The information below is based on what is known as of writing this post on December 15, 2020. References to trials unless otherwise specified are to the Pfizer vaccine which has been granted Emergency Use Authorization by the FDA.
Q: Does the Pfizer vaccine prevent you from getting COVID-19?
A: This may come as a surprise, but we do not know.
To further elaborate, we need to discuss Infection vs. Disease. Infection simply refers to contracting the virus. Disease refers to developing symptoms from the virus. The first important note from the Pfizer trial is that it did not look at infection, but rather, disease. Put in other words, it did not look at whether the vaccine prevents you from contracting COVID-19, but whether you would get sick from COVID-19.
What about the famous the 95% efficacy rate quoted? That refers to 95% efficacy against disease (i.e. did people become symptomatic from COVID-19), not infection. The trial showed that the vaccinated group had a reduced the risk of developing disease from COVID-19 by 95% when compared to the placebo group. Which is fantastic results.
If you are interested in the raw numbers, 8 out of 18,198 participants who received the vaccine went on to develop disease from COVID-19 (0.04%), whereas 162 out of 18,325 in the placebo group developed disease (0.88%). (Of note, “efficacy” is a term used in an ideal clinical trial scenario whereas “effectiveness” is what plays out in the real world. There tends to be a slight drop, but the vaccine is still expected to be very effective at preventing illness from COVID-19, even if a little less than 95%.)
Q: Does the vaccine prevent transmission of the virus?
A: This again may come as a surprise, but we also do not know.
The trial did not look at transmission. And if the vaccine does not prevent you from contracting the virus, it stands to reason that if you were to get the virus, you would still be infectious and can spread it. We do know that the vaccine is effective at preventing illness from COVID-19. But that gives rise to a possibility of increasing the number of asymptomatic carriers as the vaccinated population increases. This can of course, paradoxically further drive asymptomatic spread, which at current estimates is already about 40-50%. That is a huge concern. Which brings us to the next question…
Q: So if I get vaccinated, can I stop wearing masks and social distancing?
A: The unfortunate answer is no. At least not yet.
The above two points – not knowing whether the vaccine prevents infection or transmission – has significant implications. Namely, vaccinated individuals would need to continue to wear masks and social distance to avoid further spread to populations with whom the vaccine has not yet reached or is not effective for.
Take for example our African American brothers and sisters. This year has been somewhat of a national reckoning on race relations, and has also highlighted racial disparities. We have seen COVID-19 affect the African American community disproportionately. Yet, they are also understandably less trusting of the medical community and particularly vaccines. A vaccine itself isn’t a solution if vaccination doesn’t occur. What is concerning is ending up with a situation where certain populations are not vaccinated while also being at higher risk for severe illness from the disease. If the vaccinated population lets their guards down and stops taking precautions, this can lead to further exasperation of an already vulnerable population’s disease outcomes. Again, this is more of a concern if the vaccine does not prevent transmission, which is still unanswered.
Bottom line, vaccines will not be the golden bullet that you wanted to get back to normal life, at least not in the next 8-12 months until enough people get vaccinated or we confirm that it stops transmission. In the meantime, think of the vaccine as a supplement to masking and social distancing, as much as it hurts to say.
Q: How long does immunity last?
A: We simply don’t know. At least four months for now. I pray much longer. Time will tell. There is a possibility of needing a booster every X months or years. We just have to wait and see.
Q: What are the risks in receiving the vaccine?
A: This is a loaded question and requires a little more than just a list of side effects. It is rightfully the source of hesitancy about receiving the vaccine. However, I believe it should not be posed in a vacuum, but rather framed as “What are the risks in receiving the vaccine versus not receiving the vaccine?”
Let’s address issues surrounding the vaccine first. Vaccines inherently do have risks of adverse events, some common and some not so common. It also must be acknowledged that this method of using an mRNA-based vaccine is new (although it has been researched for years), and therefore, there may be things discovered in a few years that were not anticipated. Further, the virus itself causes systemic (i.e. widespread in the body, not just isolated to one organ) illness, the exact mechanism of which is still not fully understood. And if the virus itself is not well understood, what then can be said about the effects of a vaccine meant to combat it?
