Incidence of myopericarditis after mRNA COVID-19 vaccination: A meta-analysis with focus on adolescents aged 12–17 years

BackgroundThe incidence of myopericarditis after mRNA COVID-19 vaccination among adolescents aged 12–17 years remains unknown. Therefore, we conducted a study to pool the incidence of myopericarditis following COVID-19 vaccination in this age group.MethodsWe did a meta-analysis by searching 4 electronic databases until February 6, 2023. The following main keywords were used: “COVID-19”, “vaccines”, “myocarditis”, “pericarditis”, and “myopericarditis”. Observational studies reporting on adolescents aged 12–17 years who had myopericarditis in temporal relation to receiving mRNA COVID-19 vaccines were included. The pooled incidence of myopericarditis and 95 % confidence interval (CI) were calculated using a single-group meta-analysis.ResultsFifteen studies were included. The pooled incidences of myopericarditis after mRNA COVID-19 vaccination among adolescents aged 12–17 years were 43.5 (95 % CI, 30.8–61.6) cases per million vaccine doses for both BNT162b2 and mRNA-1273 (39 628 242 doses; 14 studies), and 41.8 (29.4–59.4) cases for BNT162b2 alone (38 756 553 doses; 13 studies). Myopericarditis was more common among males (66.0 [40.5–107.7] cases) than females (10.1 [6.0–17.0] cases) and among those receiving the second dose (60.4 [37.6–96.9] cases) than those receiving the first dose (16.6 [8.7–31.9] cases). The incidences of myopericarditis did not differ significantly when grouped by age, type of myopericarditis, country, and World Health Organization region. None of the incidences of myopericarditis pooled in the current study were higher than those after smallpox vaccinations and non-COVID-19 vaccinations, and all of them were significantly lower than those in adolescents aged 12–17 years after COVID-19 infection.ConclusionsThe incidences of myopericarditis after mRNA COVID-19 vaccination among adolescents aged 12–17 years were very rare; they were not higher than other important reference incidences. These findings provide an important context for health policy makers and parents with vaccination hesitancy to weight the risks and benefits of mRNA COVID-19 vaccination among adolescents aged 12–17 years.     

COVID-19 vaccination coverage in patients with chronic obstructive pulmonary disease – A cross-sectional study in Hungary

IntroductionCoronavirus infection is a particular risk for patients with chronic obstructive pulmonary disease (COPD), because they are much more likely to become severely ill due to oxygen supply problems. Primary prevention, including COVID-19 vaccination is of paramount importance in this disease group. The aim of our study was to assess COVID-19 vaccination coverage in COPD patients during the first vaccination campaign of the COVID-19 pandemic.MethodsA cross-sectional observational study (CHANCE) has been conducted in COPD patients in the eastern, western and central regions of Hungary from 15th November 2021. The anthropometric, respiratory function test results and vaccination status of 1,511 randomly selected patients were recorded who were aged 35 years and older.ResultsThe median age was 67 (61–72) years, for men: 67 (62–73) and for women: 66 (60–72) years, with 47.98 % men and 52.02 % women in our sample. The prevalence of vaccination coverage for the first COVID-19 vaccine dose was 88.62 %, whereas 86.57 % of the patients received the second vaccine dose. When unvaccinated (n = 172) and double vaccinated (n = 1308) patients were compared, the difference was significant both in quality of life (CAT: 17 (12–23) vs 14 (10–19); p < 0.001) and severity of dyspnea (mMRC: 2 (2–2) vs 2 (1–2); p = 0.048). The COVID-19 infection rate between double vaccinated and unvaccinated patients was 1.61 % vs 22.67 %; p < 0.001 six months after vaccination. The difference between unvaccinated and vaccinated patients was significant (8.14 % vs 0.08 %; p < 0.001) among those with acute COVID-19 infection hospitalized. In terms of post-COVID symptoms, single or double vaccinated patients had significantly fewer outpatient hospital admissions than unvaccinated patients (7.56 vs 0 %; p < 0.001).ConclusionThe COVID-19 vaccination coverage was satisfactory in our sample. The uptake of COVID-19 vaccines by patients with COPD is of utmost importance because they are much more likely to develop severe complications.     

