Sudden Sensorineural Hearing Loss Following Immunization With BNT162b2 or mRNA-1273: A Danish Population-Based Cohort Study.

OBJECTIVE: To compare the occurrence of sudden sensorineural hearing loss following immunization with BNT162b2 (Comirnaty®; Pfizer BioNTech) or mRNA-1273 (Spikevax®; Moderna) to the occurrence among unvaccinated individuals. STUDY DESIGN: Cohort study. SETTING: Nationwide Danish health care registers comprised all Danish residents living in Denmark on October 1, 2020, who were 18 years or older or turned 18 in 2021. METHODS: We compared the occurrence of sudden sensorineural hearing loss following immunization with BNT162b2 (Comirnaty®; Pfizer BioNTech) or mRNA-1273 (Spikevax®; Moderna) (first, second, or third dose) against unvaccinated person time. Secondary outcomes were a first-ever hospital diagnosis of vestibular neuritis and a hearing examination, by an ear-nose-throat (ENT) specialist, followed by a prescription of moderate to high-dose prednisolone. RESULTS: BNT162b2 or mRNA-1273 vaccine was not associated with an increased risk of receiving a discharge diagnosis of sudden sensorineural hearing loss (adjusted hazard ratio [HR]: 0.99, confidence interval [CI]: 0.59-1.64) or vestibular neuritis (adjusted HR: 0.94, CI: 0.69-1.24). We found a slightly increased risk (adjusted HR: 1.40, CI, 1.08-1.81) of initiating moderate to high-dose oral prednisolone following a visit to an ENT specialist within 21 days from receiving a messenger RNA (mRNA)-based Covid-19 vaccine. CONCLUSION: Our findings do not suggest an increased risk of sudden sensorineural hearing loss or vestibular neuritis following mRNA-based COVID-19 vaccination. mRNA-Covid-19 vaccination may be associated with a small excess risk of a visit to an ENT specialist visit followed by a prescription of moderate to high doses of prednisolone.

Characteristics and outcomes of adverse events after COVID-19 vaccination.

OBJECTIVES: BNT-162b2, mRNA-1273, and Ad26.COV2.S vaccines data regarding adverse events (AEs) are scarce. In this report, we aimed to describe fatal and non-fatal possible AEs after COVID-19 vaccine administration. METHODS: An observational multicenter study investigating the causes of emergency department visits and hospital admissions within 10 days of COVID-19 vaccination. Patients who received first or second doses of COVID-19 vaccines and presented to the emergency department (ED), as well as those admitted to the hospitals or intensive care units (ICUs) were included. Causes of ED, hospital, and ICU admissions and discharges were collected based on the International Classification of Diseases, Tenth Revision (ICD-10) coding system. RESULTS: Between December 2020 and March 2021, 1842 patients visited the ED within 10 days of COVID-19 vaccine administration. The mean age was 70.3 years. Overall, 1221 patients presented after the first dose of the vaccine and 653 after the second dose. Trauma (14.9%), hypertensive emergency/urgency (7.8%), generalized pain and arthralgia (5.7%), and chest pain (4.4%) were the most common causes of presentation to the ED. Of all ED presentations, mortality rate was at 2.2% (41 patients) with a median follow-up time of 68.0 days, versus 2.6% in unvaccinated ED patients. Postvaccination acute hypoxemic respiratory failure (46.3%), septic shock (24.4%), and cardiogenic shock (12.2%) were the most common causes of death. CONCLUSION: Although reported AEs are not necessarily caused by the vaccination, this study provides further information about possible AEs after COVID-19 immunization, especially those requiring hospital admission. This study also supports prior data that serious AEs post vaccination are much lower than primary COVID-19 infections. Further studies are needed to investigate causalities between vaccines and reported AEs across all age groups.

Diversity and inclusion in clinical trials: Evolution throughout the development of an mRNA COVID-19 vaccine.

