Estimating Baseline Incidence of Conditions Potentially Associated with Vaccine Adverse Events: a Call for Surveillance System Using the Korean National Health Insurance Claims Data

Real-world safety data for MVA-BN: Increased frequency of syncope following intradermal administration for immunization against mpox disease

BACKGROUND

MVA-BN vaccine (Jynneos, Imvamune, Imvanex) was used widely in the 2022 mpox outbreak. This experience provides real-world evidence about the vaccine's safety, particularly regarding intradermal use.

METHODS

Bavarian Nordic's global safety database was searched for all adverse events following immunization (AEFIs) with MVA-BN. AEFI numbers were compared among administration routes. Selected events and administered doses were graphed over the mpox outbreak period.

RESULTS

A total of 9585 AEFIs have been reported. The rate of myocarditis or pericarditis was <1 per 100,000 doses administered. Eighty-nine cases of syncope, fainting, or loss of consciousness were reported. This number rose after the August 2022 US emergency use authorization for intradermal administration, as did the proportion of all syncope AEFIs reported following intradermal administration (78,7 %).

CONCLUSION

Real-world data from large-scale administration of MVA-BN has confirmed the vaccine's established safety profile when administered subcutaneously. Intradermal administration is likely associated with increased syncopal event frequency.

The incidence of thrombosis with co-occurring thrombocytopenia prior to the SARS-CoV2 pandemic: A population-based study

BACKGROUND

Thrombosis with thrombocytopenia syndrome (TTS) is a very rare prothrombotic disorder that is a safety concern for some COVID-19 vaccines. We aimed to devise a case definition to estimate the incidence of thrombosis with thrombocytopenia as a proxy for TTS in a national insurance claims database.

METHODS

We conducted a retrospective observational study using the National Health Insurance Research Database (NHIRD) in Taiwan over the three-year period prior to the SARS-COV-2 pandemic (2017-2019). Our case definition was all patients with newly diagnosed thrombosis co-occurring with a diagnosis of thrombocytopenia within seven days before or after the thrombosis diagnosis. Cases were identified using International Classification of Disease-10 codes.

FINDINGS

We identified 2010 patients with newly diagnosed thrombosis co-occurring with thrombocytopenia during the study period. The mean age was 64.71 years; female:male ratio 1:1.45. The most frequent thrombotic events were coronary artery disease (18.81%), cerebral infarction (16.87%), and disseminated intravascular coagulation (13.13%). Cerebral venous sinus thrombosis was rare (<0.1%). The average annual incidence rate of co-occurring new diagnoses of thrombosis and thrombocytopenia was 2.84 per 100 000 population. Incidence rates were higher in men than women, except in 20-39 year-olds (higher in females). 20.6% of patients died within the first month after diagnosis.

INTERPRETATION

We observed that the demographic and clinical characteristics of thrombosis with co-occurring thrombocytopenia using our case definition is different from that of TTS. Further research is needed to refine the case definition of TTS in the post-COVID-19 vaccination period.

Comparative safety analysis of mRNA and adenoviral vector COVID-19 vaccines: a nationwide cohort study using an emulated target trial approach

OBJECTIVE

This nationwide cohort study compared the incidence of adverse events of special interest (AESIs) between adenoviral vector-based (ChAdOx1) and mRNA-based (BNT162b2 or mRNA-1273) coronavirus disease 2019 (COVID-19) vaccines.

METHODS

A targeted trial emulation study was conducted using data from the National Health Insurance Service database. Vaccinees aged 18-85 years who had received at least one dose of ChAdOx1 or an mRNA-based vaccine were identified. The 42-day risks of AESIs were calculated.

RESULTS

A total of 1 767 539 ChAdOx1 vaccinees were matched exactly with mRNA vaccinees according to their risk factors. The 42-day risks of adverse events were low (∼0 to 176 events per 100 000 persons in both vaccine groups), and the incidence rates of AESIs were comparable between the two platforms, except for a higher occurrence of acute cardiac injury (incidence rate ratio [IRR], 1.22; 95% CI, 1.10-1.35), myocarditis or pericarditis (IRR, 2.14; 95% CI, 1.14-4.04), and arrhythmia (IRR, 1.46; 95% CI, 1.24-1.71) in mRNA vaccinees. The incidence of Guillain-Barré syndrome (IRR, 0.20; 95% CI, 0.06-0.69), vasovagal syncope (IRR, 0.77; 95% CI, 0.62-0.97), radiculopathy (IRR = 0.59, 95% CI, 0.41-0.84), and aseptic arthritis (IRR, 0.81; 95% CI, 0.70-0.93) was significantly lower in mRNA-based vaccinees compared with ChAdOx1 vaccinees.

