Welcome to the CCO Site

Thank you for your interest in CCO content. As a guest, please complete the following information fields. These data help ensure our continued delivery of impactful education. 

Become a member (or login)? Member benefits include accreditation certificates, downloadable slides, and decision support tools.


Frequently Asked Questions on COVID-19 Vaccines and Immunity

Sharon R. Lewin, AO, FRACP, PhD, FAHMS
Jens D. Lundgren, MD, DMSc
Vikramjit Mukherjee, MD
Roger Paredes, MD, PhD
Released: December 29, 2020
Back Next


Aran D. Estimating real-world COVID-19 vaccine effectiveness in Israel. Preprint available at: https://www.medrxiv.org/content/10.1101/2021.02.05.21251139v1. Accessed April 5, 2021. Note: This study has not been peer reviewed.

Arvin AM, Fink K, Schmid MA, et al. A perspective on potential antibody-dependent enhancement of SARS-CoV-2. Nature. 2020;584:353-363.

Byambasuren O, Cardona M, Bell K, et al. Estimating the extent of asymptomatic COVID-19 and its potential for community transmission: systematic review and meta-analysis. Preprint available at: https://www.medrxiv.org/content/10.1101/2020.05.10.20097543v3. Accessed April 5, 2021. Note: This study has not been peer reviewed.

Centers for Disease Control and Prevention. New COVID-19 Variants. January 15, 2021. Available at: https://www.cdc.gov/coronavirus/2019-ncov/transmission/variant.html. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Moderna COVID-19 vaccine. December 22, 2020. Available at: https://www.cdc.gov/vaccines/covid-19/info-by-product/moderna/index.html. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Pfizer-BioNTech COVID-19 vaccine. February 16, 2021. Available at: https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/index.html. Accessed April 5, 2021.

Center for Disease Control and Prevention. Interim public health recommendations for fully vaccinated people. March 8, 2021. Available at: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated-guidance.html. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Vaccination considerations for people who are pregnant or breastfeeding. February 12, 2021. Available at: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/recommendations/pregnancy.html. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Allergic reactions including anaphylaxis after receipt of the first dose of Pfizer-BioNTech COVID-19 vaccine — United States, December 14-23, 2020. January 15, 2021. Available at: https://www.cdc.gov/mmwr/volumes/70/wr/mm7002e1.htm. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Allergic reactions including anaphylaxis after receipt of the first dose of Moderna COVID-19 vaccine — United States, December 21, 2020-January 10, 2021. January 22, 2021. Available at: https://www.cdc.gov/mmwr/volumes/70/wr/mm7004e1.htm?s_cid=mm7004e1_w. Accessed April 5, 2021.

Centers for Disease Control and Prevention. Interim clinical considerations for use of mRNA COVID-19 vaccines currently authorized in the United States. Available at: https://www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fvaccines%2Fcovid-19%2Finfo-by-product%2Fpfizer%2Fclinical-considerations.html. Accessed April 5, 2021.

Centers for Disease Control and Prevention. COVID-19 vaccines and severe allergic reactions. Available at: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/allergic-reaction.html. Accessed April 5, 2021.

ClinicalTrials.gov. Study to describe the safety, tolerability, immunogenicity, and efficacy of RNA vaccine candidates against COVID-19 in healthy individuals. Available at: https://clinicaltrials.gov/ct2/show/NCT04368728. Accessed April 5, 2021.

Dagan M, Barda, M, Kepten E, et al. BNT162b2 mRNA COVID-19 vaccine in a nationwide mass vaccination setting. N Engl J Med. 2021;[Epub ahead of print].

Edridge AWD, Kaczorowska J, Hoste ACR, et al. Seasonal coronavirus protective immunity is short-lasting. Nat Med. 2020;26:1691-1693.

Esteve C, Catherine FX, Chavanet P, et al. How should a positive PCR test result for COVID-19 in an asymptomatic individual be interpreted and managed? Med Mal Infect. 2020;50:633.

Goldman JD, Wang K, Roltgen K, et al. Reinfection with SARS-CoV-2 and failure of humoral immunity: a case report. Preprint available at: https://www.medrxiv.org/content/10.1101/2020.09.22.20192443v1. Accessed April 5, 2021. Note: This study has not been peer reviewed.

Hobbs CV, Khaitan A, Kirmse BM, et al. COVID-19 in children: A review and parallels to other hyperinflammatory syndromes. Front Pediatr. 2020;8:593455.

Ibarrondo FJ, Fulcher JA, Goodman-Meza D, et al. Rapid decay of anti-SARS-CoV-2 antibodies in persons with mild COVID-19. N Engl J Med. 2020;383:1085-1087.

Jackson LA, Anderson EJ, Rouphael NG, et al. An mRNA vaccine against SARS-CoV-2—preliminary report. N Engl J Med. 2020;383:1920-1931.

Johnson & Johnson, Inc. Johnson and Johnson COVID-19 vaccine authorized by US FDA for emergency use- first single-shot vaccine in fight against global pandemic. Press release. February 27, 2021. Available at: https://www.jnj.com/johnson-johnson-covid-19-vaccine-authorized-by-u-s-fda-for-emergency-usefirst-single-shot-vaccine-in-fight-against-global-pandemic. Accessed April 5, 2021.