Despite the importance of equitable representation in clinical trials, disparities persist with racial and ethnic minorities remaining largely underrepresented in trial populations. During the coronavirus disease 2019 (COVID-19) pandemic, wherein disease disproportionately affected racial and ethnic minority groups, the necessity for diverse and inclusive representation in clinical trials has been further highlighted. Considering the urgent need for a safe and efficacious vaccine, COVID-19 vaccine clinical trials faced marked challenges in rapidly enrolling participants without forgoing diverse representation. In this perspective, we summarize Moderna's approach toward achieving equitable representation in mRNA-1273 COVID-19 vaccine clinical trials, including the COVID-19 efficacy (COVE) study, a large, randomized, controlled, phase 3 trial of mRNA-1273 safety and efficacy in adults. We describe the dynamics of enrollment diversity throughout the COVE trial and the need for continuous, efficient monitoring and rapid pivoting from initial approaches to address early challenges. Insights gained from our varied and evolved initiatives provide key learnings toward achieving equitable representation in clinical trials, including establishing and listening to a Diversity and Inclusion Advisory Committee, repeatedly engaging with key stakeholders on the necessity for diverse representation, creating and disseminating inclusive materials to all trial participants, establishing methods to raise awareness for interested participants, and enhancing transparency with trial participants to build trust. This work shows that diversity and inclusion in clinical trials can be attained even in the most extreme circumstances and highlights the importance of efforts toward building trust and empowering racial and ethnic minorities with the knowledge to make informed medical treatment decisions.

Temporal association between COVID-19 vaccination and Raynaud's phenomenon: A case series.

COVID-19 vaccine-related adverse events are mostly minor to moderate, and serious events are rare. Single cases of Raynaud's phenomenon (RP) in temporal proximity to COVID-19 vaccination have been reported. Demographic data, medical history, and detailed information regarding vaccination status and RP characteristics were obtained from patients with confirmed RP after COVID-19 vaccination. Fifteen participants reported the initial manifestation of RP, which occurred in 40% after the first, in 33% after the second, and in 27% after the third vaccination. RP development and occurrence of episodes were not linked to any specific vaccine type. New onset of disease was observed in 40% of the vaccinees after BNT162b2, in 33% after mRNA-1273, and in 27% after ChAdOx1 vaccination. Three out of four participants with preexisting RP prior to COVID-19 vaccination reported aggravation in frequency and intensity after immunization. Although COVID-19 vaccination is pivotal in controlling the pandemic, the observed temporal association between vaccine administration and RP occurrence warrants global activities to support pharmacovigilance for the detection of adverse reactions, one of which may include RP.

Adjustment of Immunosuppressants to Facilitate Anti-COVID-19 Antibody Production after mRNA Vaccination in Liver Transplant Recipients.

Liver transplant recipients are immunocompromised and have low immunogenicity to produce antibodies in anti-COVID-19 vaccination. Whether immunosuppressant adjustment could facilitate anti-COVID-19 antibody production in anti-COVID-19 mRNA vaccination is undetermined. Our patients were informed to temporarily suspend mycophenolate mofetil (MMF) or everolimus (EVR) for 2 weeks during both the 1st and 2nd doses of Moderna mRNA-1273 vaccine. A total of 183 recipients receiving two doses of Moderna mRNA-1273 vaccine were enrolled and grouped into tacrolimus monotherapy (MT, n = 41), and dual therapy with non-adjustment (NA, n = 23), single suspension (SS, n = 19) and double suspension (DS, n = 100) of MMF/EVR in two-dose mRNA vaccination. A total of 155 (84.7%) patients had a humoral response to vaccines in this study. The humoral response rates were 60.9%, 89.5%, 91.0% and 80.5% in NA, SS, DS, and MT group patients, respectively (p = 0.003). Multivariate analysis showed that favorable factors for humoral response were temporary suspension of MMF/EVR and monotherapy, and unfavorable factors were deceased donor liver transplantation, WBC count < 4000/uL, lymphocyte < 20% and tacrolimus trough level ≥ 6.8 ng/mL. In conclusion, temporary two-week suspension of anti-proliferation immunosuppressants could create a window to facilitate antibody production during anti-COVID-19 mRNA vaccination. This concept may be applied to other vaccinations in liver transplant recipients.

Antibody responses to second doses of COVID-19 vaccination in lung cancer patients undergoing treatment.