Acute reactions after a homologous primary COVID-19 vaccination series: Analysis of Taiwan V-Watch data

IntroductionThe ChAdOx1 nCoV-19 (ChAd), mRNA-1273 (m1273), MVC-COV1901 (MVC), and BNT162b2 (BNT) COVID-19 vaccines received authorization for emergency use in Taiwan beginning in February 2021. We investigated acute reactions to homologous primary COVID-19 vaccination series in adults aged ≥ 18 years.MethodsIn this prospective observational study based on smartphone data (Taiwan V-Watch), we calculated the frequencies of self-reported local and systemic acute reactions within 7 days of a COVID-19 vaccination, and the health effects up to 3 weeks after each dose. Those who reported adverse reactions after both doses were assessed by the McNemar test.ResultsDuring 22 March 2021–13 December 2021, 77,468 adults were enrolled; 59.0 % were female and 77.8 % were aged 18–49 years. For both doses of all four vaccines, the local and systemic reactions were minor in severity and highest on days 1 and 2 after vaccination, and declined markedly until day 7. For 65,367 participants who provided data after the first and second doses, systemic reactions were more frequent after dose 2 of the BNT and m1273 vaccines (McNemar tests: both p < 0.001), while local reactions were more frequent after dose 2 of the m1273 and MVC vaccines (both p < 0.001), compared with dose 1 of the homologous vaccine. Among the participants aged 18–49 years, the percentage who missed work on the day after vaccination was slightly higher among women (9.3 %) than among men (7.0 %).ConclusionsAcute reactogenicity and impact of work absenteeism for the four COVID vaccines in the V-Watch survey were mild and of short duration.     

Evaluation of mortality risk after COVID-19 vaccination,Utah 2021

IntroductionIn order to evaluate trends in death after COVID-19 vaccination we analyzed the timing of death relative to vaccination date and the causes of death in vaccinated Utahns in 2021.MethodsWe matched people in the Utah immunization registry with documented COVID-19 vaccinations between December 18, 2020 and December 31, 2021 to Utah’s 2021 vital statistics death records. Vaccinated people were categorized as having one, two, or ≥ three COVID-19 vaccine doses in a time-updated metric. We examined crude mortality rates by dosing groups in two-week intervals for all deaths, and by COVID-19 versus non-COVID-19 causes, within the 44 weeks following receipt of the most recent vaccine.ResultsWe identified 2,072,908 individuals who received at least one dose of COVID-19 vaccine of whom 10,997 died in 2021. Only 17.5 % of the total vaccinated population was age 65+, while 80.9 % of those who died were over 65. In the four weeks following the first or second vaccination, all-cause mortality was low and then stabilized for the remainder of the evaluation period at a bi-weekly average of 33.0 and 39.0 deaths/100,000 people for one and two doses, respectively. Typical seasonal variation in death was observed among those with two doses. Small sample size precluded analysis of those with ≥ three doses, but trends were similar.ConclusionsMortality rates in the 44 weeks following the COVID-19 vaccination did not show trends suggesting an increase in mortality related to COVID-19 vaccination, reinforcing the safety of COVID-19 vaccines. This represents an accessible approach for local evaluation.     

A case-crossover study of the effect of vaccination on SARS-CoV-2 transmission relevant behaviours during a period of national lockdown in England and Wales

BackgroundStudies of COVID-19 vaccine effectiveness show increases in COVID-19 cases within 14 days of a first dose, potentially reflecting post-vaccination behaviour changes associated with SARS-CoV-2 transmission before vaccine protection. However, direct evidence for a relationship between vaccination and behaviour is lacking. We aimed to examine the association between vaccination status and self-reported non-household contacts and non-essential activities during a national lockdown in England and Wales.MethodsParticipants (n = 1154) who had received the first dose of a COVID-19 vaccine reported non-household contacts and non-essential activities from February to March 2021 in monthly surveys during a national lockdown in England and Wales. We used a case-crossover study design and conditional logistic regression to examine the association between vaccination status (pre-vaccination vs 14 days post-vaccination) and self-reported contacts and activities within individuals. Stratified subgroup analyses examined potential effect heterogeneity by sociodemographic characteristics such as sex, household income or age group.Results457/1154 (39.60 %) participants reported non-household contacts post-vaccination compared with 371/1154 (32.15 %) participants pre-vaccination. 100/1154 (8.67 %) participants reported use of non-essential shops or services post-vaccination compared with 74/1154 (6.41 %) participants pre-vaccination. Post-vaccination status was associated with increased odds of reporting non-household contacts (OR 1.65, 95 % CI 1.31–2.06, p < 0.001) and use of non-essential shops or services (OR 1.50, 95 % CI 1.03–2.17, p = 0.032). This effect varied between men and women and different age groups.ConclusionParticipants had higher odds of reporting non-household contacts and use of non-essential shops or services within 14 days of their first COVID-19 vaccine compared to pre-vaccination. Public health emphasis on maintaining protective behaviours during this post-vaccination time period when individuals have yet to develop full protection from vaccination could reduce risk of SARS-CoV-2 infection.     

