Evidence Review of the Adverse Effects of COVID-19 Vaccination and Intramuscular Vaccine Administration (2024)
Chapter: Front Matter
Evidence Review of the
Adverse Effects of COVID-19
Vaccination and Intramuscular
Vaccine Administration
_____
Anne R. Bass, Kathleen Stratton,
Ogan K. Kumova, and Dara Rosenberg, Editors
Committee to Review Relevant Literature
Regarding Adverse Events Associated with Vaccines
Board on Population Health and
Public Health Practice
Health and Medicine Division
Consensus Study Report
THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001
This activity was supported by a contract between the National Academy of Sciences and Health Resources and Services Administration, which includes funds from the Centers for Disease Control and Prevention. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-71832-5
International Standard Book Number-10: 0-309-71832-5
Digital Object Identifier: https://doi.org/10.17226/27746
Library of Congress Control Number: 2024941529
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2024. Evidence review of the adverse effects of COVID-19 vaccination and intramuscular vaccine administration. Washington, DC: The National Academies Press. https://doi.org/10.17226/27746.
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COMMITTEE TO REVIEW RELEVANT LITERATURE REGARDING ADVERSE EVENTS ASSOCIATED WITH VACCINES
GEORGE J. ISHAM (Chair), Senior Fellow, HealthPartners Institute
ANNE R. BASS (Vice Chair), Professor of Clinical Medicine, Department of Medicine, Division of Rheumatology, Hospital for Special Surgery, Weill Cornell Medicine
ALICIA CHRISTY, Professor of Obstetrics and Gynecology, Uniformed Services University; Adjunct Professor, Howard University School of Medicine
DELISA FAIRWEATHER, Professor of Medicine, Director of Translational Research, Department of Cardiovascular Medicine; Codirector of Research for the Ehlers-Danlos Syndrome Clinic, Department of General Internal Medicine, Mayo Clinic (Jacksonville, FL)
JAMES S. FLOYD, Codirector of the Cardiovascular Health Research Unit, Associate Professor of Medicine, Adjunct Professor of Epidemiology, University of Washington
ERIC J. HEGEDUS, Professor and Chair, Department of Rehabilitation Science, Tufts University School of Medicine
CHANDY C. JOHN, Ryan White Professor of Pediatrics, Professor of Medicine, Professor of Microbiology and Immunology, Director of the Ryan White Center for Pediatric Infectious Diseases and Global Health, Indiana University School of Medicine
JOHN EDWARD KUHN, Schermerhorn Professor of Orthopaedic Surgery, Chief of Shoulder Surgery, Department of Orthopaedic Surgery, Vanderbilt University Medical Center
EVAN MAYO-WILSON, Associate Professor, Department of Epidemiology, University of North Carolina Gillings School of Global Public Health
THOMAS LEE ORTEL, Chief, Division of Hematology, Department of Medicine; Professor of Medicine and Pathology, Duke University School of Medicine
NICHOLAS S. REED, Assistant Professor, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health; Assistant Professor, Department of Otolaryngology, Division of Otology/Audiology, Johns Hopkins University School of Medicine
ANDY S. STERGACHIS, Professor and Associate Dean of Pharmacy, School of Pharmacy; Professor of Global Health, School of Public Health, University of Washington
MICHEL TOLEDANO, Assistant Professor of Neurology, Department of Neurology, Mayo Clinic (Rochester, MN)
ROBERT B. WALLACE, Irene Ensmenger Stecher Professor Emeritus of Epidemiology and Internal Medicine, University of Iowa
OUSSENY ZERBO, Research Scientist II, Vaccine Study Center, Division of Research, Kaiser Permanente Northern California
National Academy of Medicine Fellow
INMACULADA HERNANDEZ, Professor, San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California
Health and Medicine Division Staff
KATHLEEN STRATTON, Study Director
OGAN K. KUMOVA, Program Officer (since February 2023)
DARA ROSENBERG, Associate Program Officer
NERISSA HART, Senior Program Assistant (through May 2023)
OLIVIA LOIBNER, Senior Program Assistant (since June 2023)
MISRAK DABI, Finance Business Partner
REBECCA MORGAN, Senior Research Librarian
ANNE MARIE HOUPPERT, Senior Research Librarian
ROSE MARIE MARTINEZ, Senior Board Director, Board on Population Health and Public Health Practice
Reviewers
This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.