We have good data on the common side effects and understandably not so good data on the rare side effects. Regarding the latter, say there is a relatively rare side effect that occurs in 1 in 100,000 people. The trial enlisted just shy of 44,000 participants, of which half received the vaccine and half received placebo. It is possible that this rare side effect may have been observed in the approximately 22,000 people who received the vaccine. But it is also possible that it has not. It is only one event we are looking for and it simply may not have happened yet.
Another issue is time. Researchers have two to four months of observational data from the participants in the trial (depending when they enrolled and received the vaccine). While it is true that most side effects occur within six weeks of receiving a vaccine, we do not know about the rare long-term effects. Similarly, we do not know what the body would do when encountering the virus multiple times (which is a definite possibility in the midst of a raging pandemic). For example, will it mount a hyper-immune response that can end up being detrimental? Time will tell.
There is also less data available on minorities, as 81.9% of the trial participants were Caucasian. It would have been helpful to see a more diverse trial population to flush out potential adverse events not otherwise seen based on genetic composition of different races.
As for the common side effects, they are similar to what is caused by the flu vaccine: local injection site reactions (84.1%), fatigue (62%), headache (55.1%), muscle pain (38.3%), chills (31.9%), joint pain (23.6%), and fever (14.2%). Reassuringly, date from Moderna’s trial of just over 30,000 participants (which also uses mRNA-based technology) has shown strikingly similar results in terms of efficacy, side effects, and lack of serious adverse outcomes.
As alluded to earlier, the risks of the vaccine is only half the equation that one must consider. The other half is the risk of not getting the vaccine. Over 16 million people in America have had confirmed infection of COVID-19, and the number actually infected is likely significantly higher. As of this writing, COVID-19 is taking the life of someone in this country approximately every 30 seconds. For the survivors, while many recover fully, others – including those with no or very mild symptoms – are left to live the remainder of their lives with long term damage to their blood vessels, lungs, heart, brain, and other vital organs. We are still discovering the true extent of what damage this virus causes, with the unfortunate reality that more detrimental ramifications are still left to be uncovered.
Having said that, we have a vaccine that has been shown to be 95% effective in reducing one’s chance of developing disease from COVID-19. While there may be some risks with the vaccine, there certainly are tremendous, potential deadly, risks of not getting the vaccine and contracting COVID-19.
It is worth noting that healthcare workers are being prioritized to receive the vaccine first, but it has not been mandated upon us. The vast overwhelming majority of physicians are voluntarily taking the vaccine as soon as it is made available to them (administration will be starting this week). For the general public, this prioritization serves as additional time to gather data about any potential adverse outcomes prior to the vaccine being made available to them.
Further, there will be continuous, ongoing data collection after the vaccine rollout. Existing mechanisms for reporting adverse outcomes from vaccines remain in place such as the Vaccine Adverse Event Reporting System (VAERS, www.VAERS.hhs.gov). The CDC is introducing further measures including a program called V-Safe in which every vaccine recipient will receive a text message daily for the first week with a survey link to submit any symptoms experienced, and weekly thereafter for six weeks. If a medically significant adverse event occurs (predefined to include numerous conditions including autoimmune disease, seizures, bleeding disorders, Guillain-Barre syndrome, and many others), telephone follow-up and staff-entered input into the VAERS database. This database will have continuous rapid cycle analysis being performed to evaluate for safety concerns. The vaccine can always be withdrawn if the need were to arise.
Q: Should we be concerned at how quickly this vaccine was produced and released?
A: There were some key differences in the process of developing a vaccine for COVID-19 compared to the standard operating procedure of developing vaccines. For one, federal regulators were involved from the beginning in designing the trial; as opposed to having a company such as Pfizer develop the trial, then propose it to regulators, only to be sent back to the drawing board to adjust certain things. This saves significantly on time.
Secondly, a major factor in the length of time it takes to develop a vaccine is limited resources. In the case of COVID-19, there was massive investment in these trials, on the scale of billions of dollars. Imagine trying to run a trial with a budget of $10,000 versus $1 billion, or a team of 10 people working on developing a vaccine versus a team of 10,000 people. So much more can be accomplished and expedited with a larger budget, from research, manpower, recruiting participants, and so on.