Antibody titers among healthcare workers for coronavirus disease 2019 at 6 months after BNT162b2 vaccination

BackgroundAntibody levels decrease substantially at 6 months after the BNT162b2 vaccine. The factors influencing titer of antibodies against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) among healthcare workers for coronavirus disease 2019 (COVID-19) is unclear.MethodsWe conducted a 6-month longitudinal prospective study in Japanese healthcare workers in a tertiary care hospital for COVID-19. Participants in the study were tested for the presence of anti-spike protein (SP) IgG antibodies before and at 1 and 6 months after the last vaccination dose.ResultsAmong 1076 healthcare workers, 794 received the vaccine, and 469 entered the study. Five were infected with SARS-CoV-2 (none among COVID-19 section workers) by the end of the study and 451 participants were finally analyzed (mean age, 42.5 years; 27.3 % male; 18.8 % COVID-19 section workers). Median SP IgG index values were 0.0, 44.4, and 5.5 before and at 1 and 6 months after the last dose, respectively. Regression analysis revealed a negative correlation of SP IgG antibody levels with age (P < 0.0001), and higher levels in COVID-19 section workers (P = 0.0185) and in females (P = 0.0201).ConclusionIn healthcare workers at a COVID-19 hospital, IgG antibody titer was substantially lower at 6 months after receipt of the last dose of the BNT162b2 vaccine compared with that 1 month after the last dose, but was better preserved among younger participants, COVID-19 section workers and females.     

COVID-19 booster vaccination during pregnancy enhances maternal binding and neutralizing antibody responses and transplacental antibody transfer to the newborn

The immune response to COVID-19 booster vaccinations during pregnancy for mothers and their newborns and the functional response of vaccine-induced antibodies against Omicron variants are not well characterized. We conducted a prospective, multicenter cohort study of participants vaccinated during pregnancy with primary or booster mRNA COVID-19 vaccines from July 2021 to January 2022 at 9 academic sites. We determined SARS-CoV-2 binding and live virus and pseudovirus neutralizing antibody (nAb) titers pre- and post-vaccination, and at delivery for both maternal and infant participants. Immune responses to ancestral and Omicron BA.1 SARS-CoV-2 strains were compared between primary and booster vaccine recipients in maternal sera at delivery and in cord blood, after adjusting for days since last vaccination.A total of 240 participants received either Pfizer or Moderna mRNA vaccine during pregnancy (primary 2-dose series: 167; booster dose: 73). Booster vaccination resulted in significantly higher binding and nAb titers, including to the Omicron BA.1 variant, in maternal serum at delivery and in cord blood compared to a primary 2-dose series (range 0.44–0.88 log₁₀ higher, p < 0.0001 for all comparisons). Live virus nAb to Omicron BA.1 were present at delivery in 9 % (GMT ID50 12.7) of Pfizer and 22 % (GMT ID50 14.7) of Moderna primary series recipients, and in 73 % (GMT ID50 60.2) of mRNA boosted participants (p < 0.0001), although titers were significantly lower than to the D614G strain. Transplacental antibody transfer was efficient for all regimens with median transfer ratio range: 1.55–1.77 for IgG, 1.00–1.78 for live virus nAb and 1.79–2.36 for pseudovirus nAb. COVID-19 mRNA vaccination during pregnancy elicited robust immune responses in mothers and efficient transplacental antibody transfer to the newborn. A booster dose during pregnancy significantly increased maternal and cord blood binding and neutralizing antibody levels, including against Omicron BA.1. Findings support the use of a booster dose of COVID-19 vaccine during pregnancy.     

