Effectiveness of Vaccines and Antiviral Drugs in Preventing Severe and Fatal COVID-19, Hong Kong.

We compared the effectiveness and interactions of molnupiravir and nirmatrelvir/ritonavir and 2 vaccines, CoronaVac and Comirnaty, in a large population of inpatients with COVID-19 in Hong Kong. Both the oral antiviral drugs and vaccines were associated with lower risks for all-cause mortality and progression to serious/critical/fatal conditions (study outcomes). No significant interaction effects were observed between the antiviral drugs and vaccinations; their joint effects were additive. If antiviral drugs were prescribed within 5 days of confirmed COVID-19 diagnosis, usage was associated with lower risks for the target outcomes for patients >60, but not <60, years of age; no significant clinical benefit was found if prescribed beyond 5 days. Among patients >80 years of age, 3-4 doses of Comirnaty vaccine were associated with significantly lower risks for target outcomes. Policies should encourage COVID-19 vaccination, and oral antivirals should be made accessible to infected persons within 5 days of confirmed diagnosis.

Immune response to mRNA-based COVID-19 booster vaccination in people living with HIV.

OBJECTIVES: Our objective was to assess immune responses and their influencing factors in people living with HIV after messenger RNA (mRNA)-based COVID-19 booster vaccination (third dose). METHODS: This was a retrospective cohort study of people living with HIV who received booster vaccination with BNT-162b2 or mRNA-1273 between October 2021 and January 2022. We assessed anti-spike receptor-binding domain (RBD) immunoglobulin G (IgG), virus neutralizing activity (VNA) titres reported as 100% inhibitory dilution (ID100 ), and T-cell response (using interferon-gamma-release-assay [IGRA]) at baseline and quarterly follow-up visits. Patients with reported COVID-19 during follow-up were excluded. Predictors of serological immune response were analyzed using multivariate regression models. RESULTS: Of 84 people living with HIV who received an mRNA-based booster vaccination, 76 were eligible for analysis. Participants were on effective antiretroviral therapy (ART) and had a median of 670 CD4+ cells/µL (interquartile range [IQR] 540-850). Following booster vaccination, median anti-spike RBD IgG increased by 705.2 binding antibody units per millilitre (BAU/mL) and median VNA titres increased by 1000 ID100 at the follow-up assessment (median 13 weeks later). Multivariate regression revealed that time since second vaccination was a predictor of stronger serological responses (p < 0.0001). No association was found for other factors, including CD4+ status, choice of mRNA vaccine, or concomitant influenza vaccination. In total, 45 patients (59%) had a reactive baseline IGRA, of whom two lost reactivity during follow-up. Of 31 patients (41%) with non-reactive baseline IGRA, 17 (55%) converted to reactive and seven (23%) remained unchanged following booster vaccination. CONCLUSIONS: People living with HIV with ≥500 CD4+ cells/µL showed favourable immune responses to mRNA-based COVID-19 booster vaccination. A longer time (up to 29 weeks) since second vaccination was associated with higher serological responses, whereas choice of mRNA vaccine or concomitant influenza vaccination had no impact.

Prolonged headache with vaccine- and dose-specific headache pattern associated with vaccine against SARS-CoV-2 in patients with migraine.

OBJECTIVE: To examine SARS-CoV-2 vaccine-related headache characteristics and risk factors in migraine patients. METHODS: This retrospective cohort study included 732 migraine patients who had AstraZeneca Vaxzevria, Pfizer-BioNTech Comirnaty, or Moderna Spikevax vaccines. Participants provided information through questionnaires and headache diaries. Headache frequency before and after vaccination and factors associated with headache risk were examined. RESULTS: Approximately a third of patients reported increased headache the day after having primary and booster doses, with mean increase ± SD of 1.9 ± 1.2 and 1.8 ± 1.1 days/week, respectively. Proportions of migraine patients with headache (after vaccination vs. before vaccination) increased after having primary-dose Vaxzevria (35.3% vs. 22.8%, p < 0.001) but not Spikevax (23.8% vs. 26.7%, p = 0.700) or Comirnaty (33.2% vs. 25.8%, p = 0.058). Headache proportion increased after having all three boosters (Vaxzevria 27.1% vs. 17.9% p = 0.003; Comirnaty 34.1% vs. 24.5% p = 0.009; Spikevax 35.2% vs. 24.8% p = 0.031). For primary dose with Vaxzevria and Comirnaty, headache risk increased on the vaccination day, peaked on the day after vaccination, and subsided within a week, while for Spikevax headache risk rose gradually after vaccination, peaked on the seventh post-vaccination day and subsided subsequently. For booster dose, headache risk generally increased on the vaccination day, peaked on the day after vaccination, and subsided gradually with fluctuating pattern within a month. Our study also showed that headache increased on the day before primary dose but not booster dose vaccination and it may be attributable to stress associated with having to undertake new vaccines. Multivariable analyses showed that depression was associated with headache. CONCLUSION: Prolonged headache with vaccine- and dose-specific headache pattern was found. Patients with higher risks of vaccine-related headache must be informed of the potential worsening headache.