DISCUSSION

A remarkable platform-dependent difference was observed in the safety profiles of COVID-19 vaccines, particularly for myocarditis or pericarditis and Guillain-Barré syndrome. However, the overall risk of AESIs was low for both vaccine platforms.

COVID-19 vaccines breakthrough infection and adverse reactions in medical students: a nationwide survey in Iran

Introduction

There are different types of COVID-19 vaccines approved worldwide. Since no national studies focus on vaccine-related adverse reactions and breakthrough cases, this study aimed to investigate the rate of adverse events and COVID-19 infection in medical students in Iran.

Methods

This retrospective cohort study included Iranian medical students who received two doses of COVID-19 vaccines. The medical team gathered the demographic characteristics, comorbidities, type of vaccine, adverse events following vaccination, and history of COVID-19 infection data through a phone interview. The frequency of adverse events and breakthrough infection was stratified by vaccine type (ChAdOx1-S, Gam-COVID-Vac, and BIBP-CorV).

Results

A total of 3,591 medical students enrolled in this study, of which 57.02% were females, with a mean age of 23.31 + 4.87. A PCR-confirmed and suspicious-for-COVID-19 breakthrough infection rate of 4.51 and 7.02% was detected, respectively. There was no significant relation between breakthrough infection and gender, BMI, blood groups, and comorbidities. However, there was a significant difference in breakthrough infection rate among different types of vaccines (p = 0.001) and history of COVID-19 infection (p = 0.001). A total of 16 participants were hospitalized due to COVID-19 infection after vaccination for reasons such as dyspnea, abnormal imaging, or decreased oxygen saturation. No severe infection or death was observed in the studied population.

Conclusion

Vaccination prevented severe COVID-19 infection, although a high breakthrough infection rate was evident among Iranian medical students during the Delta variant's peak. Vaccine effectiveness may be fragile during emerging new variants and in high-exposure settings. Moreover, adverse events are rare, and the benefits of vaccination outweigh the side effects. However, many limitations challenged this study, and the results should be cautious.

Short-term Side Effects of COVID-19 Vaccines (Astrazeneca, Sputnik-V, and Sinopharm) in Health Care Workers: A Cross-Sectional Study in Iran

Background: The occurrence of side effects of vaccines plays an important role in their acceptance by people. Therefore, the aim of this study was to evaluate the side effects of COVID-19 vaccines (Sputnik-V, AstraZeneca, and Sinopharm) in Neyshabur health care workers (HCWs). Methods: A cross-sectional study was performed to evaluate the side effects of COVID-19 vaccines among the HCWs of the Neyshabur University of Medical Sciences from July 31, 2021, to September 6, 2021, by using a self-report checklist. We sent our checklist via an internet link to collect data such as demographic data of participants, previous COVID-19 infection (PCR+), vaccine information and side effects of vaccines. Mean, median and standard deviation were used to determine descriptive statistics and a logistic regression model was also used to determine the relationship between the type of vaccine and its side effects. Results: 317 participants filled out the checklist; among them 47% (N= 149), 21.14% (N= 67), and 31.86% (N= 101) have been vaccinated with Sputnik-V, AstraZeneca, and Sinopharm, respectively. The percentage of side effects after the first dose was 62.15% (N= 197). The Percentage of local side effects was 76% (N= 241) and systemic side effects were 29.36% (N= 95). The most common side effects in all three vaccines were injection site pain (75.08%, N= 240), muscle pain (62.46%, N=198) and headache (52.05%, N=165). Also, the odds ratio of injection site pain, chill and sweating in those who received the AstraZeneca vaccine was 3.9(95% CI, 1.7-9.3), 3.7 (95% CI, 1.8-7.3), and 3.2 (95% CI, 1.7-63), of those who received the Sputnik V vaccine (p ≤ 0.001). Conclusion: The most common side effects among our participants were injection site pain, muscle pain, and headache. Most of the post-vaccination side effects are mild to moderate in severity and self-limited. Reported side effects were more common in recipients with AstraZeneca than in those with Sputnik-V and Sinopharm.

A case report of possible concurrent vasculitis in vertebral bodies and partial transverse myelitis following COVID-19 vaccination

INTRODUCTION

Cases with organ-specific and systemic vasculitis associated with corona virus disease 2019 (COVID-19) vaccination have been reported. However, acute partial transverse myelitis (APTM) is rare adverse events following received COVID-19 vaccines. To the best of our knowledge, there is no report on vaccine-associated APTM accompanied by possible concurrent vasculitis. Herein we present a case with possible concurrent spinal vasculitis and APTM following the second dose of inactivated COVID-19 vaccine.