Frequency and temporal evolution of COVID-19 vaccination rate among oncological patients undergoing 18F-FDG-PET

PurposeTo evaluate the temporal evolution of vaccination against COVID-19 in a Swiss oncological cohort.MethodsHistory of complete vaccination (i.e. at least two vaccine doses) against COVID-19 of patients undergoing oncological 18F-FDG PET/CT between February and September 2021 (n = 2613) was taken. Vaccination rate was compared with age-matched national data from the Swiss Federal Office of Public Health. Subgroup differences in temporal evolution of vaccination rate were analyzed by fitting a generalized linear model and determined by significant interaction between, sex, oncological diagnosis, and month of examination.ResultsRate of complete vaccination against COVID-19 steadily increased and reached 81 % in September 2021. The fraction of vaccinated patients in the oncological cohort was higher in the beginning and approached the fraction in the age-matched general Swiss population at the end of the study period. Month of exam (p < 0.001) was the only significant predictor of the vaccination rate.ConclusionVaccination rate against COVID-19 in a Swiss oncological cohort increased steadily from February to September 2021. Compared to the age-matched general population it was higher in the beginning and similar by the end of the study period.Ethics approval: Trial registration: BASEC 2021-00444, Ethikkommission Zürich (Cantonal Ethics Committee Zurich), Switzerland, registered February 24th 2021.     

Vasovagal reactions after COVID-19 vaccination in Japan

Coronavirus disease 2019 (COVID-19) vaccine administration started in February 2021 in Japan. As of December 2021, approximately 75% of the population aged ≥12 years had received two doses of vaccine. We conducted a study to investigate vasovagal reactions (VVR) after COVID-19 vaccination using data on adverse events following immunization. The crude reporting rate of VVR (cases/1,000,000 doses) after vaccination was 9.6 in all age groups combined, and was more frequent in the younger age groups: 28.6 and 37.2 in individuals aged 10–19 years and 20–29 years, respectively. In individuals aged 10–29 years, the rate was similar in males and females (33.0 and 34.2, respectively, p = 0.53); but was higher after dose 1 than after dose 2 (57.4 and 8.8, respectively, p < 0.001). Based on these results, caution needs to be exercised when vaccinating adolescents and young adults, especially with dose 1 of COVID-19 vaccines.     

Protection of vaccination versus hybrid immunity against infection with COVID-19 Omicron variants among Health-Care Workers

Background aimThe Omicron COVID-19 variants BA.1* and BA.2* evade immune system leading to increased transmissibility and breakthrough infections. We aim to test the hypothesis that immunity achieved post COVID-19 infection combined with vaccination (hybrid immunity), is more effective against Omicron infection than vaccination alone in a health-care setting.MethodsData on regular pre-emptive PCR testing from all Health-Care Workers (HCWs) at Laiko University Hospital from 29th December 2020, date on which the national COVID-19 immunization program began in Greece, until 24th May 2022, were retrospectively collected and recorded. The infection rate was calculated after December 21st, 2021, when Omicron was the predominant circulating variant in Greece, as the total number of infections (positive PCR COVID-19 test regardless of symptoms) divided by the total person-months at risk.ResultsOf 1,305 vaccinated HCWs who were included in the analysis [median age of 47 (IQR: 36, 56) years, 66.7 % women], 13 % and 87 % had received 2 or 3 vaccine doses (full and booster vaccination), respectively. A COVID-19 infection had occurred in 135 of 1,305 of participants prior to Omicron predominance. Of those 135 HCWs with hybrid immunity only 13 (9.6 %) were re-infected. Of the 154 and 1,016 HCWs with full and booster vaccination-induced immunity, respectively, 71 (46.1 %, infection rate 13.4/100 person-months) and 448 (44.1 %, infection rate 12.2/100 person-months) were infected during the follow up period. No association between gender or age and COVID-19 infection was found and none of the participants had a severe infection or died.ConclusionsHybrid immunity confers higher protection by almost 5-fold compared to full or booster vaccination for COVID-19 infection with the Omicron variant among HCWs who are at high risk of exposure. This may inform public health policies on how to achieve optimal immunity in terms of the timing and mode of vaccination.     

Reactions following Pfizer-BioNTech COVID-19 mRNA vaccination and related healthcare encounters among 7,077 children aged 5-11 years within an integrated healthcare system

