top of page

COVID-19 Vaccine and SARS CoV-2 Mutational Variant Update

Eligible for CME Credit

Online Test on

by Stuart M. Caplen MD

Vaccines were created and produced in record time in 2020 to combat COVID-19. As of May 2021, there are 14 vaccines either approved fully or for emergency use around the world. 27 vaccines are in phase 3 testing and 85 in phase 1 or 2 testing. Three are currently approved for use in the United States.[1] Given the vast number of vaccines in the pipeline, in the future there may be a tsunami of new vaccines to choose from. In addition, some SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) mutational variants are increasingly more infective, and potentially resistant to current vaccines. Here is what is known now.

Pfizer/BioNTech RNA vaccine (Tozinameran or BNT162b2)

The Pfizer/Biontech vaccine, also called tozinameran, or BNT162b2, is an RNA vaccine which uses replicated parts of the SARS-CoV-2 virus’s RNA to induce an immune response. It was approved by the FDA on December 11, 2020 for emergency use in two doses, three weeks apart.[1] Initially, it was found to have 95% efficacy in preventing infection.[1] A more recent Pfizer press release, of yet unpublished data on 12,000 study participants, reported that the BNT162b2 vaccine had an efficacy of 91.3% against COVID-19, measured seven days to six months after the second dose. It was 100% effective against severe disease according to CDC criteria, and 95.3% effective against severe disease according to FDA criteria (FDA criteria has some clinical measurements in its definition to explain some of the difference.[2]). The vaccine was 100% effective in preventing COVID-19 cases in South Africa, where the B.1.351 lineage is prevalent.[3]

In clinical studies, adverse reactions from this vaccine included…….


Read the conclusion on about the 3 Covid-19 vaccines currently approved for use in the US and a summary of a few of the critical variants.

Members Click Here to Read the Conclusion and Take the CME Test

Not a member? Click Here to Learn About Our Membership Options

#COVID19 #FibonacciCME

FibonacciMD has articles like Everything You Wanted to Know About Masks in the Time of COVID

And more COVID-19 articles


Use our Groundbreaking Medical Search Compendium or Annotate your EMR, PDFs, and docs on


Stuart M. Caplen, MD, FACEP, MSM

Dr. Caplen is a former emergency physician and emergency department medical director, now retired from clinical practice. His current interests include how quality is produced and maintained in health care, and he has greenbelt certification in lean/six sigma.


[1] Zimmer C et al. Coronavirus Vaccine Tracker, The New York Times,Updated April 20, 2021. Retrieved from:

[2] COVID-19: Developing Drugs and Biological Products for Treatment or Prevention Guidance for Industry, U.S. Department of Health and Human Services Food and Drug Administration, February 2021. Retrieved from:

[3] Pfizer and BioNTech Confirm High Efficacy and No Serious Safety Concerns Through Up to Six Months Following Second Dose in Updated Topline Analysis of Landmark COVID-19 Vaccine Study, Pfizer, April 01, 2021. Retrieved from:

[4] Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine — United States, December 14–23, 2020, CDC, Morbidity and Mortality Weekly Report, January 15, 2021 / 70(2);46–51. Retrieved from:

[4A] Vaccines and Related Biological Products Advisory Committee Meeting December 10, 2020. FDA Briefing Document Pfizer-BioNTech COVID-19 Vaccine. Retrieved from:

[5] Dagan N et al. BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting, The NEJM, N Engl J Med 2021; 384:1412-1423, April 15, 2021. Retrieved from:

[6] Moderna Provides Clinical and Supply Updates on COVID-19 Vaccine Program Ahead of 2nd Annual Vaccines Day. Moderna Press Release, April 13, 2021. Retrieved from:

[7] Doria-Rose N et al. Correspondence: Antibody Persistence through 6 Months after the Second Dose of mRNA-1273 Vaccine for Covid-19, April 6, 2021. Retrieved from:

[8] Vaccines and Related Biological Products Advisory Committee Meeting, FDA Briefing Document, Moderna, December 17, 2020. Retrieved from:

[9] Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Moderna COVID-19 Vaccine — United States, December 21, 2020–January 10, 2021, CDC, Morbidity and Mortality Weekly Report, January 29, 2021 / 70(4);125–129. Retrieved from:

[10] Blumenthal KG et al. Delayed Large Local Reactions to mRNA-1273 Vaccine against SARS-CoV-2, NEJM, N Engl J Med 2021; 384:1273-1277, April 1, 2021. Retrieved from:

[11] AZD1222 US Phase III trial met primary efficacy endpoint in preventing COVID-19 at interim analysis, AstraZenica, March 22, 2021. Retrieved from:

[12] Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant, NEJM, March 16, 2021. Retrieved from:

[13] Scully M et al. Pathologic Antibodies to Platelet Factor 4 after ChAdOx1 nCoV-19 Vaccination, NEJM, April 16, 2021. Retrieved from:

[14] Greinacher A, Towards Understanding ChAdOx1 nCov-19 Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT), Research Square, April 20,2021. Retrieved from:

[15] Kaplan MJ, Radic M, Neutrophil extracellular traps: double-edged swords of innate immunity.” Journal of immunology (Baltimore, Md. : 1950) vol. 189,6 (2012): 2689-95. Retrieved from:

[16] Cines D, Bussel J, SARS-CoV-2 Vaccine–Induced Immune Thrombotic Thrombocytopenia, NEJM, April 16, 2021. Retrieved from:

[17] Carl Zimmer and Emily Anthes,A C.D.C. panel recommends J.&J. shots restart with a label noting the risk of very rare blood clots, The New York Times, April 23, 2021. Retrieved from:

[17A] Anthes E, The C.D.C. confirms more cases of a rare blood clot disorder linked to the J.&J. vaccine., The New York Times, May 12, 2021. Retrieved from:

[18] Roy P, Jones I, Sputnik V COVID-19 vaccine candidate appears safe and effective, The Lancet,Volume 397, ISSUE 10275, P642-643, February 20, 2021, First Published: February 02, 2021. Retrieved from:

[18A] Lowe D, Brazil Rejects the Gamaleya Vaccine, Science Translational Medicine, April 28, 2021. Retrieved from:

[18B] Andreoni M, Pietsch B, Brazil’s health authority rejects importing Russia’s Sputnik V vaccine, The New York Times, April 26, 2021.

[19] Lehman C et al. Unilateral Lymphadenopathy Post COVID-19 Vaccination: A Practical Management Plan for Radiologists Across Specialties, J Am Coll Radiol 2021, March 4, 2021. Retrieved from:

[20] Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Authorized in the United States, CDC, last updated April 16, 2021. Retrieved from:

[21] Mandavilli A, Vaccines Won’t Protect Millions of Patients With Weakened Immune Systems, The New York Times, Published April 15, 2021Updated April 16, 2021.

[22] Lilly's neutralizing antibody bamlanivimab (LY-CoV555) prevented COVID-19 at nursing homes in the BLAZE-2 trial, reducing risk by up to 80 percent for residents, Eli Lilly news release, January21,2020. Retrieved from:

[23] Murphy T, Lilly: Drug can prevent COVID-19 illness in nursing homes, AP, January21,2021. Retrieved from:

[24] Shimabukuro T et al. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons, NEJM, April 21, 2021. Retrieved from:

[25] Caplen S, COVID-19 Mutations, Human Genetic Variation, and the Resulting Clinical Effects, FibonacciMD, Jul 16, 2020. Retrieved from:

[26] Corum J, Zimmer C, How Coronavirus Hijacks Your Cells, The New York Times, Updated March 13, 2020. Retrieved from:

[27] Clancy, S, Brown W, Translation: DNA to mRNA to Protein. Nature Education, 2008, 1(1):101. Retrieved from:

[28] Sturm N, DNA Mutation and Repair, 2019. Retrieved from:

[29] Mandal A, SARS-CoV-2 emergence could be due to genetic selection and recombination, News Medical Life Sciences, , Jun 1 2020. Retrieved from

[30] Li X, et al., Emergence of SARS-CoV-2 through recombination and strong purifying selection, Science Advances, July 1, 2020. Retrieved from:

[31] B.1.135? B.1.1.7? Why the coronavirus variants names don't make sense—and how we can do better., Advisory Board, March 4, 2021. Retrieved from:

[32] Faria NR et al. "Genomic characterisation of an emergent SARS-CoV-2 lineage in Manaus: preliminary findings". CADDE Genomic Network., January 12, 2021. Retrieved from:

[33] Callaway E, ‘A bloody mess’: Confusion reigns over naming of new COVID variants, Nature, January 15, 2021. Retrieved from:

[34] Tseng A et al. New COVID-19 In-Depth Report: Summary of SARS-CoV-2 Novel Variants, University of Washington, Dept. of Global Health, February 08, 2021. Retrieved from:

[35] COVID Data Tracker, Estimates of SARS-CoV-2 Prevalence, CDC, Data through 4/10/21.Retreived from:

[36] Parker-Pope T, Can the Covid Vaccine Protect Me Against Virus Variants?, The New York Times, Published April 15, 2021, Updated April 19, 2021. Retrieved from:

[37] Jonathan Corum and Carl Zimmer, Coronavirus Variants and Mutations, The New York Times, Updated April 26, 2021. Retrieved from:

[38] SARS-CoV-2 Variant Classifications and Definitions, CDC, Updated Apr. 21, 2021. Retrieved from:

[39] Wu K et al. Correspondence: Serum Neutralizing Activity Elicited by mRNA-1273 Vaccine,N Engl J Med 2021; 384:1468-1470, April 15, 2021. Retrieved from:

[40] Collier D, Sensitivity of SARS-CoV-2 B.1.1.7 to mRNA vaccine-elicited antibodies, Nature, March 11, 2021. Retrieved from:

[41] Kustin t et al. Evidence for increased breakthrough rates of SARS-CoV-2 variants of concern in BNT162b2 mRNA vaccinated individuals,medRxiv 2021.04.06. Retrieved from:

[42] Liu Y et al. Correspondence: Neutralizing Activity of BNT162b2-Elicited Serum, N Engl J Med 2021; 384:1466-1468, April 15, 202. Retrieved from:


IMIT takes pride in its work, and the information published on the IMIT Platform is believed to be accurate and reliable. The IMIT Platform is provided strictly for informational purposes, and IMIT recommends that any medical, diagnostic, or other advice be obtained from a medical professional. Read full disclaimer.

bottom of page