CASE SUMMARY

A 33-year-old man presented with weakness of left lower limb and aberrant sensation of his left lower trunk and limb (from T9 level to toes) for 2 days following receipt of an inactivated COVID-19 vaccine. Remarkable demyelinating lesion at T7 spinal cord was showed by 3.0T magnetic resonance imaging (MRI) scan. Moreover, vertebral bodies of T3-T7 also presented high signal in T-2 weighted imaging (T2WI) accompanied by multiple sites of flowing void effect indicating possible vasculitis. Oligoclonal band was positive in cerebrospinal fluid (CSF) while it was negative in sera. Intravenous methylprednisolone (1 g/d) was administrated for 5 days followed by subsequent dose-tapering prednisone. His limb weakness and aberrant sensation both improved and he was able to walk unaided after treatment. The MRI recheck also showed remarkable improvement on the lesions in spinal cord and vertebral bodies.

CONCLUSION

this case illustrates the concurrence of possible vasculitis in vertebral bodies and acute transverse myelitis (ATM) following COVID-19 vaccination.

Detection of Short-Term Side Effects of ChAdOx1 nCoV-19 Vaccine: A Cross-Sectional Study in a War-Torn Country

Purpose

The chAdOx1 nCoV-19 vaccine is the first COVID-19 vaccine available in Yemen. Hence, this local-based study was used to identify the type and frequency of short-term side effects following 48 hours of the first shot of the vaccine.

Methods

A cross-section of vaccinated participants in Aden were surveyed by telephone. Descriptive statistics were used for statistical analysis.

Results

A total of 500 participants were included through convenient sampling. 27% of them were health care providers. Nearly 70% of the respondent experienced side effects. The top three side effects reported were fever (n=276, 55.2%), myalgia (n=270, 54%) and fatigue (n=247, 49.4%). Generally, most participants stated that they experienced the side effects after the first 24 hours of vaccination.

Conclusion

Side effects that participants experienced were not different from the literature, indicating a safe profile for the vaccine. Further studies are needed to identify the side effects after the second and third dose of the vaccine. In addition, more studies are required to assess the efficacy of the existing vaccines against new variants.

Delayed Vasovagal Reaction with Reflex Syncope Following COVID-19 Vaccination

Coronavirus disease 2019 (COVID-19) has become a pandemic, and vaccines remain the only effective tools available for ending it. However, their side effects, such as syncope, which mimics sudden cardiac death, are serious concerns. We herein report 6 cases of delayed vasovagal syncope and presyncope (VVR) caused by COVID-19 vaccination among 25,530 COVID-19 patients. The prevalence of delayed VVR due to COVID-19 vaccination was 0.026%. In addition, no delayed VVR was found among 17,386 patients who received the influenza vaccine. Delayed VVR is likely to be overlooked if medical staff are not aware of this symptom. This report provides significant information regarding effects of COVID-19 vaccination.

Incidence, Pattern and Severity of Adverse Events Following Immunization (AEFIs) Associated With Chadox1 nCOV-19 Corona Virus Vaccine (Recombinant) Among the Healthcare Workers of a Tertiary Care Institute of Eastern Uttar Pradesh, India

Background

In January 2020, the Government of India based on the recommendation of the Drugs Controller General of India (DCGI) and National Technical Advisory Group on Immunization (NTAGI) started the rollout of the COVID-19 vaccine in the country. Two vaccines, ChAdOx1 nCoV-19 coronavirus vaccine (recombinant), i.e., COVISHIELD produced by Serum Institute of India and COVAXIN developed indigenously by Bharat Biotech, were given emergency use authorisation (EUA) by the DCGI.

Methods

In this cohort study, we assessed the incidence, pattern and severity of adverse events following immunization (AEFI) observed among the healthcare workers of a large tertiary care institute in eastern U.P., India vaccinated with ChAdOx1 nCoV-19 Coronavirus vaccine (recombinant) within 30 minutes of vaccination by direct observation.

Results

Out of the total 836 healthcare workers who were vaccinated with the first dose of the vaccine, around 10% experienced any AEFI within the directly observed period. The most common AEFI was pain/tenderness at the injection site experienced by 59.3% of those who experienced any AEFI followed by headache/dizziness (35.3%), itching/rashes at the injection site (8.1%), nausea/vomiting (5.8%) and fever/chills (4.7%). The majority (95.3%) of the AEFIs observed were of minor severity with no serious AEFIs observed as per the WHO severity classification.

