Decoding the Human Genetic and Immunological Basis of COVID-19 mRNA Vaccine-Induced Myocarditis

Short- and long-term outcomes of cardiac adverse events following COVID-19 immunization managed in a Canadian pediatric center

BACKGROUND

Numerous reports have described the clinical presentation of cardiac adverse events following immunization (AEFI) with COVID-19 vaccines but long-term outcome studies are limited, especially in the pediatric population.

METHODS

This is a single center retrospective case series of pediatric patients with cardiac AEFI following the Pfizer/BioNTech mRNA COVID-19, diagnosed between May 2021 and May 2022, and managed following a standardized protocol. Follow up information is presented up to 12 months post diagnosis. The incidence rate of cardiac AEFI was estimated for Ottawa residents.

RESULTS

All cases were male (N = 17) with an average age of 16 years (range = 12-17). The majority of cases occurred after the 2nd (12/17) or 3rd vaccine dose (4/17) and were manifested mostly as myopericarditis (15/17). Average interval between the 1st and 2nd vaccine (n = 12) doses was 38 days (21-69 days). All patients improved promptly on non-steroidal anti-inflammatory drugs without recurrence. Five patients reported negative impact on quality of life and mental health, including 2 cases that led to new vaccine hesitancy, not only to COVID-19 vaccine, but also to other routine vaccines. The rate of cardiac AEFI was estimated for residents of the city of Ottawa and found to be 12.01 cases (CI 90 5.98-21.68) per 100,000 doses following the 2nd dose and 16.56 cases (CI 90 5.66-37.90) per 100,000 doses following the 3rd dose for males aged 12 to 17 years.

CONCLUSIONS

Twelve months following the AEFI, all patients clinically recovered from their myopericarditis, but some reported negative impact on quality of life and mental health, including new vaccine hesitancy. This highlights the importance for timely and systematic evaluation of AEFI and the need to provide support, follow up and vaccine counseling in individuals experiencing an AEFI.

Myocarditis associated with COVID-19 vaccination

Following the start of the COVID-19 vaccination campaign, the adverse events of myocarditis and pericarditis were linked mainly to mRNA COVID-19 vaccines by the regulatory authorities worldwide. COVID-19 vaccines have been administered to several million people and the risk of myocarditis post COVID-19 vaccination has been characterised in great detail. At the present time the research data available are scarce and there is still no clear understanding of the biological mechanism/s responsible for this disease. This manuscript provides a concise overview of the epidemiology of myocarditis and the most prominent mechanistic insights in the pathophysiology of the disease. Most importantly it underscores the needed next steps in the research agenda required to characterize the pathophysiology of this disease post-COVID-19 vaccination. Finally, it shares our perspectives and considerations for public health.

Host genetic variants associated with COVID-19 reconsidered in a Slovak cohort

We present the results of an association study involving hospitalized coronavirus disease 2019 (COVID-19) patients with a clinical background during the 3rd pandemic wave of COVID-19 in Slovakia. Seventeen single nucleotide variants (SNVs) in the eleven most relevant genes, according to the COVID-19 Host Genetics Initiative, were investigated. Our study confirms the validity of the influence of LZTFL1 and 2'-5'-oligoadenylate synthetase (OAS)1/OAS3 genetic variants on the severity of COVID-19. For two LZTFL1 SNVs in complete linkage disequilibrium, rs17713054 and rs73064425, the odds ratios of baseline allelic associations and logistic regressions (LR) adjusted for age and sex ranged in the four tested designs from 2.04 to 2.41 and from 2.05 to 3.98, respectively. The OAS1/OAS3 haplotype 'gttg' carrying a functional allele G of splice-acceptor variant rs10774671 manifested its protective function in the Delta pandemic wave. Significant baseline allelic associations of two DPP9 variants in all tested designs and two IFNAR2 variants in the Omicron pandemic wave were not confirmed by adjusted LR. Nevertheless, adjusted LR showed significant associations of NOTCH4 rs3131294 and TYK2 rs2304256 variants with severity of COVID-19. Hospitalized patients' reported comorbidities were not correlated with genetic variants, except for obesity, smoking (IFNAR2), and hypertension (NOTCH4). The results of our study suggest that host genetic variations have an impact on the severity and duration of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Considering the differences in allelic associations between pandemic waves, they support the hypothesis that every new SARS-CoV-2 variant may modify the host immune response by reconfiguring involved pathways.