We thank the following individuals for their review of this report:
DOUGLAS B. CINES, Director, Coagulation Laboratory; Director, Office of Faculty Development, Pathology and Laboratory Medicine; Professor of Pathology and Laboratory Medicine (Hematology-Oncology), University of Pennsylvania School of Medicine
BETTY DIAMOND, Director, Institute of Molecular Medicine, The Feinstein Institutes for Medical Research North Shore-LIJ Health System, Northwell Health
KATHRYN EDWARDS, Professor of Pediatrics; Sarah H. Sell and Cornelius Vanderbilt Chair, Vanderbilt Vaccine Research Program, Vanderbilt University Medical Center
MARIE GRIFFIN, Professor Emerita, Vanderbilt University School of Medicine
AKIKO IWASAKI, Howard Hughes Medical Institute Investigator; Director, Center for Infection and Immunity; Sterling Professor of Immunobiology and Molecular, Cellular, and Developmental Biology, Yale University
EMILY JUNGHEIM, Chief of Reproductive Endocrinology and Infertility in the Department of Obstetrics and Gynecology, Northwestern University
GRACE M. LEE, Professor of Pediatrics, Stanford Medicine Children’s Health
TIANJING LI, Associate Professor, University of Colorado Anschutz Medical Campus
JENNIFER S. LIN, Distinguished Investigator, Kaiser Permanente Center for Health Research
CLAUDIA LUCCHINETTI, Dean, Dell Medical School; Senior Vice President for Medical Affairs, University of Texas at Austin
H. CODY MEISSNER, Professor of Pediatrics and Medicine, Geisel School of Medicine at Dartmouth; Senior Vaccine and Biologics Development Analyst, Biomedical Advanced Research and Development Authority; Administration for Strategic Preparedness and Response, U.S. Department of Health and Human Services
BRIAN OLSHANSKY, Emeritus Professor of Internal Medicine–Cardiovascular Medicine, Carver College of Medicine, University of Iowa, University of Iowa Hospitals and Clinics
JAMES SEGARS, Director, Division of Reproductive Sciences and Women’s Health Research, Johns Hopkins University School of Medicine
UMASUTHAN SRIKUMARAN, Assistant Professor, Orthopaedic Surgery, Johns Hopkins University
GRETA C. STAMPER, Audiology Division Chair, Audiology Externship Program Director, Consultant in Otorhinolaryngology, Mayo Clinic
Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report, nor did they see the final draft before its release. The review of this report was overseen by coordinator DAVID SAVITZ, Professor of Epidemiology, Brown University, and monitor WALTER FRONTERA, Professor of Physical Medicine, Rehabilitation, and Sports Medicine, University of Puerto Rico School of Medicine. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.
Acknowledgments
The Committee to Review Relevant Literature Regarding Adverse Events Associated with Vaccines and the committee staff would like to thank many individuals for their contributions throughout all phases of the study: Misrak Dabi (Finance Business Partner), Crysti Park (Program Coordinator), Lori Brenig (Editorial Projects Coordinator), Taryn Young (Report Review Associate), Leslie Sim (Senior Report Review Officer), Benjamin Hubbert (Communications Specialist), Amber McLaughlin (Director of Communications), Tasha Bigelow (Copy Editor), Rebecca Morgan (Senior Research Librarian), and Anne Marie Houppert (Senior Research Librarian).
The committee acknowledges and thanks the members of the public who provided valuable insight to the committee via email correspondence and in public comments.
