Where we are now, how we got here, and what’s next.
In late 2019, a cluster of unexplained pneumonia cases in Wuhan, China was causing concern in the medical world. At first, many of us were uncertain how seriously we should be taking this. Sensationalism is a common theme in the media, and it could have been that it was going to be nothing. What was ahead was much more ominous than we could have ever imagined. Over the next few days, chilling images from the Eastern Hemisphere revealed how bad things were about to get globally.
COVID-19 was declared a pandemic by the World Health Organization in March and hit Belize on March 23rd. 1,2 This set up one of the worst years many of us had to live through and the race for a vaccine was on. Social distancing, mask-wearing and handwashing were our best bet to survive until then. After an insufferable, isolated and anxious year, we’ve gotten to this point. A COVID-19 vaccine was developed in record time. Two companies are leading the charge: Pfizer in partnership with BioNTech and Moderna. These are the two vaccines we will be discussing here.
Despite this being obvious good news, there are many skeptics. This isn’t a bad thing, it’s always a good idea to educate yourself and be skeptical as long as it’s for the right reason. Vaccine hesitancy presents a major obstacle to achieving vaccination coverage that is broad enough to result in herd immunity and slow community transmission. In general, vaccine hesitancy has become more common worldwide and was cited by the WHO as a top 10 global health threat in 2019.3 So, let’s answer some questions in this article and even discuss what we don’t know.
How was this vaccine developed? Was it properly tested?
Yes, it was rigorously tested. For example, in phase III, over 35,000 patients were enrolled in Pfizer’s trial.
We actually learned a lot from SARS-CoV-1 (commonly referred to as just SARS at the time) and Middle East respiratory syndrome coronavirus (MERS-CoV). Vaccine development for SARS-CoV-1 and MERS-CoV helped pave the way for rapid development of SARS-CoV-2 vaccines. Pre-clinical studies were completed with SARS-CoV-1 vaccines, and two vaccines were evaluated in small human trials; however, further work was halted once the virus was eliminated. 4,5 When COVID-19 came around, we knew a lot about coronaviruses and their Spike Protein (the target of Pfizer-BioNTech and Moderna’s vaccines today).
Before a vaccine is approved it must pass the first three phases of clinical trials. Both Moderna and Pfizer-BioNTech’s vaccine have passed Phase III. Below is a table that details each phase. Both vaccines are now officially cleared for emergency use to prevent COVID-19 in the United States.6,7
Is the vaccine effective?
Pfizer-BioNTech is 95% effective in patients over the age of 16. It is 94.7% effective in patients over the age of 65.
Moderna is 94% effective in patient over the age of 18. It is 86.4% effective in patients over the age of 65.
What’s unique about this vaccine?
Not all vaccines work in the same way. There is some impressive science in both these vaccines. In a nutshell, they induce the production of the Spike Protein by our cells which trains our immune system to recognize the threat in the future. This is a new era in medicine and the future is exciting. If you would like a more in-depth understanding of the science behind the vaccines, Dr. Habet is easily reachable at email@example.com.
How is it administered?
Pfizer-BioNTech: two intramuscular injections, 3 weeks apart.
Moderna: two intramuscular injections, 28 days apart.
Who should take it?
At-risk patients receive priority.
The most vulnerable patients are a priority. This includes:
- The elderly
- Healthcare workers and first responders
- Immunocompromised patients
- People of all ages with comorbid and underlying conditions that put them at significantly higher risk
After we have protected those most vulnerable, the rest of the population is next in line.
Moderna’s vaccine is approved for patients over 18 years of age.
Pfizer-BioNTech is approved for patient over 16 years of age
Should children or pregnant women receive this vaccine?
No safety information is available for these groups of patients. This information is still being gathered.
What are the potential side effects of receiving the vaccine?
Side effects are summarized in Table 2:
It is worth noting that patients with a history of anaphylaxis should exercise caution when receiving the vaccine. This is an extremely rare reaction and if you have no history of it, the chances of anaphylaxis are less likely than being struck by lightning.
Questions we don’t know the answers to yet (accurate to December 20, 2020):
How long does immunity last after vaccination?
Will a booster dose be necessary? If so, when?
How will patient populations not assessed in the clinical trials (pregnant women, immunocompromised patient, children, etc.) respond to the vaccine?
Will the vaccine sufficiently prevent community transmission through herd immunity?
These questions will all be answered with time and close monitoring is being conducted. At last there is some hope, there is a light at the end of the tunnel! In the meantime, please continue to socially distance, wash your hands and be mindful that your actions can save someone’s life. You absolutely are playing a vital role by protecting yourself and others.
1. Containing SARS-CoV-2 in Belize – Caribbean Medical Journal. Accessed December 19, 2020. http://www.caribbeanmedicaljournal.org/2020/06/23/containing-sars-cov-2-in-belize/
2. Cucinotta D, Vanelli M. WHO Declares COVID-19 a Pandemic. Acta Bio-Medica Atenei Parm. 2020;91(1):157-160. doi:10.23750/abm.v91i1.9397
3. Ten health issues WHO will tackle this year. Accessed December 19, 2020. https://www.who.int/news-room/spotlight/ten-threats-to-global-health-in-2019
4. Martin JE, Louder MK, Holman LA, et al. A SARS DNA vaccine induces neutralizing antibody and cellular immune responses in healthy adults in a Phase I clinical trial. Vaccine. 2008;26(50):6338-6343. doi:10.1016/j.vaccine.2008.09.026
5. Lin J-T, Zhang J-S, Su N, et al. Safety and immunogenicity from a phase I trial of inactivated severe acute respiratory syndrome coronavirus vaccine. Antivir Ther. 2007;12(7):1107-1113.
6. Emergency Use Authorization (EUA) | Moderna COVID-19 Vaccine. https://www.modernatx.com/covid19vaccine-eua/. Accessed December 19, 2020. https://www.modernatx.com/covid19vaccine-eua/
7. Pfizer-BioNTech COVID-19 Vaccine | cvdvaccine.com. Accessed December 19, 2020. https://www.cvdvaccine.com