BACKGROUND: Several reports have revealed that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection tends to have more severe outcomes in cancer patients. Although vaccination reduces the risk of severe disease, data on antibody titers achieved by vaccination is scarce in cancer patients. METHODS: We collected 79 blood samples (69 lung cancer patients and 10 control individuals) and conducted an anti-SARS-CoV-2 antibody assay to compare the antibody titer achieved with current treatment. Sixty-eight patients (86%) received the BNT162 mRNA vaccine and 11 (14%) received the mRNA-1273 vaccine. They were categorized according to the current treatment: control individuals without cancer (cohort A), lung cancer patients who were treated with cytotoxic chemotherapy (cohort B), immunotherapy (cohort C), combination of cytotoxic chemotherapy and immunotherapy (cohort D), tyrosine kinase inhibitors (cohort E), and radiation therapy (cohort F). RESULTS: Among 69 lung cancer patients (cohort B-F), 57 (83%) had adenocarcinoma, and 66 (96%) had advanced-stage cancer. In the anti-SARS-CoV-2 antibody assay, the antibody titer was significantly lower in lung cancer patients than in control individuals (p = 0.01). The median antibody titers were 161 AU/ml in control individuals and 59.9 AU/ml in lung cancer patients. CONCLUSIONS: Antibody titers after the second vaccination were lower in cancer patients than those in healthy individuals. Our findings provide essential information for understanding the benefits and necessity of additional vaccination to prevent SARS-CoV-2 infection in lung cancer patients.

Acquired hemophilia A (AHA) due to anti-SARS-CoV-2 vaccination: A systematic review.

Vaccination against SARS-CoV2 has been the largest vaccination campaign over the past two decades. The aim of this study is to qualitatively assess the reported cases of acquired hemophilia A (AHA) that developed after COVID-19 vaccination to further elaborate on incidence, presentation, treatment, and outcomes.We queried Medline (PubMed), Google Scholar, and Embase databases to find reported cases of AHA after COVID-19 vaccines. We found 14 studies (19 cases) for this descriptive analysis. Most patients were elderly (mean age 73 years) and males (n = 12) with multiple comorbidities. All cases developed after mRNA vaccines - BNT162b2 Pfizer-BioNTech (n = 13) and mRNA-1273 Moderna (n = 6). All except one patient were treated, with the most common therapy being a combination of steroids, immunosuppression, and rFVIII (n = 13). Two patients died due to acute respiratory distress, and gall bladder rupture with persistent bleeding, respectively. While evaluating a patient with bleeding diathesis after COVID-19 vaccination, AHA should be kept in the differential diagnosis. Given the low incidence, we believe that the benefit of vaccination still outweighs the risk of disease acquisition.

Humoral and cellular immunity to SARS-COV-2 after vaccination with mRNA vaccines in PLWH with discordant immune response. Influence of the vaccine administered.

Background: Data on SARS-CoV-2 mRNA vaccine immunogenicity in people living with human immunodeficiency virus (PLWH) and discordant immune response (DIR) are currently limited. Therefore, we compare the immunogenicity of these vaccines in DIR and immunological responders (IR). Methods: A prospective cohort that enrolled 89 participants. Finally, 22 IR and 24 DIR were analyzed before vaccination (T0), one (T1) and six months (T2) after receiving BNT162b2 or mRNA-1273 vaccine. Additionally, 10 IR and 16 DIR were evaluated after a third dose (T3). Anti-S-RBD IgG, neutralizing antibodies (nAb), neutralization activity, and specific memory B cells were quantified. Furthermore, specific CD4+ and CD8+ responses were determined by intracellular cytokine staining and polyfunctionality indexes (Pindex). Results: At T1, all participants developed anti-S-RBD. 100% IR developed nAb compared to 83.3% DIR. Spike-specific B cells were detected in all IR and 21/24 DIR. Memory CD4+ T cells responded in 5/9 IR and 7/9 DIR, mainly based on the expression of IFN-γ and TNF-α, with a higher Pindex in DIR. Memory CD8+ T cells responded in only four participants in each group. At T2, anti-S-RBD and nAb titers were higher in DIR than in IR. In both groups, there was an increase in specific B memory cells, higher in DIR. Six IR and five DIR maintained a specific memory CD4+ response. Memory CD8+ response was preserved in IR but was lost in DIR. In a multivariate linear regression analysis, receiving mRNA-1273 instead of BNT162b2 played a prominent role in the results. Conclusions: Our data suggest that PLWH with DIR can mount an immune response similar to those with higher CD4+, provided they receive the mRNA-1273 vaccine instead of others less immunogenic.

Polyarteritis Nodosa Following mRNA-1273 COVID-19 Vaccination: Case Study and Review of Immunological Mechanisms.