Conclusion

ChAdOx1 nCoV-19 Coronavirus vaccine (recombinant) is proven to be safe based on our findings as the majority of AEFIs observed were of minor grade only. However, the vaccine beneficiaries should be strictly observed for a minimum of 30 minutes at the vaccination site to look for any serious AEFI with arrangements to manage the same.

Adverse Effects of the COVID-19 Vaccine Reported by Lecturers and Staff of Kabul University of Medical Sciences, Kabul, Afghanistan

Purpose

To evaluate the occurrence, extent, and severity of adverse reactions associated with the vaccine of COVID-19 (ChAdOx1 nCoV-19 vaccine or AstraZeneca) among Kabul University of Medical Sciences staff.

Patients and Methods

A retrospective observational, interview-based study was conducted from 4 to 20 April, 2021, to evaluate the adverse reactions associated with the vaccine of COVID-19 (ChAdOx1 nCoV-19 vaccine or AstraZeneca) among the staff and lecturers of the Kabul University of Medical Sciences, Kabul, Afghanistan. Participants were interviewed following the administration of the first dose of the AstraZeneca vaccines. They were asked to report any adverse reactions that occurred within 8–10 days after vaccination. The frequency, duration, severity, and outcome of the reactions were recorded. Association of the adverse reactions was analysed with the ages of participants and previous infection with SARS CoV-2.

Results

The most common adverse reactions reported by the participants were muscle pain (68.3%), local pain (58.8%) at the site of injection (68.3%), fever (66.3%) and fatigue (66.3%). Almost half of the respondents reported chills, joint pain and headache after receiving the first shot of the vaccine. The frequency of adverse reactions was higher in participants aged 40 years or less, and in those previously infected with SARS CoV-2. The severity of most adverse reactions was mild to moderate. No serious case or death was reported.

Conclusion

The adverse reactions reported by the participants were mild to moderate in severity, and for a short duration. The findings of this study help us to address the vaccine hesitancy caused by worries about severe adverse effects associated with the COVID-19 vaccine.

Anaphylaxis and digital medicine

PURPOSE OF REVIEW

Digital medicine (mHealth) aims to help patients and healthcare providers (HCPs) improve and facilitate the provision of patient care. It encompasses equipment/connected medical devices, mHealth services and mHealth apps (apps). An updated review on digital health in anaphylaxis is proposed.

RECENT FINDINGS

In anaphylaxis, mHealth is used in electronic health records and registries.It will greatly benefit from the new International Classification of Diseases-11 rules and artificial intelligence. Telehealth has been revolutionised by the coronavirus disease 2019 pandemic, and lessons learnt should be extended to shared decision making in anaphylaxis. Very few nonvalidated apps exist and there is an urgent need to develop and validate such tools.

SUMMARY

Although digital health appears to be of great importance in anaphylaxis, it is still insufficiently used.

Machine Learning Approach for Active Vaccine Safety Monitoring

BACKGROUND

Vaccine safety surveillance is important because it is related to vaccine hesitancy, which affects vaccination rate. To increase confidence in vaccination, the active monitoring of vaccine adverse events is important. For effective active surveillance, we developed and verified a machine learning-based active surveillance system using national claim data.

METHODS

We used two databases, one from the Korea Disease Control and Prevention Agency, which contains flu vaccination records for the elderly, and another from the National Health Insurance Service, which contains the claim data of vaccinated people. We developed a case-crossover design based machine learning model to predict the health outcome of interest events (anaphylaxis and agranulocytosis) using a random forest. Feature importance values were evaluated to determine candidate associations with each outcome. We investigated the relationship of the features to each event via a literature review, comparison with the Side Effect Resource, and using the Local Interpretable Model-agnostic Explanation method.

RESULTS

The trained model predicted each health outcome of interest with a high accuracy (approximately 70%). We found literature supporting our results, and most of the important drug-related features were listed in the Side Effect Resource database as inducing the health outcome of interest. For anaphylaxis, flu vaccination ranked high in our feature importance analysis and had a positive association in Local Interpretable Model-Agnostic Explanation analysis. Although the feature importance of vaccination was lower for agranulocytosis, it also had a positive relationship in the Local Interpretable Model-Agnostic Explanation analysis.

CONCLUSION

We developed a machine learning-based active surveillance system for detecting possible factors that can induce adverse events using health claim and vaccination databases. The results of the study demonstrated a potentially useful application of two linked national health record databases. Our model can contribute to the establishment of a system for conducting active surveillance on vaccination.