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Contents
2 IMMUNOLOGIC RESPONSE TO COVID-19 VACCINES
Fundamentals of the Immune Response
SARS-CoV-2 and Vaccine Target of the Spike Protein
Vaccine Immune Response Elicitation
Possible Mechanisms of Vaccine-Mediated Reactions
3 NEUROLOGIC CONDITIONS AND COVID-19 VACCINES
Chronic Inflammatory Demyelinating Polyneuropathy
4 SENSORINEURAL HEARING LOSS, TINNITUS, AND COVID-19 VACCINES
Thrombosis with Thrombocytopenia Syndrome
Immune Thrombocytopenic Purpura
Deep Vein Thrombosis, Pulmonary Embolism, and Venous Thromboembolism
7 MYOCARDITIS, PERICARDITIS, AND COVID-19 VACCINES
Epidemiology of Myocarditis and Pericarditis
COVID-19 Vaccines: Clinical and Epidemiological Evidence
8 SUDDEN DEATH AND COVID-19 VACCINES
9 FEMALE INFERTILITY AND COVID-19 VACCINES
Clinical and Epidemiological Evidence
10 SHOULDER INJURIES AND VACCINES
Subacromial/Subdeltoid Bursitis
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Boxes, Figures, and Tables
BOXES
3-1 Conclusions for Guillain-Barré Syndrome
3-2 Conclusions for Chronic Inflammatory Demyelinating Polyneuropathy
3-3 Conclusions for Bell’s Palsy
3-4 Conclusions for Transverse Myelitis
3-5 Conclusions for Chronic Headache
3-6 Conclusions for Postural Orthostatic Tachycardia Syndrome
4-1 Conclusions for Sensorineural Hearing Loss
5-1 Conclusions for Thrombosis with Thrombocytopenia Syndrome
5-2 Conclusions for Immune Thrombocytopenic Purpura
5-3 Conclusions for Capillary Leak Syndrome
6-1 Conclusions for Myocardial Infarction
6-2 Conclusions for Ischemic Stroke
6-3 Conclusions for Hemorrhagic Stroke
6-4 Conclusions for Deep Vein Thrombosis, Pulmonary Embolism, and Venous Thromboembolism
9-1 Conclusions for Female Infertility
10-1 Conclusions for Shoulder Injuries
11-1 Conclusions Regarding BNT162b2
11-2 Conclusions Regarding mRNA-1273
11-3 Conclusions Regarding Ad26.COV2.S
11-4 Conclusions Regarding NVX-CoV2373
11-5 Conclusions Regarding Shoulder Injuries
11-6 Conclusions for Which the Evidence Establishes a Causal Relationship
11-7 Conclusions for Which the Evidence Favors Acceptance of a Causal Relationship
11-8 Conclusions for Which the Evidence Favors Rejection of a Causal Relationship
FIGURES
2-1 COVID-19 vaccines contributing to this report and their mechanism of action
2-2 Immune responses to intramuscular administration of SARS-CoV-2 mRNA vaccines
10-1 Illustration of intramuscular injection techniques
TABLES
S-1 Causal Conclusions Regarding COVID-19 Vaccines
S-2 Conclusions Regarding Shoulder Injuries After Any Vaccination
1-1 COVID-19 Vaccines Used in the United States
2-1 Immune Responses to U.S. COVID-19 Vaccines
2-2 Vaccine-Mediated Reactions and Their Mechanisms
2-3 Most Commonly Used Adjuvants in Vaccines
3-1 Epidemiological Studies in the Guillain-Barré Syndrome Evidence Review
3-2 Pharmacovigilance Studies in the Guillain-Barré Syndrome Evidence Review
3-3 Epidemiological Study in the Chronic Inflammatory Demyelinating Polyneuropathy Evidence Review
3-4 Epidemiological Studies in the Bell’s Palsy Evidence Review
3-5 Epidemiological Studies in the Transverse Myelitis Evidence Review
3-6 Epidemiological Study in the Postural Orthostatic Tachycardia Syndrome Evidence Review
4-1 Epidemiological Studies in the Sensorineural Hearing Loss Evidence Review
4-2 Epidemiological Studies in the Tinnitus Evidence Review
5-1 Epidemiological Studies in the Thrombosis with Thrombocytopenia Evidence Review
5-2 Epidemiological Studies in the Immune Thrombocytopenic Purpura Evidence Review
6-1 Epidemiological Studies in the Vascular Conditions Evidence Review
6-2 Epidemiological Studies in the BNT162b2–Myocardial Infarction Evidence Review
6-3 Epidemiological Studies in the mRNA-1273–Myocardial Infarction Evidence Review
6-4 Epidemiological Study in the Ad26.COV2.S–Myocardial Infarction Evidence Review
6-5 Epidemiological Studies in the BNT162b2–Ischemic Stroke Evidence Review
6-6 Epidemiological Study in the mRNA-1273–Ischemic Stroke Evidence Review
6-7 Epidemiological Study in the Ad26.COV2.S–Ischemic Stroke Evidence Review
6-8 Epidemiological Studies in the BNT162b2–Hemorrhagic Stroke Evidence Review