Numerous post-vaccine complications have been reported secondary to the COVID-19 vaccine. Many of these complications are believed to be due to a hyperactive immune system. A 59-year-old woman developed diffuse abdominal pain two days after receiving the mRNA-1273 COVID-19 vaccine (Moderna). A computerized tomography (CT) angiogram of the abdomen and pelvis revealed the presence of numerous vascular irregularities in the celiac axis, bilateral renal arteries, and inferior mesenteric artery consistent with polyarteritis nodosa (PAN), a medium-vessel vasculitis. The patient was managed with intravenous methylprednisolone 500 mg daily for three days and was then placed on oral methotrexate (MTX) 12.5 mg daily for immunosuppressive maintenance treatment. Until now, a limited number of cases of polyarteritis nodosa secondary to the COVID-19 vaccine have been reported. Major mechanisms of post-vaccine autoimmunity are molecular mimicry and autoantibody production. Although rare adverse events from COVID-19 vaccination are possible, there remains an immense benefit to vaccination in preventing COVID-19-related morbidity and mortality.

Six-month longitudinal immune kinetics after mRNA-1273 vaccination: Correlation of peak antibody response with long-term, cross-reactive immunity.

Background: The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and the persistence of the pandemic, even with mass coronavirus disease 2019 (COVID-19) vaccination, have raised questions about the durability of immunity and extent of cross-reactive immunity after vaccination. This study aimed to characterize the humoral and cellular immune response to the mRNA-1273 vaccine using a prospective longitudinal cohort. Methods: We recruited 177 young SARS-CoV-2 infection-naive adults. Two doses of mRNA-1273 vaccine were administered at 28-day intervals, and blood samples were collected at five time points: pre-vaccination (T0), 4 weeks after the first (T1) and second dose (T2), and 3 months (T3) and 6 months (T4) after the first dose. Anti-SARS-CoV-2 spike protein (anti-S) IgG antibody, neutralizing antibody, and T-cell immune responses were evaluated. Results: The two-dose mRNA-1273 vaccination induced robust anti-SARS-CoV-2 antibody responses, which remained higher than the titers at T1 until T4. A higher peak anti-S antibody titer at T2 was associated with better cross-reactive immunity against Delta and Omicron variants and long-lasting (anti-S IgG and neutralizing antibody) humoral immunity up to T4. The overall T-cell immune response was not correlated with peak antibody titers (T-lymphocyte subpopulation analysis was not performed). Conclusion: This study showed that an early strong antibody response is predictive of longer humoral immunity and better cross-reactive neutralizing immunity against Delta and Omicron variants.

An observational study of adverse drug reactions to COVID-19 vaccines reported to the New Mexico poison center hotline.

INTRODUCTION: Post-marketing data on coronavirus vaccines are limited. This study evaluated adverse reactions reported to a statewide hotline after the administration of a coronavirus disease-2019 (COVID-19) vaccine. METHODS: We collected reports between 1 December 2020 through 30 August 2021 of any individual 12 years of age and older who received an FDA EUA-approved vaccine and experienced an adverse reaction. For each case, we collected vaccine brand, demographics, adverse reaction type, severity, onset of reaction, duration, and outcome. Relative risk analyses were conducted to investigate factors associated with vaccine adverse reactions. RESULTS: 638 adverse drug reaction cases were recorded. The majority identified as female (70.8%) and the median age was 56. Implicated brands were Pfizer BNT162b2 (46.6%), Moderna mRNA-1273 (43.41%), and Janssen Ad26.COV2.S (8.78%). Although the lowest number of cases was with Janssen, this vaccine had the highest incident rate based on reactions per 100,000 doses. Adverse reactions with the highest incidence were systemic reactions (92.7%), injection-site reactions (8.5%), and local non-injection-site reactions (10.4%), with most judged as minor severity. Relative risk was higher for Moderna compared to Pfizer for injection-site non-severe (RR 2.01) and injection-site severe (RR 1.94) reactions. Janssen had a higher risk of headache, dyspnea, and vision changes compared to Pfizer, and a higher risk of headache compared to Moderna. The relative risk for fever, chills, and lymphadenopathy was higher for the second dose than the first dose for all patients. CONCLUSION: This observational study analyzing adverse drug reactions of the COVID-19 vaccine found that most complaints concerned systemic reactions. We found reaction differences among vaccine brands, between first and second doses for some effects, and selected recurrent events. Poison control centers are uniquely positioned to conduct post-marketing surveillance for the new vaccines as they are available 24/7 to the public and are healthcare providers. Further post-marketing studies are essential to provide a holistic safety profile of COVID-19 vaccines.