COVID-19 vaccine effectiveness in children by age groups. A population-based study in Galicia, Spain.

BACKGROUND: Studies on vaccine effectiveness (VE) against COVID-19 in the pediatric population are outgoing. We aimed to quantify VE against SARS-CoV-2 in two pediatric age groups, 5-11 and 12-17-year-old, while considering vaccine type, SARS-CoV-2 variant, and duration of protection. METHODS: A population-based test-negative control study was undertaken in Galicia, Spain. Children 5-11-year-old received the Comirnaty® (Pfizer, US) vaccine, while those aged 12-17-year-old received the Comirnaty® (Pfizer, US) or SpikeVax® (ModernaTX, Inc) vaccine. Participants were categorized into unvaccinated (0 doses or one dose with <14 days since vaccination), partially vaccinated (only one dose with ≥14 days, or two doses with <14 days after the second dose administration), and fully vaccinated (two doses with ≥14 days after the second injection). Adjusted odds ratios (OR) and their 95% confidence intervals (CI) were estimated using multiple logistic regression models. VE was calculated as (1-OR) * 100. Stratified and sensitivity analyses were performed. RESULTS: In the fully vaccinated 5-11-year-old children, VE against the Omicron variant was 44.1% (95% CI: 38.2%-49.4%). In the fully vaccinated 12-17-year-old individuals, VE was 83.4% (95% CI: 81.2%-85.3%) against Delta and 74.8% (95% CI: 58.5%-84.9%) against Omicron. Comirnaty® and SpikeVax® vaccines showed a similar magnitude of VE against Delta [Comirnaty® VE: 81.9% (95% CI: 79.3%-84.1%) and SpikeVax® VE: 85.3% (95% CI: 81.9%-88.1%)]. Comirnaty® (Pfizer, US; VE: 79.7%; 95% CI: 50.7%-92.4%) showed a slightly higher magnitude of protection against Omicron than SpikeVax® (ModernaTX, Inc), yet with an overlapping CI (VE: 74.3%; 95% CI: 56.6%-84.9%). VE was maintained in all age subgroups in both pediatric populations, but it declined over time. CONCLUSIONS: In Galicia, mRNA VE was moderate against SARS-CoV-2 infections in the 5-11-year-old populations, but high in older children. VE declined over time, suggesting a potential need for booster dose schedules.

Adverse event reports of anaphylaxis after Comirnaty and Vaxzevria COVID-19 vaccinations, Western Australia, 22 February to 30 June 2021.

Within the first 4 months of the Western Australian COVID-19 immunisation programme, 49 suspected anaphylaxis cases were reported to the vaccine safety surveillance system. Twelve reports met Brighton Collaboration case definition, corresponding to rates of 15.9 and 17.7 per million doses of Vaxzevria and Comirnaty administered respectively.

mRNA Vaccines against SARS-CoV-2: Advantages and Caveats.

