Over the past year, as the COVID-19 vaccine rollout ramped up, I quickly realized a few of my friends and I had conflicting opinions about vaccination. However, it wasn’t until late November of last year when the vaccine became a reality that I realized how common vaccine hesitancy was. Coincidentally, this was the same time I learnt about my friends being “anti-vaxxers” — which is short for “anti-vaccination,” or people who oppose vaccination. Although I initially thought they were joking, and was shocked after realizing they weren’t, I genuinely wanted to hear some of my friends’ concerns about vaccination and why they opted out of it. In this letter, I address the three most common concerns my anti-vax friends had.
Concern #1: “The vaccine was created and distributed so quickly; there is little research into the vaccine’s long-term side effects and efficacy.”
Considering that, before the COVID-19 vaccine, the development of the fastest vaccine took four years, it is natural for some people to be apprehensive and doubtful about the efficacy of the COVID-19 vaccine. But it is important to consider that researchers have been investigating viruses similar to SARS-CoV-2 — the virus causing COVID-19 — for many years. Viruses, just like other organisms, are grouped into families based on similar characteristics. For example, SARS-CoV-2 belongs to the coronavirus family — a family containing hundreds of other viruses, including the SARS-CoV-1 that caused an outbreak dating back to 2002, affecting 29 countries and causing 774 deaths worldwide. Dr. Eric Yager, a microbiologist at Albany College of Pharmacy and Health Sciences, has stated that research on coronaviruses has been going on for the past 50 years. This means that researchers already had some pre-existing knowledge about the diseases and hosts of coronaviruses and extensive knowledge about their genetics, even prior to the COVID-19 pandemic.

Timeline showing research on coronaviruses, which dates back all the way to the 1960s. (Image Source: Weiss, 2020)
Combined with this pre-existing knowledge, the COVID-19 pandemic rapidly accelerated research into SARS-CoV-2 around the globe. Just a few days after the first reported case of COVID-19 in Wuhan, China, researchers had already sequenced and uploaded the complete genome — all the genetic information that makes up an organism — of SARS-CoV-2. This process would have taken months to complete several years ago, but techniques are faster and more efficient today due to improved genome sequencing technology. Both the improved technology in research labs and international cooperation meant that researching the vaccine and the virus could be fast-tracked. These factors have collectively made possible the development of an efficacious vaccine in less than a year.

New DNA sequencing technology has allowed researchers to sequence genomes faster than ever before. (Image Source: Illumina)
Concern #2: “Several health risks are associated with vaccines, such as complications during pregnancy, blood clotting associated with the AstraZeneca vaccine, and autism.”
I will individually address each health risk that anti-vax people have concerns about. First, the risk of severe illness or death in pregnant individuals who have contracted COVID-19 is higher than that of non-pregnant individuals who have contracted COVID-19. In other words, the health risks from COVID-19 are significantly higher than the health risks from the vaccine because susceptibility to COVID-19 increases during pregnancy. In addition, there has been little evidence to suggest any pregnancy complications associated with the vaccine. While it may be true that the COVID-19 vaccine trials did not include pregnant participants in their research samples, we still have data available through other studies and animal testing. In animal testing, mRNA vaccines such as Pfizer and Moderna did not result in any fertility or pregnancy defects, and the same was the case with the Johnson & Johnson vaccine. Additionally, the Center for Disease Control and Prevention (CDC) is currently tracking approximately 30,000 pregnant individuals who have gotten the vaccine, and so far, there have been no further complications that affect only pregnant individuals. No fertility, pregnancy, or birth-related problems such as miscarriages, stillbirths, or preterm births have been reported after vaccination.

Risk of blood clots associated with the AstraZeneca vaccine, birth control pills, smoking, and COVID-19 infection. (Image Source: Dr. Maria Leonor Ramos)
Regarding the blood clotting associated with the AstraZeneca vaccine, there have indeed been such cases. This blood clot, termed thrombosis, is a dangerous side effect associated with the AstraZeneca vaccine. But the occurrence of such a side effect is very rare, estimated to affect about 4–6 in every one million people. I won’t deny that this is an actual health risk associated with the AstraZeneca vaccine, but there is an important point to be made here. The risk of thrombosis is very, VERY low (0.0004–0.0006%); this, compared with the risk of thrombosis from COVID-19 infections (16.5%), clearly shows that the pros outweigh the cons. Nonetheless, due to these concerns, the distribution of the AstraZeneca vaccine was severely limited, showing that the government reacted quickly when a health problem related to a vaccine arose.
Lastly, there is no link between autism and vaccination. This is a myth perpetuated by a 1997 study in The Lancet, a very prestigious journal. The study has since been retracted due to many issues, including errors in the methods, ethical violations, and conflicts of interest. The lead investigator and author of the publication, Andrew Wakefield, lost his medical license as a result of this paper. Since then, numerous studies investigating vaccination have shown no correlation with autism.
Concern #3: “Why should I trust a vaccine that isn’t even FDA-approved?”
First and foremost, the Food and Drug Administration (FDA) is a U.S. federal agency, and all my anti-vax friends are Canadians, so this should not be a matter of concern. Still, the lack of FDA approval should not even be worrying in the United States. Even if the FDA hasn’t “approved” the vaccine, it in no way undermines the fact that the vaccines have undergone robust and rigorous testing and are efficacious.
Notably, the FDA has granted the COVID-19 vaccines Emergency Use Authorization (EUA). The FDA uses an EUA to accelerate vaccine distribution during a public health emergency. This EUA utilizes the precautionary principle, which allows treatments to be accelerated. It also allows the FDA to quickly revoke their authorization (which is not the case if the FDA approves a treatment) if the need arises. Such was the case with hydroxychloroquine, which was declared a possible treatment for COVID-19 early in 2020 but FDA approval was later revoked as it showed little efficacy. Furthermore, just recently, the FDA fully “approved” the Pfizer-BioNTech vaccine. In a matter of time, other vaccines could also get the approval stamp.
And if someone is not impressed by clinical trials, research and FDA authorization, they can clearly see the positive impact vaccination has had by examining COVID-19 cases in recent months. For example, in April 2021, daily infected cases in Canada included 8000-9000 affected individuals. However, now that ~70% of Canadians have received at least one dose and ~64% Canadians are fully vaccinated, daily infected cases range from 1000-2000, where unvaccinated individuals account for the majority (~95%) of infected cases.

COVID-19 cases in Canada. (Image Source: Google)