Antibody and T-cell responses 6 months after COVID-19 mRNA-1273 vaccination in patients with chronic kidney disease, on dialysis, or living with a kidney transplant.

BACKGROUND: The immune response to COVID-19 vaccination is inferior in kidney transplant recipients (KTR), and to a lesser extent in patients on dialysis or with chronic kidney disease (CKD). We assessed the immune response 6 months after mRNA-1273 vaccination in kidney patients and compared this to controls. METHODS: 152 participants with CKD stages G4/5 (eGFR <30  mL/min/1.73m2), 145 participants on dialysis, 267 KTR, and 181 controls were included. SARS-CoV-2 Spike S1-specific IgG antibodies were measured by fluorescent bead-based multiplex-immunoassay, neutralizing antibodies to ancestral, Delta and Omicron (BA.1) variants by plaque reduction, and T-cell responses by IFN-γ release assay. RESULTS: At 6 months after vaccination S1-specific antibodies were detected in 100% of controls, 98.7% of CKD G4/5 patients, 95.1% of dialysis patients, and 56.6% of KTR. These figures were comparable to the response rates at 28 days, but antibody levels waned significantly. Neutralization of the ancestral and Delta variant was detected in most participants, whereas neutralization of Omicron was mostly absent. S-specific T-cell responses were detected 6 months in 75.0% of controls, 69.4% of CKD G4/5 patients, 52.6% of dialysis patients, and 12.9% of KTR. T-cell responses at 6 months were significantly lower than responses at 28 days. CONCLUSIONS: Although seropositivity rates at 6 months were comparable to that at 28 days after vaccination, significantly decreased antibody levels and T-cell responses were observed. The combination of low antibody levels, reduced T-cell responses, and absent neutralization of the newly-emerging variants indicates the need for additional boosts or alternative vaccination strategies in KTR.

Emerging heterologous mRNA-based booster strategies within the COVID-19 vaccine landscape.

Messenger RNA (mRNA)-based vaccine platforms used for the development of mRNA-1273 and BNT162b2 have provided a robust adaptable approach to offer protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, as variants of concern (VoCs), such as omicron and associated sub-variants, emerge, boosting strategies must also adapt to keep pace with the changing landscape. Heterologous vaccination regimens involving the administration of booster vaccines different than the primary vaccination series offer a practical, effective, and safe approach to continue to reduce the global burden of coronavirus disease 2019 (COVID-19). To understand the immunogenicity, effectiveness, and safety of heterologous mRNA-based vaccination strategies, relevant clinical and real-world observational studies were identified and summarized. Overall, heterologous boosting strategies with mRNA-based vaccines that are currently available and those in development will play an important global role in protecting individuals from COVID-19 caused by emerging VoCs.

Evolution of anti-SARS-CoV-2 spike protein titers after two-dose of COVID-19 vaccination among people living with HIV.