BackgroundStudies combining data from digital surveys and electronic health records (EHR) can be used to conduct comprehensive assessments on COVID-19 vaccine safety.MethodsWe conducted an observational study using data from a digital survey and EHR of children aged 5–11 years vaccinated with Pfizer-BioNTech COVID-19 mRNA vaccine across Kaiser Permanente Southern California during November 4, 2021-February 28, 2022. Parents/guardians who enrolled their children were sent a 14-day survey on reactions. Survey results were combined with EHR, and medical encounters were described for children whose parents or guardians indicated seeking medical care for vaccine-related symptoms. This study describes self-reported reactions (local and systemic) and additional symptoms (chest pain, tachycardia, and pre-syncope).ResultsThe study recruited 7,077 participants aged 5–11 years who received the Pfizer-BioNTech COVID-19 mRNA vaccine. Of 6,247 participants with survey responses after dose 1, 2,176 (35 %) reported at least one systemic reaction, and 1,076 (32 %) of 3,401 respondents following dose 2 reported at least one systemic reaction. Local reactions were reported less frequently following dose 2 (1,113, 33 %) than dose 1 (3,140, 50 %). The most frequently reported reactions after dose 1 were pain at the injection site (48 %), fatigue (20 %), headache (12 %), myalgia (9 %) and fever (5 %). The most frequently reported symptoms after dose 2 were also pain at the injection site (30 %), fatigue (19 %), headache (13 %), myalgia (10 %) and fever (9 %). Post-vaccination reactions occurred most frequently-one day following vaccination. Chest pain or tachycardia were reported infrequently (1 %). EHR demonstrated that parents rarely sought care for post-vaccination symptoms, and among those seeking care, the most common symptoms documented in EHR were fever and nausea, comprising <0.5 % of children. No encounters were related to myocarditis.ConclusionWhile post-vaccination reactions to the Pfizer-BioNTech COVID-19 mRNA vaccine were common in children aged 5–11 years, our data showed that in most cases they were transient and did not require medical care.     

Intention of nurses to accept coronavirus disease 2019 vaccination and change of intention to accept seasonal influenza vaccination during the coronavirus disease 2019 pandemic: A cross-sectional survey

BackgroundMaintaining health of healthcare workers with vaccination is a major component of pandemic preparedness and acceptance of vaccinations is essential to its success. This study aimed to examine impact of the coronavirus disease 2019 (COVID-19) pandemic on change of influenza vaccination acceptance and identify factors associated with acceptance of potential COVID-19 vaccination.MethodA cross-sectional self-administered anonymous questionnaire survey was conducted among nurses in Hong Kong, China during 26 February and 31 March 2020. Their previous acceptance of influenza vaccination and intentions to accept influenza and COVID-19 vaccination were collected. Their relationship with work-related and other factors were examined using multiple multinomial logistic regressions.ResultsResponses from 806 participants were retrieved. More nurses changed from vaccination refusal to hesitancy or acceptance than those changed from acceptance to vaccination hesitancy or refusal (15.5% vs 6.8% among all participants, P < 0.001). 40.0% participants intended to accept COVID-19 vaccination, and those in private sector (OR: 1.67, 95%CI: 1.11–2.51), with chronic conditions (OR: 1.83, 95%CI: 1.22–2.77), encountering with suspected or confirmed COVID-19 patients (OR: 1.63, 95%CI: 1.14–2.33), accepted influenza vaccination in 2019 (OR: 2.03, 95%CI: 1.47–2.81) had higher intentions to accept it. Reasons for refusal and hesitation for COVID-19 vaccination included “suspicion on efficacy, effectiveness and safety”, “believing it unnecessary”, and “no time to take it”.ConclusionWith a low level of COVID-19 acceptance intentions and high proportion of hesitation in both influenza and COVID-19 vaccination, evidence-based planning are needed to improve the uptake of both vaccinations in advance of their implementation. Future studies are needed to explore reasons of change of influenza vaccination acceptance, look for actual behaviour patterns of COVID-19 vaccination acceptance and examine effectiveness of promotion strategies.     

Factors associated with COVID-19 vaccination during June–October 2021: A multi-site prospective study

IntroductionVaccine hesitancy presents a challenge to COVID-19 control efforts. To identify beliefs associated with delayed vaccine uptake, we developed and implemented a vaccine hesitancy survey for the COVID-19 Community Research Partnership.MethodsIn June 2021, we assessed attitudes and beliefs associated with COVID-19 vaccination using an online survey. Self-reported vaccination data were requested daily through October 2021. We compared responses between vaccinated and unvaccinated respondents using absolute standardized mean differences (ASMD). We assessed validity and reliability using exploratory factor analysis and identified latent factors associated with a subset of survey items. Cox proportional hazards models and mediation analyses assessed predictors of subsequent vaccination among those initially unvaccinated.ResultsIn June 2021, 29,522 vaccinated and 1,272 unvaccinated participants completed surveys. Among those unvaccinated in June 2021, 559 (43.9 %) became vaccinated by October 31, 2021. In June, unvaccinated participants were less likely to feel “very concerned” about getting COVID-19 than vaccinated participants (10.6 % vs. 43.3 %, ASMD 0.792). Among those initially unvaccinated, greater intent to become vaccinated was associated with getting vaccinated and shorter time to vaccination. However, even among participants who reported no intention to become vaccinated, 28.5 % reported vaccination before study end. Two latent factors predicted subsequent vaccination—being ‘more receptive’ was derived from motivation to protect one’s own or others’ health and resume usual activities; being ‘less receptive’ was derived from concerns about COVID-19 vaccines. In a Cox model, both factors were partially mediated by vaccination intention.ConclusionThis study characterizes vaccine hesitant individuals and identifies predictors of eventual COVID-19 vaccination through October 31, 2021. Even individuals with no intention to be vaccinated can shift to vaccine uptake. Our data suggest factors of perceived severity of COVID-19 disease, vaccine safety, and trust in the vaccine development process are predictive of vaccination and may be important opportunities for ongoing interventions.     