The application of BNT162b2 and mRNA-1273 vaccines against SARS-CoV-2 infection has constituted a determinant resource to control the COVID-19 pandemic. Since the beginning of 2021, millions of doses have been administered in several countries of North and South America and Europe. Many studies have confirmed the efficacy of these vaccines in a wide range of ages and in vulnerable groups of people against COVID-19. Nevertheless, the emergence and selection of new variants have led to a progressive decay in vaccine efficacy. Pfizer-BioNTech and Moderna developed updated bivalent vaccines-Comirnaty and Spikevax-to improve responses against the SARS-CoV-2 Omicron variants. Frequent booster doses with monovalent or bivalent mRNA vaccines, the emergence of some rare but serious adverse events and the activation of T-helper 17 responses suggest the need for improved mRNA vaccine formulations or the use of other types of vaccines. In this review, we discuss the advantages and limitations of mRNA vaccines targeting SARS-CoV-2 focusing on the most recent, related publications.

Epidemiology of Acute Myocarditis/Pericarditis in Hong Kong Adolescents Following Comirnaty Vaccination.

BACKGROUND: Age-specific incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination in Asia is lacking. This study aimed to study the clinical characteristics and incidence of acute myocarditis/pericarditis among Hong Kong adolescents following Comirnaty vaccination. METHODS: This is a population cohort study in Hong Kong that monitored adverse events following immunization through a pharmacovigilance system for coronavirus disease 2019 (COVID-19) vaccines. All adolescents aged between 12 and 17 years following Comirnaty vaccination were monitored under the COVID-19 vaccine adverse event response and evaluation program. The clinical characteristics and overall incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination were analyzed. RESULTS: Between 14 June 2021 and 4 September 2021, 33 Chinese adolescents who developed acute myocarditis/pericarditis following Comirnaty vaccination were identified. In total, 29 (87.88%) were male and 4 (12.12%) were female, with a median age of 15.25 years. And 27 (81.82%) and 6 (18.18%) cases developed acute myocarditis/pericarditis after receiving the second and first dose, respectively. All cases are mild and required only conservative management. The overall incidence of acute myocarditis/pericarditis was 18.52 (95% confidence interval [CI], 11.67-29.01) per 100 000 persons vaccinated. The incidence after the first and second doses were 3.37 (95% CI, 1.12-9.51) and 21.22 (95% CI, 13.78-32.28 per 100 000 persons vaccinated, respectively. Among male adolescents, the incidence after the first and second doses were 5.57 (95% CI, 2.38-12.53) and 37.32 (95% CI, 26.98-51.25) per 100 000 persons vaccinated. CONCLUSIONS: There is a significant increase in the risk of acute myocarditis/pericarditis following Comirnaty vaccination among Chinese male adolescents, especially after the second dose.

Severe Acute Respiratory Syndrome Coronavirus 2 Adaptive Immunity in Nursing Home Residents Following a Third Dose of the Comirnaty Coronavirus Disease 2019 Vaccine.

A third Comirnaty vaccine dose increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain antibody levels (median, 93-fold) and neutralizing antibody titers against Wuhan-Hu-1 (median, 57-fold), Beta (me 22-fold), Delta, (median, 43-fold), and Omicron (median, 8-fold) variants, but had less impact on S-reactive T-cell immunity in nursing home residents.

SARS-CoV-2 Delta-variant breakthrough infections in nursing home residents at midterm after Comirnaty® COVID-19 vaccination.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant breakthrough infections in nursing home residents following vaccination with Comirnaty® COVID-19 vaccine were characterized. In total, 201 participants (median age, 87 years; range, 64-100; 133 female) from two nursing homes in the Valencian community (Spain) were included. SARS-CoV-2-Spike (S) antibody responses were determined by a lateral flow immunocromatography (LFIC) assay and by quantitative electrochemiluminescent assay in LFIC-negative participants. SARS-CoV-2-S-IFNγ T cells were enumerated by flow cytometry in 10 participants. Nasopharyngeal SARS-CoV-2 RNA loads were quantified by real-time polymerase chain reaction assays. Vaccine breakthrough COVID-19 due to the Delta variant occurred in 39 residents (median age, 87 years; range, 69-96; 31 female) at a median of 6.5 months after vaccination (nine requiring hospitalization). Breakthrough infections occurred at a higher rate (p < 0.0001) in residents who had not been previously infected with SARS-CoV-2 (naïve) (33/108; 18%) than in those with prior diagnosis of SARS-CoV-2 infection (experienced) (6/93; 6.4%), and were more likely (p < 0.0001) to develop in residents who tested negative by LFIC (20/49) at 3 months after vaccination as compared to their LFIC-positive counterparts (19/142). Among LFIC-negative residents, a trend towards lower plasma anti-RBD antibody levels was noticed in those developing breakthrough infection (p = 0.16). SARS-CoV-2 RNA loads in nasopharyngeal specimens were lower in SARS-CoV-2-experienced residents (p < 0.001) and in those testing positive by LFIC (p = 0.13). The frequency of SARS-CoV-2-S-reactive T cells at 3 months was similar in LFIC-negative residents with (n = 7) or without (n = 3) breakthrough infection. Prior history of SARS-CoV-2 infection and detection of S-reactive antibodies by LFIC at 3 months is associated with a lower risk of Delta-variant breakthrough infection in nursing home residents at midterm after Comirnaty® COVID-19 vaccination.