Background: A community COVID-19 outbreak caused by the B.1.1.7 SARS-CoV-2 variant occurred in Taiwan in May 2021. High-risk populations such as people living with HIV (PLWH) were recommended to receive two doses of COVID-19 vaccines. While SARS-CoV-2 vaccines have demonstrated promising results in general population, real-world information on the serological responses remains limited among PLWH. Methods: PLWH receiving the first dose of SARS-CoV-2 vaccine from 2020 to 2021 were enrolled. Determinations of anti-SARS-CoV-2 spike IgG titers were performed every one to three months, the third dose of the SARS-CoV-2 vaccine or confirmed SARS-CoV-2 infection. All serum samples were tested for anti-nucleocapsid antibody and those tested positive were excluded from analysis. Results: A total of 1189 PLWH were enrolled: 829 (69.7%) receiving two doses of the AZD1222 vaccine, 232 (19.5%) of the mRNA-1273 vaccine, and 128 (10.8%) of the BNT162b2 vaccine. At all time-points, PLWH receiving two doses of mRNA vaccines had consistently higher antibody levels than those receiving the AZD1222 vaccine (p <0.001 for all time-point comparisons). Factors associated with failure to achieve an anti-spike IgG titer >141 BAU/mL within 12 weeks, included type 2 diabetes mellitus (DM) (adjusted odds ratio [aOR], 2.24; 95% CI, 1.25-4), a CD4 T cell count <200 cells/mm3 upon receipt of the first dose of vaccination (aOR, 3.43; 95% CI, 1.31-9) and two homologous AZD1222 vaccinations (aOR, 16.85; 95%CI, 10.13-28). For those receiving two doses of mRNA vaccines, factors associated with failure to achieve an anti-spike IgG titer >899 BAU/mL within 12 weeks were a CD4 T cell count <200 cells/mm3 on first-dose vaccination (aOR, 3.95; 95% CI, 1.08-14.42) and dual BNT162b2 vaccination (aOR, 4.21; 95% CI, 2.57-6.89). Conclusions: Two doses of homologous mRNA vaccination achieved significantly higher serological responses than vaccination with AZD1222 among PLWH. Those with CD4 T cell counts <200 cells/mm3 and DM had consistently lower serological responses.

Enhanced Vaccine Effectiveness during the Delta Phase of the COVID-19 Pandemic in the Medicare Population Supports a Multilayered Prevention Approach.

Throughout the pandemic, individuals 65 years and older have contributed most COVID-19 related deaths. To best formulate effective vaccination and other prevention policies to protect older adults, large scale observational studies of these higher risk individuals are needed. We conducted a Vaccine Effectiveness (VE) study during the B.1.617.2 Delta variant phase of the pandemic in July and August 2021 in a cohort of 17 million Medicare beneficiaries of which 5.7 million were fully vaccinated. We found that individuals fully vaccinated with the Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273 vaccines in January 2021 had 2.5 times higher breakthrough infections and hospitalizations than those fully vaccinated in March 2021, consistent with waning of vaccine-induced immunity. Measuring VE weekly, we found that VE against hospitalization, and even more so against infection, increased from July 2021 through August 2021, suggesting that in addition to the protective role of vaccination, increased masking or social distancing might have contributed to the unexpected increase in VE. Ongoing monitoring of Medicare beneficiaries should be a priority as new variants continue to emerge, and the VE of the new bivalent vaccines remains to be established. This could be accomplished with a large Medicare claims database and the analytics platform used for this study.

Recurrence of Thrombotic Thrombocytopenic Purpura After Vaccination with mRNA-1273 COVID-19 vaccine.

Thrombotic thrombocytopenic purpura (TTP) is a rare disease characterized by thrombocytopenia, microangiopathic hemolytic anemia, and ischemic organ damage. Several cases of TTP associated with administration of COVID-19 vaccines have been reported. We report a case of a 63-year-old woman with a past medical history of hypertension, diabetes mellitus, chronic kidney disease, HIV infection, and remote history of TTP who presented with several days of shortness of breath on exertion, chest tightness, low-grade fever, and bruising thirty-three days after receiving the second dose of the mRNA-1273 COVID-19 vaccine. Thrombocytopenia and hemolytic anemia with schistocytes were noted on testing, and ADAMTS13 activity was <5%. Temporizing treatment with fresh frozen plasma was started immediately on presentation, and treatment was continued with daily therapeutic plasma exchange and corticosteroids. TTP should be considered in patients who present with thrombocytopenia after COVID-19 vaccination, especially if there is a past history of TTP.

Evaluation of Short-Term Symptoms Associated With COVID-19 Vaccines Used Among Adolescents in Saudi Arabia.

OBJECTIVES: Several government-sponsored reporting systems have stated mild to moderate side effects of COVID-19 vaccines. However, patient-reported data on COVID-19 vaccine-associated adverse effects in adolescents are lacking. Our objective was to assess the short-term side effects of Pfizer-BioNTech BNT162b2 or Moderna mRNA-1273 vaccinations among teenagers in Saudi Arabia. METHODS: A retrospective, cross-sectional study was conducted among individuals aged 12-18 years old who received one of the two mentioned vaccines between July 2021 and March 2022 in Riyadh, Saudi Arabia. RESULTS: The most common short-term side effects reported for COVID-19 vaccines among teenagers in our study were fatigue, pain at the site of injection, fever, chills, headache, nausea, and vomiting. Female participants, individuals who had a history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and those who received two doses of the vaccine are at higher risk to develop side effects after getting the vaccine. Importantly, asthmatic participants have a higher incidence of COVID-19 vaccine side effects when compared to those with no history of chronic diseases. CONCLUSION: Our findings might enhance public trust in the COVID-19 vaccine, which could speed up the immunization procedure.