Thirdly, we are in the middle of a global pandemic that has brought world economies to their knees. There are no weekends, holidays, or days off in a pandemic. Researchers have been working around the clock.
Another factor working in favor of vaccine development is presence of the disease itself. If researchers were working on a vaccine to combat a disease that is rare, it would take exponentially longer to meet the requirements to produce statistically significant data. However, in this case, the virus is so endemic and widespread, that is not a problem. Typically phase III trials have about 10,000 participants. In the case of COVID-19 vaccines, trials have recruited over 30,000 participants. Pfizer’s trial had just shy of 44,000 participants.
The primary concern of some experts is the length of observation for adverse events of participants in the trial, which stands currently at two to four months. However, in the midst of a global pandemic with current global loss of life from confirmed COVID-19 occurring at least once every eight seconds, at some point, a line must be drawn somewhere. Knowing that most adverse events occur within six weeks, the data available at this point is, while cannot be considered conclusive, is reassuring. Ongoing surveillance and monitoring however must continue and measures are in place to do just that as mentioned in the previous question.
Before moving on, it bears mentioning, there is a legitimate concern among many whether the decision to grant Emergency Use Authorization to the vaccine was due to political pressure. While I certainly cannot speak to the motives of any expert, it is reassuring that an independent, external committee, composed of top scientists across the country with no conflict of interest, voted to approve its use.
Q: Does the vaccine change your DNA?
A: If you forwarded WhatsApp messages saying that it does, ask God for forgiveness and stop lol. The answer is NO! It is an mRNA vaccine, not a DNA vaccine (nor a live virus vaccine, meaning you are not being injected with a part of the virus).
Let’s quickly have a short discussion on Messenger RNA (mRNA). In normal cellular function, mRNA is released from the nucleus into the cytoplasm where it goes the cell’s protein manufacturing plants (otherwise known as Ribosomes) to produce proteins. Think of it as an instruction booklet for what the ribosome is to produce. Now, mRNA is a very labile molecule that gets broken down fairly quickly. That’s part of the reason why the vaccine needs to be stored at such cool temperatures. To successfully get into the cell, scientists put the mRNA inside a lipid capsule (acting like a force shield) that allows it to be taken up into the cell when it makes contact with the cell surface. Once in the cell, the mRNA goes into the ribosome and which then follows the instructions to produce the proteins that will be excreted from the cell.
mRNA has no ability to go back into the nucleus, where DNA lives. Therefore, mRNA has no access to the DNA. Think of the nucleus as a fortified castle. So fortified in fact that if molecular scientists want to access DNA within the nucleus, they need to administer electric shocks to the cell in a process called electroporation to allow the nucleus wall to be permeable enough to be accessed. So yeah, a very labile molecule like mRNA has no chance to get in there. Basically, the vaccine has as good of a chance of turning you into Spiderman as it does of changing your DNA.
Q: Ok, if the vaccine doesn’t change our DNA, how does it work?
A: Our immune system learns by exposure. In the case of the vaccine, once the mRNA gets into the cell, it goes into the ribosome and uses the cell’s own mechanism to construct proteins that will be excreted from the cell. These proteins being created are identical to the Coronavirus Spike protein that is released had it been infected by COVID-19. The body recognizes it as the virus without it actually being the virus and mounts an immune response to it. Once exposed to the real virus, the body will be ready to fight it off.
Q: How long does it take for the vaccine to be effective?
A: As mentioned above, our immune system learns by exposure. Sometimes, the body needs multiple exposures to mount an adequate response. In the case of this vaccine, researchers found that after one dose, the efficacy was approximately 52%. Benefit is seen about 14 days after receiving the first dose (the body does take some time to mount an antibody response). However, after receiving the second dose 21 days after the first, efficacy went up to 95% seven days after that (i.e. 28 days after receiving the first dose).
In other words, if you receive the vaccine as scheduled, one dose on day 1, and one dose on day 21, by day 28, you would be significantly protected from developing disease from COVID-19.
Q: Does the vaccine contain aborted fetal tissue?
No. There is no component of fetal products within this vaccine. Zero. None. Not a trace. Not even 0.001%. Nothing. No amount of citing random WhatsApp messages, unrelated vaccines, or your random doctor uncle changes that fact.