SARS-CoV-2 Omicron BA.1 variant breakthrough infections in nursing home residents after an homologous third dose of the Comirnaty® COVID-19 vaccine: Looking for correlates of protection.

We investigated whether peripheral blood levels of SARS-CoV-2 Spike (S) receptor binding domain antibodies (anti-RBD), neutralizing antibodies (NtAb) targeting Omicron S, and S-reactive-interferon (IFN)-γ-producing CD4+ and CD8+ T cells measured after a homologous booster dose (3D) with the Comirnaty® vaccine was associated with the likelihood of subsequent breakthrough infections due to the Omicron variant. An observational study including 146 nursing home residents (median age, 80 years; range, 66-99; 109 female) evaluated for an immunological response after 3D (at a median of 16 days). Anti-RBD total antibodies were measured by chemiluminescent immunoassay. NtAb were quantified by an Omicron S pseudotyped virus neutralization assay. SARS-CoV-2-S specific-IFNγ-producing CD4+ and CD8+ T cells were enumerated by whole-blood flow cytometry for intracellular cytokine staining. In total, 33/146 participants contracted breakthrough Omicron infection (symptomatic in 30/33) within 4 months after 3D. Anti-RBD antibody levels were comparable in infected and uninfected participants (21 123 vs. 24 723 BAU/ml; p = 0.34). Likewise, NtAb titers (reciprocal IC50 titer, 157 vs. 95; p = 0.32) and frequency of virus-reactive CD4+ (p = 0.82) and CD8+ (p = 0.91) T cells were similar across participants in both groups. anti-RBD antibody levels and NtAb titers estimated at around the time of infection were also comparable (3445 vs. 4345 BAU/ml; p = 0.59 and 188.5 vs. 88.9; p = 0.70, respectively). Having detectable NtAb against Omicron or SARS-CoV-2-S-reactive-IFNγ-producing CD4+ or CD8+ T cells after 3D was not correlated with increased protection from breakthrough infection (OR, 1.50; p = 0.54; OR, 0.0; p = 0.99 and OR 3.70; p = 0.23, respectively). None of the immune parameters evaluated herein, including NtAb titers against the Omicron variant, may reliably predict at the individual level the risk of contracting COVID-19 due to the Omicron variant in nursing home residents.

Neutralizing antibody titers six months after Comirnaty vaccination: kinetics and comparison with SARS-CoV-2 immunoassays.