Long-Term Antibody Response against SARS-CoV-2 in Health Care Workers: Effectiveness of Homologous and Heterologous Regimens and Their Relation to Systemic Vaccine-Associated Symptoms.

This prospective study provides data on the long-term humoral immunogenicity of a heterologous off-label vaccine regimen combining the adenoviral-vectored ChAdOx1 nCoV-19 from Astra-Zeneca (ChAd) with the mRNA-1273 vaccine from Moderna (m1273) in comparison with two different homologous mRNA vaccine schedules. Of the 316 COVID-19 naïve adult health care workers (HCW) included to complete a survey on vaccine-associated symptoms (VAS), 197 had received the homologous BNT162b2 mRNA vaccine from Pfizer/BioNTech (BNT/BNT), 76 the homologous m1273/m1273, and 43 the heterologous ChAd/m1273 vaccine regimen. The concentration of antibodies against SARS-CoV-2 spike protein in plasma 5-7 months after the second vaccine dose was higher in the m1273/m1273 and ChAd/m1273 than the BNT/BNT vaccine group. The frequency of systemic VAS after the first vaccine dose was 86% after ChAd compared with 35% and 39% after BNT and m1273, respectively (p < 0.0001), and after the second vaccine dose, the highest (89%) in the m1273/m1273 group (p < 0.001). Individuals with systemic VAS achieved higher levels of antibodies irrespective of vaccine regimen. In conclusion, VAS serve as a strong predictor of long-term humoral immune response, and the heterologous ChAd/m1273 vaccine regimen provides an at least equal long-term humoral immune response compared with the standard vaccine regimens used in Denmark.

Fulminant myocarditis after the first dose of mRNA-1273 vaccination in a patient with previous COVID-19: a case report.

Background: COVID-19 vaccines have shown success in protecting people worldwide, although serious adverse effects have been reported in very rare cases. Case summary: A 32-year-old male with a prior medical history of mild COVID-19 infection developed fulminant myocarditis five days after mRNA-1273 vaccination (first dose), which was confirmed using endomyocardial biopsy. He acutely developed respiratory failure and cardiogenic shock with ventricular tachycardia, but recovered completely with short-term high-dose steroid therapy and mechanical cardiac support, which is the recommended treatment for fulminant lymphocytic myocarditis. Discussion: COVID-19 vaccine-induced myocarditis varies from mild to severe. In the present case, the patient was treated as for fulminant lymphocytic myocarditis and recovered relatively quickly. The mechanism of COVID-19 vaccine-associated myocarditis needs to be urgently investigated.

A Systematic Review of Reported Cases of Immune Thrombocytopenia after COVID-19 Vaccination.

With the recent outbreak of the COVID-19 pandemic and emergency use authorization of anti-SARS-CoV-2 vaccines, reports of post-vaccine immune thrombocytopenia (ITP) have gained attention. With this systematic review, we aim to analyze the clinical characteristics, therapeutic strategies, and outcomes of patients presenting with ITP after receiving COVID-19 vaccination. Medline, Embase, and Ebsco databases were systematically explored from inception until 1 June 2022. Case reports and case series investigating the association between the anti-SARS-CoV-2 vaccine and ITP were included. We found a total of 66 patients. The mean age of presentation was 63 years with a female preponderance (60.6%). Sixteen patients had pre-existing ITP. The mean time from vaccine administration to symptom onset was 8.4 days. More ITP events were triggered by mRNA vaccines (BNT162b2 (n = 29) > mRNA-1273 (n = 13)) than with adenoviral vaccines (ChAdOx1-S AstraZeneca (n = 15) > Ad26.COV2-S (n = 9)). Most of the patients were treated with steroids or IVIG, or both. The overall outcome was promising, with no reported deaths. Our review attempts to increase awareness among physicians while evaluating patients presenting with thrombocytopenia after receiving the vaccine. In our solicited opinion, the rarity of these events and excellent outcomes for patients should not change views regarding the benefits provided by immunization.