Declining influenza vaccination rates in an underserved pediatric primary care center during the COVID-19 pandemic

BackgroundInfluenza vaccination rates are decreasing in the United States. Disinformation surrounding COVID-related public health protections and SARS-CoV-2 vaccine roll-out may have unintended consequences impacting pediatric influenza vaccination. We assessed influenza vaccination rates before and during the COVID-19 pandemic in one pediatric primary care center, serving a minoritized population.MethodsA cross-sectional study assessed influenza vaccination rates for children aged 6 months to 12 years over the following influenza seasons (September-May): 1) 2018–19 and 2019–20 (pre-pandemic), and 2) 2020–21 and 2021–22 (intra-pandemic). Demographics and responses to social risk questionnaires were extracted from electronic health records. Total tetanus vaccinations across influenza seasons served as approximations of general vaccination rates. Generalized linear regression models with robust standard errors evaluated differences in demographics, social risks, and influenza vaccination rates by season. Multivariable logistic regression with robust standard errors evaluated associations between influenza season, demographics, social risks, and influenza vaccination.ResultsMost patients were young (mean age ～ 6 years), non-Hispanic Black (～80%), and publicly insured (～90%). Forty-two percent of patients eligible to receive the influenza vaccine who were seen in 2019–20 influenza season received the influenza vaccine, compared to 30% in 2021–22. Influenza and tetanus vaccination rates decreased during the COVID-19 pandemic (p < 0.01). The 2020–21 and 2021–22 influenza seasons, older age, Black race, and self-pay were associated with decreased influenza vaccine administration (p < 0.05).ConclusionsInfluenza vaccination rates within one pediatric primary care center decreased during the COVID-19 pandemic and have not rebounded, particularly for older children, those identifying as Black, and those without insurance.     

Tree-based data mining for safety assessment of first COVID-19 booster doses in the Vaccine Safety Datalink

BackgroundThe Centers for Disease Control and Prevention’s Vaccine Safety Datalink (VSD) has been performing safety surveillance for COVID-19 vaccines since their earliest authorization in the United States. Complementing its real-time surveillance for pre-specified health outcomes using pre-specified risk intervals, the VSD conducts tree-based data-mining to look for clustering of a broad range of health outcomes after COVID-19 vaccination. This study’s objective was to use this untargeted, hypothesis-generating approach to assess the safety of first booster doses of Pfizer-BioNTech (BNT162b2), Moderna (mRNA-1273), and Janssen (Ad26.COV2.S) COVID-19 vaccines.MethodsVSD enrollees receiving a first booster of COVID-19 vaccine through April 2, 2022 were followed for 56 days. Incident diagnoses in inpatient or emergency department settings were analyzed for clustering within both the hierarchical ICD-10-CM code structure and the follow-up period. The self-controlled tree-temporal scan statistic was used, conditioning on the total number of cases for each diagnosis. P-values were estimated by Monte Carlo simulation; p = 0.01 was pre-specified as the cut-off for statistical significance of clusters.ResultsMore than 2.4 and 1.8 million subjects received Pfizer-BioNTech and Moderna boosters after an mRNA primary series, respectively. Clusters of urticaria/allergy/rash were found during Days 10–15 after the Moderna booster (p = 0.0001). Other outcomes that clustered after mRNA boosters, mostly with p = 0.0001, included unspecified adverse effects, common vaccine-associated reactions like fever and myalgia, and COVID-19. COVID-19 clusters were in Days 1–10 after booster receipt, before boosters would have become effective. There were no noteworthy clusters after boosters following primary Janssen vaccination.ConclusionsIn this untargeted data-mining study of COVID-19 booster vaccination, a cluster of delayed-onset urticaria/allergy/rash was detected after the Moderna booster, as has been reported after Moderna vaccination previously. Other clusters after mRNA boosters were of unspecified or common adverse effects and COVID-19, the latter evidently reflecting immunity to COVID-19 after 10 days.     

