11. I'll take another shot.
Everyone needs a boost.
While the worry of the omicron variant of Covid is still unknown, booster shots for different vaccines are on the rise. With relatively slow global vaccination, and persisting Covid infections in all corners, this was probably inevitable.
Booster shots, for the most part, are either full or partial doses of the original vaccine you received. They are usually the same dose and medicine you received previously, and act to recharge your immune system to ward off an attack. Mix-and-match of different vaccines is perfectly fine.
Vaccines can’t prevent an infection, but they do greatly reduce the severity of the infection you might get. Yes, you can become quite sick, even if you’re vaccinated. And yes, you can almost surely pass this infection to other people. But vaccinated individuals are much much less likely to become severely ill, and it’s probably a lot harder to pass the virus to others, though we don’t know too much about this yet.
How do Vaccines Work Anyways?
Vaccines trick your body into thinking it has an infection, spurring to action our natural immune system to assemble a response. There are two main types of vaccines1 in the US, and both work to coerce your body to react. mRNA vaccines (Pfizer and Moderna) contain tiny lipid (fat) droplets seeded with incomplete bits of genetic code that fool your body to produce tiny protein fragments that resemble the virus, which then causes your immune system to ramp up a response. Viral vector vaccines (Johnson & Johnson Janssen) are harmless shells of viruses that have been modified to have chemical structures and features of Covid, but they lack the ability to reproduce once they enter the body.
In both cases, they entice your immune system to ward off this apparent infection by spurring to action an army of different cells that work in tandem to
Remember what the virus looks like,
Make antibodies which help identify and flag future infections, and
Kill any future invading viruses.
My immunologist friends would certainly roll their eyes at this very simple explanation, but good enough for now.
The problem are with those cells that are meant to remember what the virus looks like - they eventually forget. And the antibodies that are meant to flag infections for those virus-killing cells? They can eventually disappear, too. Over time, this leaves us unprotected and vulnerable to another infection.
And this is true whether you received a full vaccine, or survived an infection. And while those who had Covid do have some immunity, it seems to be not a strong as if you were given immunity by a vaccine.
Though it seems a little ironic, vaccines just seem to work better in protecting people than the actual virus.
Boosters and Health Equity
There are many people concerned with the deeply inequitable distribution of vaccines across the world, with most developed nations having ready access to different vaccines, and many developing nations lacking almost any access.
This poses strong moral equity questions about accepting a booster, with a belief that accepting a booster is withholding a lifesaving treatment from someone else in the world who hasn’t yet had a single dose.
But that probably isn’t true, and here’s why: abstaining from a booster dose is unlikely to improve supplies elsewhere because vaccine procurement is a national or international effort. The flow of vaccines from manufacturer to someone’s muscle is complicated, and involves international logistics, giant purchase orders, customs brokers, huge cargo planes, and lots of boxes of syringes. Not to mention the tens of thousands of people - from warehouse workers to public health data trackers to nurses who are needed to make these important deliveries.
Because of this complex challenge, efforts to distribute vaccines globally - both first and second doses, and booster doses - have been mixed at best. There are still far too many nations where vaccines are simply unavailable to the public.
Distributing vaccines globally is an extremely complicated puzzle, and the bottleneck is not the physical availability of doses - it’s legal agreements, byzantine logistics, and staffing limitations that slows these doses into different countries, and then into the upper arms of billions of people who still need it.
Even if you’re lucky enough to live in a location where vaccines are plentiful, abstaining from a vaccine probably will have little meaningful impact for vaccine availability in locations where there are these clear inequities. The barriers to delivering vaccines to other nations remains extremely high. And abstaining from a vaccine only increases the risk for you, and those around you.
Boosters Now (and probably next year, too)
It’s pretty clear that immunity to Covid is starting to decline about six months after a vaccine sequence, and this isn’t really all that surprising. The same thing happens with the other vaccines you probably have had in the past -Measles Mumps & Rubella (MMR), Polio, Diphtheria, and so on. You might be surprised to learn that your immunity to these other diseases has probably also waned over the years.
But here’s the big difference. For measles, there have been between 55 and 1200 cases of measles each year across the entire the United States over the last 10 years. That is a national annual rate of somewhere in the vicinity of 0.016 to 0.36 cases of measles per 100,000 people in the US.
Compare that with the growing and ominous incidence rates of Covid where you live. In my community, a highly vaccinated community, it’s around 50 cases per 100,000 people.
It’s useful to dig in to the Covid numbers a little more by comparing it to Measles.
Let’s assume Measles is at its worst (which, was in 2019, driven by local outbreaks on the West Coast of the US and in New York), where annual Measles was 0.36 cases per 100,000 population. This is the worst is gets in the US.
Now let’s look at Covid. There have been about 49M cases of Covid in the US to date, roughly half in 2020, and half in 2021. This is a an annual rate of about 14,500 cases per 100,000 population. This tells us Covid is about 400,000 times more common than the worst Measles events.
And it is why everyone now must, and should, go out and get a booster shot.
The point is that vaccines give your immune system a needed recharge. While this might not be necessary for exceedingly rare diseases, Covid is not exceedingly rare whatsoever. In fact, it continues to be extremely common, an unfortunate but predictable byproduct of a fractured nation who abstained from being vaccinated, or for regions that made it difficult to obtain testing. These acts allowed Covid to fester, and to lurk in our communities, and it is now roaring back to life.
Even for those who are vaccinated.
The Long Game
There is growing concern by people who ask why we have to endure yet another round of shots, and this worry makes some sense. One might think ‘I did my part, why do I have to do this again?" The problem is that many people still believe that vaccines give you life-long ‘immunity’, and this is simply not true. The immune system does not work that way. It is always in a state of slow decline, and we need booster doses to keep our immune systems functioning. To remember and to react.
And again, vaccines don’t prevent infection, they just reduce the severity of disease. They also likely lower transmission rates, so we have to keep doing this until Covid eventually becomes a rarity. But we have a very long way to go.
Until most are vaccinated - both in the US and across the globe - it’s a safe bet that CDC and WHO annual flu shot guidance each summer might look a little different into the future.
Sorry kids. It’ll be double shots for all.
There are other types of vaccines too, such as protein sub-unit vaccines, but they aren’t yet widely available or used for Covid.