6-9 Epidemiological Study in the mRNA-1273–Hemorrhagic Stroke Evidence Review
6-10 Epidemiological Study in the Ad26.COV2.S–Hemorrhagic Stroke Evidence Review
6-11 Epidemiological Studies in the BNT162b2–Deep Vein Thrombosis Evidence Review
6-12 Epidemiological Studies in the BNT162b2–Pulmonary Embolism Evidence Review
6-13 Epidemiological Studies in the mRNA–1273–Pulmonary Embolism Evidence Review
6-14 Epidemiological Study in the Ad26.COV2.S–Pulmonary Embolism Evidence Review
6-15 Epidemiological Studies in the BNT162b2–Venous Thromboembolism Evidence Review
7-1 Findings from Canada’s Strategy for Patient-Oriented Research
7-2 Selected Epidemiological Studies of Risk of Myocarditis Associated with BNT162b2
7-3 Selected Epidemiological Studies of Risk of Pericarditis Associated with BNT162b2
7-5 Selected Epidemiological Studies of Risk of Myocarditis Associated with mRNA-1273
7-6 Selected Epidemiological Studies of Risk of Pericarditis Associated with mRNA-1273
8-1 Epidemiological Study in the Sudden Death Evidence Review
9-1 Clinical and Epidemiological Studies in the Female Infertility Evidence Review
10-1 Case Reports Regarding Subacromial/Subdeltoid Bursitis After Vaccination
10-2 Case Reports of Acute Rotator Cuff or Acute Biceps Tendinopathy After Vaccination
10-3 Case Reports of Adhesive Capsulitis After Vaccination
10-4 Case Reports of Septic Arthritis After Vaccination
10-5 Case Reports of Bone Injury After Vaccination
10-6 Case Reports of Axillary or Radial Nerve Injury After Vaccination
10-7 Case Reports of Parsonage-Turner Syndrome After Vaccination
10-8 Budapest Criteria to Diagnose Complex Regional Pain Syndrome
10-9 Case Reports of Complex Regional Pain Syndrome After Vaccination
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Preface
In the 4 years since the first case of COVID-19 was recognized and after a pandemic was declared by the World Health Organization 3 months later in March 2020, an estimated 3.5 million died from SARS-CoV-2 infection. Millions more became ill, and some have suffered long-term effects (“long COVID”) that are not yet understood fully. Aside from its health impact, the pandemic has caused marked social, economic, and political upheaval. We doubt any have had lives unchanged by COVID-19.
The response to the pandemic has been extraordinary. By spring 2021, only 1 year after the pandemic declaration, vaccines authorized by the Food and Drug Administration for emergency use were being administered across the United States, indeed, around the world. It is estimated that more than 14 million lives were saved in the year after vaccines became available, with one death avoided for every 124 full vaccination courses. Lives were also saved by other public health interventions and often-heroic efforts of health care workers and health care systems.
In the 3 years since vaccines against SARS-CoV-2 came into use, their safety and efficacy have been established. Booster vaccinations and vaccines targeting new SARS-CoV-2 strains have been introduced and are now administered routinely alongside other vaccinations such as for influenza. While local, nonserious side effects, such as malaise or sore arm, are seen as with any vaccine, in rare instances, serious adverse events thought to be linked to SARS-CoV-2 vaccination have been noted.
The National Academies of Sciences, Engineering, and Medicine (the National Academies) have long tackled challenging questions about vaccine safety, beginning with an assessment of the oral polio vaccine in 1977. When Congress enacted the National Childhood Vaccine Injury Act in 1986, it charged the Institute of Medicine (IOM) with reviewing the literature regarding adverse events associated with vaccines covered by the program. The IOM1 has addressed questions about the safety of routinely administered vaccines 11 times since then. Following in this tradition, the National Academies tasked this consensus committee to assess the scientific evidence dispassionately regarding a list of harms potentially associated with vaccination against SARS-CoV-2, as well as an important potential harm associated with the administration of any vaccine, shoulder injury.