Myocarditis following COVID-19 mRNA vaccination

BackgroundClinical trials of the BNT162b2 vaccine, revealed efficacy and safety. We report six cases of myocarditis, which occurred shortly after BNT162b2 vaccination.MethodsPatients were identified upon presentation to the emergency department with symptoms of chest pain/discomfort. In all study patients, we excluded past and current COVID-19. Routine clinical and laboratory investigations for common etiologies of myocarditis were performed. Laboratory tests also included troponin and C-reactive protein levels. The diagnosis of myocarditis was established after cardiac MRI.FindingsFive patients presented after the second and one after the first dose of the vaccine. All patients were males with a median age of 23 years. Myocarditis was diagnosed in all patients, there was no evidence of COVID-19 infection. Laboratory assays excluded concomitant infection; autoimmune disorder was considered unlikely. All patients responded to the BNT162b2 vaccine. The clinical course was mild in all six patients.InterpretationOur report of myocarditis after BNT162b2 vaccination may be possibly considered as an adverse reaction following immunization. We believe our information should be interpreted with caution and further surveillance is warranted.     

Unmet need for COVID-19 vaccination coverage in Kenya

COVID-19 has impacted the health and livelihoods of billions of people since it emerged in 2019. Vaccination for COVID-19 is a critical intervention that is being rolled out globally to end the pandemic. Understanding the spatial inequalities in vaccination coverage and access to vaccination centres is important for planning this intervention nationally. Here, COVID-19 vaccination data, representing the number of people given at least one dose of vaccine, a list of the approved vaccination sites, population data and ancillary GIS data were used to assess vaccination coverage, using Kenya as an example. Firstly, physical access was modelled using travel time to estimate the proportion of population within 1 hour of a vaccination site. Secondly, a Bayesian conditional autoregressive (CAR) model was used to estimate the COVID-19 vaccination coverage and the same framework used to forecast coverage rates for the first quarter of 2022. Nationally, the average travel time to a designated COVID-19 vaccination site (n = 622) was 75.5 min (Range: 62.9 – 94.5 min) and over 87% of the population >18 years reside within 1 hour to a vaccination site. The COVID-19 vaccination coverage in December 2021 was 16.70% (95% CI: 16.66 – 16.74) – 4.4 million people and was forecasted to be 30.75% (95% CI: 25.04 – 36.96) – 8.1 million people by the end of March 2022. Approximately 21 million adults were still unvaccinated in December 2021 and, in the absence of accelerated vaccine uptake, over 17.2 million adults may not be vaccinated by end March 2022 nationally. Our results highlight geographic inequalities at sub-national level and are important in targeting and improving vaccination coverage in hard-to-reach populations. Similar mapping efforts could help other countries identify and increase vaccination coverage for such populations.     

A broad assessment of covid-19 vaccine safety using tree-based data-mining in the vaccine safety datalink

BackgroundExcept for spontaneous reporting systems, vaccine safety monitoring generally involves pre-specifying health outcomes and post-vaccination risk windows of concern. Instead, we used tree-based data-mining to look more broadly for possible adverse events after Pfizer-BioNTech, Moderna, and Janssen COVID-19 vaccination.MethodsVaccine Safety Datalink enrollees receiving ≥1 dose of COVID-19 vaccine in 2020–2021 were followed for 70 days after Pfizer-BioNTech or Moderna and 56 days after Janssen vaccination. Incident diagnoses in inpatient or emergency department settings were analyzed for clustering within both the hierarchical ICD-10-CM code structure and the post-vaccination follow-up period. We used the self-controlled tree-temporal scan statistic and TreeScan software. Monte Carlo simulation was used to estimate p-values; p = 0.01 was the pre-specified cut-off for statistical significance of a cluster.ResultsThere were 4.1, 2.6, and 0.4 million Pfizer-BioNTech, Moderna, and Janssen vaccinees, respectively. Clusters after Pfizer-BioNTech vaccination included: (1) unspecified adverse effects, (2) common vaccine reactions, such as fever, myalgia, and headache, (3) myocarditis/pericarditis, and (4) less specific cardiac or respiratory symptoms, all with the strongest clusters generally after Dose 2; and (5) COVID-19/viral pneumonia/sepsis/respiratory failure in the first 3 weeks after Dose 1. Moderna results were similar but without a significant myocarditis/pericarditis cluster. Further investigation suggested the fifth signal group was a manifestation of mRNA vaccine effectiveness after the first 3 weeks. Janssen vaccinees had clusters of unspecified or common vaccine reactions, gait/mobility abnormalities, and muscle weakness. The latter two were deemed to have arisen from confounding related to practices at one site.ConclusionsWe detected post-vaccination clusters of unspecified adverse effects, common vaccine reactions, and, for the mRNA vaccines, chest pain and palpitations, as well as myocarditis/pericarditis after Pfizer-BioNTech Dose 2. Unique advantages of this data mining are its untargeted nature and its inherent adjustment for the multiplicity of diagnoses and risk intervals scanned.     

