very safe. But if a surge in cases is coming, the difference between getting a vaccine now or waiting a few weeks might be huge.

And the final storm cloud threatening our future is the terrible public health messaging in the US about life after vaccination. Initially, the Center for Disease Control and Prevention’s (CDC) recommendations for vaccinated people were identical to those who were not vaccinated: masking in public, social distancing, avoiding gathering with those from other households. This was in sharp contrast to the messaging in Israel which essentially stated that the vaccine was the path to return to a normal life. Since then, the CDC has relaxed their restrictions somewhat. Fully vaccinated people can gather indoors with other vaccinated people without masking, can gather with unvaccinated people from one other household, and need not quarantine after exposure to someone with COVID. But at all other times we should still mask and physically distance from others.

Given the proven effectiveness of the vaccines, why are these restrictions in place? The CDC is concerned about two issues. One is the possibility that vaccinated people could have asymptomatic COVID infections and then infect others. The second is that we’re not sure how long protection from the vaccines will last. Note that asymptomatic transmission is a theoretical concern, not a documented problem. In the millions of vaccinated people, we haven’t seen a flurry of unvaccinated people getting COVID from asymptomatic vaccinated people. And of course we don’t know how long vaccine immunity lasts. The pandemic has only been here for a year. The only way we’ll find that out is when vaccinated people get infected in meaningful numbers as their immunity wanes. So in the absence of data the CDC has chosen to err on the side of caution and maintain restrictions, which I believe is exactly the wrong approach. It would have been much better to lift all restrictions with a warning that if asymptomatic transmission or waning immunity come about, restrictions might be reimposed.

If I was a public health official (and this post should make it obvious why I’m not) my message to vaccinated people would be the following.

We might have to change all of this in the next weeks or months if we find out a lot of you are infecting unvaccinated people, but for now, lose the masks, go to restaurants and bars, and greet long-lost friends by licking their eyeballs and putting your pinkies in their nostrils (after getting their permission; otherwise it’s battery). Forget about COVID-19. You are very unlikely to get it, and you are very unlikely to transmit it. You can wear a mask if you want, but even Michael Osterholm says that a vaccinated person wearing a mask has 99% of their protection from the vaccine and 1% from the mask. So the mask isn’t adding much. Go forth and live your life.

This would be every bit as consistent with the available data as the current CDC recommendations, but would have the huge advantage of making the vaccine much more attractive to those who are hesitant. And it would support the notion that public health officials are our servants, not our nannies.

Don’t get me wrong, I still follow the current recommendations. (And you should too.) I’m fully vaccinated, yet when I walk to work I wear a mask so that my sunglasses fog up and I walk into lampposts. And, of course, I wear a mask in the office (as do the other doctors and staff who are all also fully vaccinated). But this is now simply good etiquette and theater, not science.

And some good etiquette and theater is necessary. Many people are scared. They are frightened to see unmasked people on the sidewalk and would be shocked to see a doctor working without a mask. I’m not advocating scaring or shocking anyone. I’m just suggesting that with better public health messaging those who are scared could be educated and reassured. But our current messaging simply encourages more fear.

For a year, our kids’ education has been derailed, our parents have been isolated, our friends have been absent, our vacations have been cancelled, our dreams have been put on hold. The vaccines are our ticket to start chasing our dreams again, but first we’ll have to stop running away from our fears.

All at once the clouds are parted
Light streams down in bright unbroken beams
Follow men’s eyes as they look to the skies
The shifting shafts of shining weave the fabric of their dreams

— Rush, Jacob’s Ladder

Learn more:
LA County Daily COVID-19 Data (LA County Dept of Public Health)
We’ll Have Herd Immunity by April (Wall Street Journal, opinion)
COVID-19 Vaccination Appointments (LA County Dept of Public Health)
COVID-19 VACCINE ELIGIBILITY: Self-Attestation (LA County Dept of Public Health)
Europe staggers as infectious variants power virus surge (Associated Press)
U.K. Covid-19 Strain Might Account for 25% to 30% of U.S. Cases (Wall Street Journal)
The Osterholm Update: COVID-19 Podcast (Center for Infectious Disease Research and Policy)
Americans are increasingly willing to get vaccinated, according to a new survey (New York Times)
6 myths about the COVID-19 Vaccines — debunked (Association of American Medical Colleges)
When You’ve Been Fully Vaccinated (Centers for Disease Control and Prevention)