OBJECTIVES: mRNA vaccines, including Comirnaty (BNT162b2 mRNA, BioNTech-Pfizer), elicit high IgG and neutralizing antibody (NAb) responses after the second dose, but the progressive decrease in serum antibodies against SARS-CoV-2 following vaccination have raised questions concerning long-term immunity, decreased antibody levels being associated with breakthrough infections after vaccination, prompting the consideration of booster doses. METHODS: A total number of 189 Padua University-Hospital healthcare workers (HCW) who had received a second vaccine dose were asked to collect serum samples for determining Ab at 12 (t12) and 28 (t28) days, and 6 months (t6m) after their first Comirnaty/BNT162b2 inoculation. Ab titers were measured with plaque reduction neutralization test (PRNT), and three chemiluminescent immunoassays, targeting the receptor binding domain (RBD), the trimeric Spike protein (trimeric-S), and surrogate viral neutralization tests (sVNT). RESULTS: The median percentages (interquartile range) for decrease in antibodies values 6 months after the first dose were 86.8% (67.1-92.8%) for S-RBD IgG, 82% (58.6-89.3%) for trimeric-S, 70.4% (34.5-86.4%) for VNT-Nab, 75% (50-87.5%) for PRNT50 and 75% (50-93.7%) for PRNT90. At 6 months, neither PRNT titers nor VNT-Nab and S-RBD IgG bAb levels correlated with age (p=0.078) or gender (p=0.938), while they were correlated with previous infection (p<0.001). CONCLUSIONS: After 6 months, a method-independent reduction of around 90% in anti-SARS-CoV-2 antibodies was detected, while no significant differences were found between values of males and females aged between 24 and 65 years without compromised health status. Further efforts to improve analytical harmonization and standardization are needed.

A systematic review on mucocutaneous presentations after COVID-19 vaccination and expert recommendations about vaccination of important immune-mediated dermatologic disorders.

With dermatologic side effects being fairly prevalent following vaccination against COVID-19, and the multitude of studies aiming to report and analyze these adverse events, the need for an extensive investigation on previous studies seemed urgent, in order to provide a thorough body of information about these post-COVID-19 immunization mucocutaneous reactions. To achieve this goal, a comprehensive electronic search was performed through the international databases including Medline (PubMed), Scopus, Cochrane, Web of science, and Google scholar on July 12, 2021, and all articles regarding mucocutaneous manifestations and considerations after COVID-19 vaccine administration were retrieved using the following keywords: COVID-19 vaccine, dermatology considerations and mucocutaneous manifestations. A total of 917 records were retrieved and a final number of 180 articles were included in data extraction. Mild, moderate, severe and potentially life-threatening adverse events have been reported following immunization with COVID vaccines, through case reports, case series, observational studies, randomized clinical trials, and further recommendations and consensus position papers regarding vaccination. In this systematic review, we categorized these results in detail into five elaborate tables, making what we believe to be an extensively informative, unprecedented set of data on this topic. Based on our findings, in the viewpoint of the pros and cons of vaccination, mucocutaneous adverse events were mostly non-significant, self-limiting reactions, and for the more uncommon moderate to severe reactions, guidelines and consensus position papers could be of great importance to provide those at higher risks and those with specific worries of flare-ups or inefficient immunization, with sufficient recommendations to safely schedule their vaccine doses, or avoid vaccination if they have the discussed contra-indications.

Status migrainosus: a potential adverse reaction to Comirnaty (BNT162b2, BioNtech/Pfizer) COVID-19 vaccine-a case report.

BACKGROUND: Coronavirus disease-19 (COVID-19) due to acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is the largest emergency that humanity had to be dealing with in the last century. During the last months, different types of vaccines have been designed to contain the ongoing SARS-CoV-2 pandemic, with successful results in many countries. Comirnaty (Pfizer/BioNtech) COVID-19 vaccine is a lipid nanoparticle-formulated, nucleoside mRNA vaccine encoding the prefusion spike glycoprotein of SARS-CoV-2. Although vaccines have an undeniable efficacy, they can also present several neurological side effects, including headache. According to ICHD-3 Classification, status migrainosus (SMg) is described as a debilitating migraine attack lasting for more than 72 h. Symptoms of SMg can be very severe, preventing the normal daily activities of the individual. CASE PRESENTATION: In the present report, we describe a case of SMg that lasted 11 days, time correlated with the second dose of COVID-19 vaccine (Pfizer/Comirnaty) in a 37-year-old woman with a history of migraine without aura. CONCLUSIONS: In patients with a history of migraine, COVID-19 vaccination could lead to a worsening of headache and, in rare cases, to the development of a SMg. This may be related to the inflammatory response that occurs after vaccination.

Antibody response after two doses of the SARS-CoV-2 Comirnaty vaccine in a Covid-19 positive and Covid-19 negative Italian healthcare workers cohort.