Lee WS, Wheatley AK, Kent SJ, et al. Antibody-dependent enhancement and SARS-CoV-2 vaccines and therapies. Nat Microbiol. 2020;5:1185-1191.

Moderna, Inc. Moderna announces it has shipped variant-specific vaccine candidate, mRNA-1273.351, to NIH for clinical study. Press release. February 24, 2021. Available at: https://investors.modernatx.com/news-releases/news-release-details/moderna-announces-it-has-shipped-variant-specific-vaccine. Accessed April 5, 2021.

Moderna, Inc. Moderna COVID-19 vaccine retains neutralizing activity against emerging variants first identified in the U.K. and the Republic of South Africa. Press release. January 25, 2021. Available at: https://investors.modernatx.com/news-releases/news-release-details/moderna-covid-19-vaccine-retains-neutralizing-activity-against. Accessed April 5, 2021

Moderna, Inc. Moderna announces primary efficacy analysis in phase 3 COVE study for its COVID-19 vaccine candidate and filing today with US FDA for emergency use authorization. Press release. November 30, 2020. Available at: https://investors.modernatx.com/news-releases/news-release-details/moderna-announces-primary-efficacy-analysis-phase-3-cove-study. Accessed April 5, 2021.

Mulligan MJ, Lyke KE, Kitchin N, et al. Phase I/II study of COVID-19 RNA vaccine BNT162b1 in adults. Nature. 2020;586:589-593.

Pfizer Inc. Pfizer and BioNtech publish results of study showing COVID-19 vaccine elicits antibodies that neutralize pseudovirus bearing the SARS-CoV-2 U.K. strain spike protein in cell culture. Press release. January 20, 2021. Available at: https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-puresults-study-showing-covid-19. Accessed April 5, 2021.

Pfizer Inc. Pfizer and BioNTech conclude phase 3 study of COVID-19 vaccine candidate, meeting all primary efficacy endpoints. Press release. November 18, 2020. Available at: https://www.businesswire.com/news/home/20201118005595/en/. Accessed April 5, 2021.

Pollack FC, Thomas SJ, Kitchin, N, et al. Safety and efficacy of the BNT162b2 mRNA COVID-19 vaccine. N Engl J Med. 2020;383:2603-2615.

Sadoff J, Le Gars M, Shukarev G, et al. Interim results of a phase 1-2a trial of Ad26.COV2.S Covid-19 vaccine. N Engl J Med. 2021;[Epub ahead of print].

Sariol A, Perlman S. Lessons for COVID-19 immunity from other coronavirus infections. Immunity. 2020;53:248-263.

Shukla R, Ramasamy V, Shanmugam RK, et al. Antibody-dependent enhancement: A challenge for developing a safe dengue vaccine. Front Cell Infect Microbiol. 2020;10:572681.

Tang MW, Shafer RW. HIV-1 antiretroviral resistance: scientific principles and clinical applications. Drugs. 2012;72:e1-25.

Tillett RL, Sevinsky JR, Hartley PD, et al. Genomic evidence for reinfection with SARS-CoV-2: a case study. Lancet Infect Dis. 2020;21:52-58.

To KK, Hung IF, Ip JD, et al. COVID-19 re-infection by a phylogenetically distinct SARS-coronavirus-2 strain confirmed by whole genome sequencing. Clin Infect Dis. 2020;[Epub ahead of print].

US Food and Drug Administration. FDA statement on following the authorized dosing schedules for COVID-19 vaccines. January 4, 2021. Available at: https://www.fda.gov/news-events/press-announcements/fda-statement-following-authorized-dosing-schedules-covid-19-vaccines. Accessed April 5, 2021.

US Food and Drug Administration. Coronavirus (COVID-19) update: FDA authorizes first test that detects neutralizing antibodies from recent or prior SARS-CoV-2 infection. November 6, 2020. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-first-test-detects-neutralizing-antibodies-recent-or#:~:text=Binding%20antibodies%20bind%20to%20a,it%20is%20still%20being%20researched. Accessed April 5, 2021.

US Food and Drug Administration Briefing Document: Moderna COVID-19 vaccine. Available at: https://www.fda.gov/media/144434/download. Accessed April 5, 2021.

Wadhwa A, Aljabbari A, Lokras A, et al. Opportunities and challenges in the delivery of mRNA-based vaccines. Pharmaceutics. 2020;12:102.

Wang Y, Li J, Li H, Lei P, Shen G, Yang C. Persistence of SARS-CoV-2-specific antibodies in COVID-19 patients. Int Immunopharmacol. 2020;2;90:107271. 

Widge AT, Rouphael NG, Jackson LA, et al. Durability of responses after SARS-CoV-2 mRNA-1273 vaccination. N Engl J Med. 2021;384:80-82.

Back Next
Provided by Clinical Care Options, LLC

Contact Clinical Care Options

For customer support please email: customersupport@cealliance.com

Mailing Address
Clinical Care Options, LLC
12001 Sunrise Valley Drive
Suite 300
Reston, VA 20191

Educational grant provided by
Gilead Sciences, Inc.

Leaving the CCO site

You are now leaving the CCO site. The new destination site may have different terms of use and privacy policy.