Predicted and Observed Incidence of Thromboembolic Events among Koreans Vaccinated with ChAdOx1 nCoV-19 Vaccine

We used the nationwide claims database to calculate the incidence of thrombotic events and predict their overall 2-week incidence. From 2006 to 2020, the incidence of deep vein thrombosis (DVT), pulmonary embolism (PE), and disseminated intravascular coagulation (DIC) tended to increase. Unlike intracranial venous thrombosis (ICVT) and intracranial thrombophlebitis (ICTP), which showed no age difference, other venous embolism, and thrombosis (OVET), DIC, DVT, and PE were significantly more common in over 65 years. The overall 2-week incidence of ICVT was 0.21/1,000,000 (95% confidence interval [CI], 0.11-0.32). ICTP, OVET, DIC, DVT and PE were expected to occur in 0.08 (95% CI, 0.02-0.14), 7.66 (95% CI, 6.08-9.23), 5.95 (95% CI, 4.88-7.03), 13.28 (95% CI, 11.92-14.64), 14.09 (95% CI, 12.80-15.37) per 1,000,000, respectively. To date, of 8,548,231 patients vaccinated with ChAdOx1 nCoV-19 in Korea, two had confirmed thrombosis with thrombocytopenia syndrome within 2 weeks. The observed incidence of ICVT after vaccination was 0.23/1,000,000.

Adverse Events Following Immunization Associated with Coronavirus Disease 2019 Vaccination Reported in the Mobile Vaccine Adverse Events Reporting System

BACKGROUND

Vaccination against coronavirus disease 2019 (COVID-19) is underway globally to prevent the infection caused by the severe acute respiratory syndrome coronavirus 2. We aimed to investigate the adverse events following immunization (AEFIs) for COVID-19 among healthcare workers (HCWs).

METHODS

This was a retrospective study of the AEFIs associated with the first dose of the ChAdOx1 nCoV-19 vaccine at the Kosin University Gospel Hospital from March 3 to March 22, 2021. We investigated the systemic and local adverse events during the 7 days following the vaccination using the Mobile Vaccine Adverse Events Reporting System (MVAERS) developed by our hospital.

RESULTS

A total of 1,503 HCWs were vaccinated, and the data of 994 HCWs were reported in the MVAERS. The most commonly reported AEFIs were tenderness at the injection site (94.5%), fatigue (92.9%), pain at the injection site (88.0%), and malaise (83.8%). The severity of most AEFIs was mild-to-moderate, and the severity and number of AEFIs were less in the older age group. There were no serious events requiring hospitalization, and most AEFIs improved within a few days.

CONCLUSION

The AEFIs associated with the ChAdOx1 nCoV-19 vaccine were tolerable, and the use of the MVAERS was helpful in monitoring the AEFIs. The use of MVAERS will help in sharing accurate and ample information about vaccination against COVID-19.

COVID-19 Vaccine-associated Anaphylaxis and Allergic Reactions: Consensus Statements of the KAAACI Urticaria/Angioedema/Anaphylaxis Working Group

In the era of novel coronavirus epidemics, vaccines against coronavirus disease 2019 (COVID-19) have been recognized as the most effective public health interventions to control the pandemic. An adverse event following immunization (AEFI) is defined as any untoward occurrence following immunization, and the majority of AEFIs are caused by protective immune responses stimulated by vaccines. Most of the reported AEFIs are not serious, and many are not immunologically mediated or even reproducible on re-exposure. However, uncommon severe allergic adverse reactions, such as anaphylaxis or other allergic reactions, can occur after vaccinations. Confirmed allergic reactions to vaccines may be caused by residual non-human protein, preservatives, or stabilizers in the vaccine formulation (also known as excipients). There are 2 main potential allergenic/immunogenic excipients in COVID-19 vaccines, polyethylene glycol (PEG) and polysorbate 80. PEG, also known as macrogol, is an ingredient in various laxatives and injectable formulations, such as depot steroids. Polysorbate 80 is present in various medical products, creams, ointments, lotions, and medication tablets. Contraindications to the administration of COVID-19 vaccines include a previous history of severe allergic reactions to the first dose of COVID-19 vaccine or proven hypersensitivity to a vaccine component, such as PEG or polysorbate 80. Anaphylaxis or other allergic reactions following immunization can cause fear and loss of confidence in the safety of vaccines among the public. A better understanding of these events is thought to help alleviate concerns about the current COVID-19 vaccines and provide reassurance to the general population by analyzing the exact incidence of anaphylaxis and potential risk factors. COVID-19 vaccine-associated anaphylaxis could be prevented and managed by risk stratification based on our local and global experience.