BACKGROUND: Extensive vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now universally regarded as one of the most effective strategies for counteracting the current pandemic. The durability of the immune response of available vaccines is not known, therefore the quantitative dynamics of serum anti-S antibodies after Comirnaty vaccine in health care workers (HCW) of Desio Hospital was conducted. METHODS: 51 previously infected and 198 not infected HCW, from Desio, Italy were enrolled in the study. Comirnaty double dose schedule was completed by each subject. Specific anti-S antibodies against the SARS-CoV-2 S protein were measured by ECLIA in sequential blood samples. RESULTS: A significant difference was observed beginning at pre priming dose (T0) of the anti-S antibodies between the two subgroups which persisted throughout the study (4 months). A significant reduction occurred after 4 months post-priming dose (T3). Finally, a subgroup of low and late responders with an increasing trend was found. CONCLUSIONS: Specific anti-S antibodies are significantly decreased 4 months post priming dose of Comirnaty vaccine although prior COVID-19 infection seems to escalate humoral response. Further evaluation concerning antibody persistence beyond this point, and the proportion of neutralizing antibodies with higher affinity towards SARS-CoV-2 is needed, especially in naїve and immunosuppressed subjects.

Response to three doses of the Pfizer/BioNTech BNT162b2 COVID-19 vaccine: a retrospective study of a cohort of haemodialysis patients in France.

BACKGROUND: The mortality rate associated with coronavirus disease 2019 (COVID-19) is high among haemodialyzed patients. We sought to describe the serological status of haemodialysis patients having received up to three doses of BNT162b2 mRNA vaccine, and to identify factors associated with a poor humoral response. METHODS: We performed a retrospective, observational study of patients attending a dialysis centre in Antibes, France. One or two of each patient's monthly venous blood samples were assayed for anti-spike (S1) immunoglobulin G (IgG). RESULTS: We included 142 patients, of whom 124 remained COVID-19-negative throughout the study. Among these COVID-19-negative patients, the humoral immune response rate (defined as an anti-S1 IgG titre ≥1.2 U/ml) was 82.9% after two injections and 95.8% after three injections, and the median [interquartile range] titre increased significantly from 7.09 [2.21; 19.94] U/ml with two injections to 93.26 [34.25; 176.06] U/ml with three. Among patients with two injections, the mean body mass index and serum albumin levels were significantly higher in responders than in non-responders (26.5 kg/m2 vs. 23.2 kg/m2, p = 0.0392; and 41.9 g/l vs. 39.0 g/l, p = 0.0042, respectively). For the study population as a whole at the end of the study, a history of COVID-19, at least two vaccine doses, and being on the French national waiting list for kidney transplantation were the only factors independently associated with the anti-S1 IgG titre. CONCLUSIONS: Dialysis patients vaccinated with two doses of BNT162b2 might not be sufficiently protected against SARS-CoV-2 and so should receive a third (booster) dose. TRIAL REGISTRATION: The present retrospective study of clinical practice was not interventional and so was not registered.

A Cross-Sectional Study of Untoward Reactions Following Homologous and Heterologous COVID-19 Booster Immunizations in Recipients Seventeen Years of Age and Older.

A booster dose after primary COVID-19 vaccination series was considered crucial after the emergence of the B.1.617.2 (Delta) and B.1.1.529 (Omicron) variants. Active surveillance was used to investigate reporting of adverse events post-booster dose of either of the licensed mRNA Comirnaty (Pfizer/BioNTech) or Spikevax (Moderna) vaccines in adult (17 years and older) recipients in central Italy. Eligible participants were enrolled and interviewed via phone using a structured questionnaire. Primary outcomes related to the occurrence of adverse events post-booster were stratified by vaccine, and frequency of local/systemic, mild/moderate/severe events. Of a total of 622 participants interviewed, 554 (89.1%) reported at least one adverse event (88.2% and 92.9% after the Comirnaty or Spikevax vaccine, respectively): 63.4% were female, and 78.5% aged 17 to 64 years, regardless of vaccine. 87.7% and 68.2% of all recipients described at least one local or systemic reaction, respectively: 97.3, 38.6 and 4.7% reported mild, moderate, or severe events, respectively. The most frequent adverse reactions were pain, redness, or swelling at the injection site and fatigue, while malaise and fever significantly occurred after the Comirnaty, and vomiting after the Spikevax booster. Compared to the primary vaccination, lymphadenopathy was more common after the booster (p < 0.001), especially after Comirnaty vaccine. The study findings revealed no serious or unexpected adverse events, and are in agreement with data available on booster dose for both mRNA vaccines. The transient, mild to moderate, and common to very common side reactions reported should be used to reassure potential recipients of the lack of safety concerns.