Thanks to the extraordinary efforts of investigators around the world who rapidly pivoted their research efforts to focus on this new virus (including its treatment and prevention), we now have a large body of evidence to consider. However, despite that large body of evidence, our consensus committee found that in many, if not most,
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1 As of March 2016, the Health and Medicine Division continues the consensus studies and convening activities previously carried out by the Institute of Medicine (IOM).
cases, the evidence was insufficient to accept or reject causality for a particular potential harm from a specific COVID-19 vaccine. In other cases, however, the committee considered the evidence to be sufficient to “favor rejection” of, to “favor acceptance” of, or to “establish causality.”
Limitations inherent in applying population-level average effects to draw conclusions about causes of specific events in individual subjects exist. For this reason, there is asymmetry in the committee’s conclusions, with options to conclude that the evidence “establishes a causal relationship,” “favors acceptance of causal relationship,” or “favors rejection of a causal relationship,” but not one to “establish rejection of a causal relationship.”
For every potential harm assessed, the committee evaluated the totality of evidence and did not apply what could be seen as arbitrary rules or thresholds regarding the number or types of studies required to draw conclusions. For the evaluation of select postulated vaccine harms, some study types were simply not available or were uninformative. For some cases, there was strong mechanistic as well as epidemiologic evidence supporting a causal relationship (e.g., thrombosis with thrombocytopenia syndrome), while, in others, the evidence was drawn largely from case reports.
COVID-19 has, understandably, dominated headlines over the past 3 years, yet routine vaccinations, such as for seasonal influenza, are still given. The harms our committee was tasked to review were those for which the Health Resources and Services Administration had claims for compensation. Perhaps surprisingly, only a minority of these claims related to SARS-CoV-2 vaccination. In fact, over 60 percent of claims focused on shoulder injury associated with intramuscular vaccine administration.
The term “SIRVA” (shoulder injury related to vaccine administration) has been introduced into the literature in recent years and was included in the committee’s Statement of Task. However, the term “SIRVA” encompasses many disparate shoulder conditions, and due to its lack of precision, the committee decided to dispense with this terminology. Instead, the committee addressed potential causal relationships between vaccine administration and specific shoulder-related medical diagnoses (e.g., subacromial bursitis, radial nerve injury).
This report does not address benefits of vaccination against SARS-CoV-2 or other pathogens, and readers will hopefully view causality findings in that broader context. Even when evidence of causality was established for some harms, the frequency of these harms was low. However, this report explicitly does not attempt to define point estimates for levels of risk.
Many talented, knowledgeable individuals volunteered hours of their time to analyze and report the evidence. Initially strangers, the members of this committee worked through difficult methodological questions together, at times engaging in spirited debate. In the process, we learned from one another, became a team, and became friends. Equally important, members of that team were the committee staff—Dara Rosenberg, Ogan Kumova, and Olivia Loibner, led by the incredibly wise and knowledgeable Kathleen Stratton and Rose Marie Martinez. The staff worked tirelessly every step of the way, providing indispensable support and guidance, and contributing greatly to the report itself.
This is not the first HMD/National Academies report regarding vaccine safety. Nor will it be the last. We anticipate new vaccines and expect that ongoing and future scientific research may challenge the findings reported here. This report necessarily reflects a snapshot in time, albeit a momentous one, and represents our best effort to report the truth.