COVID-19 vaccination among different types of US Healthcare Personnel

BackgroundIncreasing vaccine coverage remains the best way to control the COVID-19 pandemic. Healthcare personnel (HCP) have long been the most credible and frequently used source of vaccine information for the public, and an HCP recommendation is a strong predictor of vaccination.MethodsA survey of HCP was conducted in September 2021 via a double opt-in network panel. Responses to survey items were summarized and stratified by HCP type and adjusted logistic regression models were fitted.Results>94% of the 1074 HCP surveyed reported receiving at least one dose of COVID-19 vaccine or intending to soon, with vaccinating most common among pediatricians (98%), followed by family medicine doctors (96%), pharmacists (94%), and nurses/nurse practitioners/physician assistants (88%). HCP with high trust in the Centers for Disease Control and Prevention had 26 times the odds of vaccinating of HCP with low trust (95%CI: 9, 74). Nearly half of unvaccinated HCP (47%) were concerned about side effects, and one third of unvaccinated HCP (33%) were concerned the vaccine was developed too quickly. About three quarters of HCP reported strongly recommending the Pfizer-BioNTech (75%) and Moderna (70%) vaccines to their patients, compared to about one quarter (24%) strongly recommending Johnson & Johnson.ConclusionsAlthough most HCP are vaccinated against COVID-19 and strongly recommend vaccination to their patients, some harbor similar concerns to the public. Additional resources – regularly updated to explain the progressing scientific landscape and address ever evolving public concerns – are needed to further improve vaccine coverage among HCP and aid them in supporting the decision-making of their patients.     

Safety of COVID-19 vaccination and acute neurological events: A self-controlled case series in England using the OpenSAFELY platform

IntroductionWe investigated the potential association of COVID-19 vaccination with three acute neurological events: Guillain-Barré syndrome (GBS), transverse myelitis and Bell’s palsy.MethodsWith the approval of NHS England we analysed primary care data from >17 million patients in England linked to emergency care, hospital admission and mortality records in the OpenSAFELY platform. Separately for each vaccine brand, we used a self-controlled case series design to estimate the incidence rate ratio for each outcome in the period following vaccination (4–42 days for GBS, 4–28 days for transverse myelitis and Bell’s palsy) compared to a within-person baseline, using conditional Poisson regression.ResultsAmong 7,783,441 ChAdOx1 vaccinees, there was an increased rate of GBS (N = 517; incidence rate ratio 2·85; 95% CI2·33–3·47) and Bell’s palsy (N = 5,350; 1·39; 1·27–1·53) following a first dose of ChAdOx1 vaccine, corresponding to 11.0 additional cases of GBS and 17.9 cases of Bell’s palsy per 1 million vaccinees if causal. For GBS this applied to the first, but not the second, dose. There was no clear evidence of an association of ChAdOx1 vaccination with transverse myelitis (N = 199; 1·51; 0·96–2·37). Among 5,729,152 BNT162b2 vaccinees, there was no evidence of any association with GBS (N = 283; 1·09; 0·75–1·57), transverse myelitis (N = 109; 1·62; 0·86–3·03) or Bell’s palsy (N = 3,609; 0·89; 0·76–1·03). Among 255,446 mRNA-1273 vaccine recipients there was no evidence of an association with Bell’s palsy (N = 78; 0·88, 0·32–2·42).ConclusionsCOVID-19 vaccines save lives, but it is important to understand rare adverse events. We observed a short-term increased rate of Guillain-Barré syndrome and Bell’s palsy after first dose of ChAdOx1 vaccine. The absolute risk, assuming a causal effect attributable to vaccination, was low.