Human Genomics of COVID-19 Pneumonia: Contributions of Rare and Common Variants

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection is silent or benign in most infected individuals, but causes hypoxemic COVID-19 pneumonia in about 10% of cases. We review studies of the human genetics of life-threatening COVID-19 pneumonia, focusing on both rare and common variants. Large-scale genome-wide association studies have identified more than 20 common loci robustly associated with COVID-19 pneumonia with modest effect sizes, some implicating genes expressed in the lungs or leukocytes. The most robust association, on chromosome 3, concerns a haplotype inherited from Neanderthals. Sequencing studies focusing on rare variants with a strong effect have been particularly successful, identifying inborn errors of type I interferon (IFN) immunity in 1-5% of unvaccinated patients with critical pneumonia, and their autoimmune phenocopy, autoantibodies against type I IFN, in another 15-20% of cases. Our growing understanding of the impact of human genetic variation on immunity to SARS-CoV-2 is enabling health systems to improve protection for individuals and populations.

Myocarditis and Pericarditis following COVID-19 Vaccination in Thailand

BACKGROUND

Myocarditis and pericarditis cases following Coronavirus 2019 (COVID-19) vaccination were reported worldwide. In Thailand, COVID-19 vaccines were approved for emergency use. Adverse event following immunization (AEFI) surveillance has been strengthened to ensure the safety of the vaccines. This study aimed to describe the characteristics of myocarditis and pericarditis, and identify the factors associated with myocarditis and pericarditis following COVID-19 vaccination in Thailand.

METHOD

We carried out a descriptive study of reports of myocarditis and pericarditis to Thailand's National AEFI Program (AEFI-DDC) between 1 March and 31 December 2021. An unpaired case-control study was conducted to determine the factors associated with myocarditis and pericarditis after the CoronaVac, ChAdOx1-nCoV, BBIBP-CorV, BNT162b2, and mRNA-1273 vaccines. The cases consisted of COVID-19 vaccine recipients who met the definition of confirmed, probable, or suspected cases of myocarditis or pericarditis within 30 days of vaccination. The controls were people who underwent COVID-19 vaccination between 1 March and 31 December 2021, with no adverse reactions documented after vaccination.

RESULTS

Among the 31,125 events recorded in the AEFI-DDC after 104.63 million vaccinations, 204 cases of myocarditis and pericarditis were identified. The majority of them were male (69%). The median age was 15 years (interquartile range (IQR): 13-17). The incidence was highest following the BNT162b2 vaccination (0.97 cases per 100,000 doses administered). Ten deaths were reported in this study; no deaths were reported among children who received the mRNA vaccine. Compared with the age-specific incidence of myocarditis and pericarditis in Thailand before the introduction of the COVID-19 vaccination, the incidence of myocarditis and pericarditis after the BNT162b2 vaccine was greater in the 12-17 and 18-20 age groups in both males and females. It was higher after the second dose in 12- to 17-year-olds (2.68 cases per 100,000 doses administered) and highest after the second dose in male 12- to 17-year-olds (4.43 cases per 100,000 doses administered). Young age and a mRNA-based vaccination were associated with myocarditis and pericarditis following administration of the COVID-19 vaccine after multivariate analysis.

CONCLUSIONS

Myocarditis and pericarditis following vaccination against COVID-19 were uncommon and mild, and were most likely to affect male adolescents. The COVID-19 vaccine offers the recipients enormous benefits. The balance between the risks and advantages of the vaccine and consistent monitoring of AEFI are essential for management of the disease and identification of AEFI.

Race with virus evolution: The development and application of mRNA vaccines against SARS-CoV-2

Since the COVID-19 pandemic was declared, vaccines against SARS-CoV-2 have been urgently developed around the world. On the basis of the mRNA vaccine technology developed previously, COVID-19 mRNA vaccines were promptly tested in animals, advanced to clinical trials, and then authorized for emergency use in humans. The administration of COVID-19 mRNA vaccines has successfully reduced the hospitalization and mortality caused by the viral infection, although the virus continuously evolves with its transmission. Therefore, the development of mRNA vaccine technology, including RNA modification and delivery systems, is well recognized for its contribution to moderating the harms caused by the COVID-19 pandemic. The scientists who developed these technologies, Katalin Karikó, Drew Weissman, and Pieter Cullis, were awarded the 2022 Tang Prize in Biopharmaceutical Science. In this review, we summarize the principles, safety and efficacy of as well as the immune response to COVID-19 mRNA vaccines. Since mRNA vaccine approaches could be practical for the prevention of infectious diseases, we also briefly describe mRNA vaccines against other human viral pathogens in clinical trials.