George J. Isham, Chair
Anne R. Bass, Vice Chair
Committee to Review Relevant Literature Regarding
Adverse Events Associated with Vaccines
Acronyms and Abbreviations
| AAOS | American Academy of Orthopaedic Surgeons |
| ACE2 | angiotensin-converting enzyme 2 |
| ADE | antibody dependent enhancement |
| ADEM | acute disseminated encephalomyelitis |
| AFC | antral follicle count |
| AIDP | acute inflammatory demyelinating polyneuropathy |
| AMAN | acute motor axonal neuropathy |
| AMH | anti-Müllerian hormone |
| AV | adenovirus vector |
| BP | Bell’s palsy |
| bpm | beats per minute |
| CAR | coxsackie and adenoviral receptor |
| CDC | Centers for Disease Control and Prevention |
| CGRP | calcitonin gene–related peptide |
| CI | confidence interval |
| CICP | Countermeasures Injury Compensation Program |
| CIDP | chronic inflammatory demyelinating polyneuropathy |
| CLS | capillary leak syndrome |
| CPRD | Clinical Practice Research Datalink |
| CRPS | complex regional pain syndrome |
| CSF | cerebrospinal fluid |
| CT | computed tomography |
| CVST | cerebral venous sinus thrombosis |
| DCM | dilated cardiomyopathy |
| DNA | deoxyribonucleic acid |
| DTaP | diphtheria, tetanus, and acellular pertussis vaccine |
| DVT | deep vein thrombosis |
| EMG | electromyogram |
| EMR | electronic medical record |
| EUA | Emergency Use Authorization |
| EV | extracellular vesicle |
| FDA | Food and Drug Administration |
| FR | fecundity rate |
| FSH | follicle-stimulating hormone |
| GBS | Guillain-Barré syndrome |
| GC | germinal center |
| HIT | heparin-induced thrombocytopenia |
| HLA | human leukocyte antigen |
| HPV | human papillomavirus |
| HR | hazard ratio |
| HRSA | Health Resources and Services Administration |
| HS | hemorrhagic stroke |
| HSV | herpes simplex virus |
| ICD | International Classification of Diseases |
| ICHD | International Classification of Headache Disorders |
| IFN | interferon |
| Ig | immunoglobulin |
| IL | interleukin |
| IOM | Institute of Medicine |
| IQR | interquartile range |
| IR | incidence rate |
| IRR | incidence rate ratio |
| ITP | immune thrombocytopenic purpura |
| IV | intravenous |
| LH | luteinizing hormone |
| LLPC | long-lived plasma cell |
| LNP | lipid nanoparticle |
| MI | myocardial infarction |
| MRI | magnetic resonance imaging |
| mRNA | messenger ribonucleic acid |
| MS | multiple sclerosis |
| NCS | nerve conduction study |
| NCVIA | National Childhood Vaccine Injury Act |
| NIH | National Institutes of Health |
| NR | not reported |
| O:E | observed-to-expected ratio |
| OHCA | out-of-hospital cardiac arrest |
| OPV | oral polio vaccine |
| OR | odds ratio |
| PE | pulmonary embolism |
| PF4 | platelet factor 4 |
| POTS | postural orthostatic tachycardia syndrome |
| PPV | positive predictive value |
| PTS | Parsonage-Turner syndrome |
| RBD | receptor-binding domain |
| RCT | randomized controlled trial |
| RI | relative incidence |
| RNA | ribonucleic acid |
| RR | relative risk or risk ratio |
| RSV | respiratory syncytial virus |
| SARS-CoV-2 | severe acute respiratory syndrome coronavirus-2 |
| SCCS | self-controlled case series |
| SHBG | sex hormone binding globulin |
| SIDIAP | Information System for the Development of Research in Primary Care |
| SIR | standardized incidence ratio |
| SIRVA | shoulder injury related to vaccine administration |
| SPOR | Strategy for Patient-Oriented Research |
| SSNHL | sudden sensorineural hearing loss |
| SSP | supraspinatus |
| SUD | sudden unexpected death |
| Tfh | T follicular helper |
| TLR | Toll-like receptor |
| TM | transverse myelitis |
| TNF | tumor necrosis factor |
| TTH | tension-type headache |
| TTS | thrombosis with thrombocytopenia syndrome |
| UI | uncertainty interval |
| VAED | vaccine-associated enhanced disease |
| VAERS | Vaccine Adverse Event Reporting System |
| VICP | Vaccine Injury Compensation Program |
| VITT | vaccine-induced immune thrombotic thrombocytopenia |
| VSD | Vaccine Safety Datalink |
| VTE | venous thromboembolism |
| WHO | World Health Organization |
| YLD | years lived with disability |
| YLL | years of life lost |
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