Serological responses to COVID-19 Comirnaty booster vaccine, London, United Kingdom, September to December 2021.

Serum samples were collected pre- and post-booster vaccination with Comirnaty in 626 participants (aged ≥ 50 years) who had received two Comirnaty doses < 30 days apart, two Comirnaty doses ≥ 30 days apart or two Vaxzevria doses ≥ 30 days apart. Irrespective of primary vaccine type or schedule, spike antibody GMTs peaked 2-4 weeks after second dose, fell significantly ≤ 38 weeks later and rose above primary immunisation GMTs 2-4 weeks post-booster. Higher post-booster responses were observed with a longer interval between primary immunisation and boosting.

Intramyocardial Inflammation after COVID-19 Vaccination: An Endomyocardial Biopsy-Proven Case Series.

Myocarditis in response to COVID-19 vaccination has been reported since early 2021. In particular, young male individuals have been identified to exhibit an increased risk of myocardial inflammation following the administration of mRNA-based vaccines. Even though the first epidemiological analyses and numerous case reports investigated potential relationships, endomyocardial biopsy (EMB)-proven cases are limited. Here, we present a comprehensive histopathological analysis of EMBs from 15 patients with reduced ejection fraction (LVEF = 30 (14-39)%) and the clinical suspicion of myocarditis following vaccination with Comirnaty® (Pfizer-BioNTech) (n = 11), Vaxzevria® (AstraZenica) (n = 2) and Janssen® (Johnson & Johnson) (n = 2). Immunohistochemical EMB analyses reveal myocardial inflammation in 14 of 15 patients, with the histopathological diagnosis of active myocarditis according the Dallas criteria (n = 2), severe giant cell myocarditis (n = 2) and inflammatory cardiomyopathy (n = 10). Importantly, infectious causes have been excluded in all patients. The SARS-CoV-2 spike protein has been detected sparsely on cardiomyocytes of nine patients, and differential analysis of inflammatory markers such as CD4+ and CD8+ T cells suggests that the inflammatory response triggered by the vaccine may be of autoimmunological origin. Although a definitive causal relationship between COVID-19 vaccination and the occurrence of myocardial inflammation cannot be demonstrated in this study, data suggest a temporal connection. The expression of SARS-CoV-2 spike protein within the heart and the dominance of CD4+ lymphocytic infiltrates indicate an autoimmunological response to the vaccination.

Real-world data shows increased reactogenicity in adults after heterologous compared to homologous prime-boost COVID-19 vaccination, March-June 2021, England.

Adults receiving heterologous COVID-19 immunisation with mRNA (Comirnaty) or adenoviral-vector (Vaxzevria) vaccines had higher reactogenicity rates and sought medical attention more often after two doses than homologous schedules. Reactogenicity was higher among ≤ 50 than > 50 year-olds, women and those with prior symptomatic/confirmed COVID-19. Adults receiving heterologous schedules on clinical advice after severe first-dose reactions had lower reactogenicity after dose 2 following Vaxzevria/Comirnaty (93.4%; 95% confidence interval: 90.5-98.1 vs 48% (41.0-57.7) but not Comirnaty/Vaxzevria (91.7%; (77.5-98.2 vs 75.0% (57.8-87.9).

Early tolerability of Comirnaty vaccine in patients with chronic neurological diseases.

Patients with chronic neurological diseases may have predisposing risk factors for severe COVID-19 and should be considered as priority candidates for SARS-CoV-2 vaccination. Nevertheless, the safety of RNA vaccine was evaluated in healthy volunteers or in patients with stable chronic medical conditions excluding patients with chronic neurological diseases. We report here the early tolerability of Comirnaty vaccine in 36 patients with chronic neurological diseases and demonstrate good early tolerability, better than found in healthy people in phase 3 trials.