Vaccines and allergic reactions: The past, the current COVID-19 pandemic, and future perspectives

Opportunities and Challenges for Nanomaterials as Vaccine Adjuvants

Adjuvants, as a critical component of vaccines, are capable of eliciting more robust and sustained immune responses. Nanomaterials have shown unique advantages and broad application prospects in adjuvant development due to their high adjustability and distinctive physicochemical properties. This review focuses on nanoadjuvants and their immunological mechanisms. First, various types of adjuvants are introduced with an emphasis on metal and metal oxide nanoparticles, coordination polymers, liposomes, polymer nanoparticles, and other inorganic nanoparticles that can serve as vaccine adjuvants. Second, this review describes the current status of the clinical applications of nanoadjuvants. Next, the mechanisms of action for nanoadjuvants have been thoroughly elucidated, including the depot effect, NLRP3 inflammasome activation, targeting C-type lectin receptors, activation of toll-like receptors, and activation of the cGAS-STING signaling pathway. Finally, the challenges and opportunities associated with the development of nanoadjuvants have also been addressed.

Unravelling the complexity of CARPA: a review of emerging advancements in therapeutic strategies

Hypersensitivity reactions to complement activation-related pseudo-allergy (CARPA) pose a serious concern to patient safety when using nanoparticle-based drug delivery systems (NDDS). Complement activation-related pseudo-allergy is a severe, idiosyncratic hypersensitivity reaction consequent to complement activation and liberation of potent pro-inflammatory molecules. Recent developments have concentrated on identifying, managing, and preventing CARPA to improve the efficacy and safety of NDDS, including early identification biomarkers and highly sensitive diagnostic techniques. The development of biocompatible nanoparticles, surface changes to reduce complement activation, and the use of complement inhibitors are some of the innovative strategies for CARPA reduction that are highlighted. Furthermore, newly developed management procedures, such as premedication schedules, customized dosage plans, and real-time monitoring methods, are also covered. The scope of this review encompasses the new diagnostic methods based on in-vitro assays, ex-vivo models, and highly sensitive imaging techniques for the detection of complement activation and other related pseudo-allergic reactions including liposome encapsulation and PEGylation to enhance biocompatibility and decrease immune stimulation. Special emphasis is paid to the application of high-throughput screening technologies and omics tools that enhance the likelihood and evaluation of CARPA immunogenicity. Integration of these approaches forms a comprehensive approach to improving the understanding and administration of CARPA in clinical settings to increase patient safety during nanoparticle-based treatment. The advanced alignments complement regulatory and clinical concerns and connect experimental paradigms to applications, such integration of knowledge provides a platform for the development of next-generation NDDSs for reducing CARPA and enhancing the efficiency of medication delivery thereby increasing patient compliance. This abstract delineates the methods of diagnosing, preventing, and managing CARPA, with addressing the nanotechnology for the problem.

Sex, Age, and Previous Herpes Zoster Infection Role on Adverse Events Following Immunization with Adjuvanted Recombinant Vaccine

Adverse events following immunizations (AEFIs) with recombinant zoster vaccine (RZV) are underexplored in fragile populations. This study aims to assess incidence, duration, and characteristics of AEFIs, focusing on the impact of sex, age, and prior Herpes Zoster (HZ) infection in a frail population, including solid organ transplant recipients. We conducted an observational study on patients receiving RZV, and AEFIs were classified as local or systemic and analyzed for incidence, duration, and patterns across groups. We showed that females had a higher incidence of AEFIs (p = 0.02), both local and systemic symptoms, such as swelling +/- redness at the site of injection and fatigue, after the first and second doses. Younger adults experienced more systemic reactions, while older adults reported more local events (e.g., redness and swelling, p = 0.01). Moreover, patients with previous HZ infection exhibited a higher incidence of AEFIs after the second dose (68% vs. 38%, p = 0.001). In conclusion, sex, age, and clinical history significantly influenced AEFI incidence and manifestations. Therefore, it is important to personalize vaccination strategies in frail populations, by tailored administration and monitoring plans, especially in females and individuals with prior HZ infection, to improve vaccine safety and patient outcomes.

Using the diffusion of innovations theory to understand factors associated with COVID-19 vaccination among tobacco users

The coronavirus disease (COVID-19) pandemic has spread in the US with more than 100 million human infections and a million deaths since March 2020. A population of concern are high-risk individuals such as adults who are tobacco users, since COVID-19 is a respiratory disease that affects the lungs. Although 79% of the US population ≥ 18 years of age have completed the primary COVID-19 vaccine series; it is imperative to understand the factors associated with receiving or declining the COVID-19 vaccine among high-risk populations to improve vaccination rates. Guided by the diffusion of innovations (DOI) theory, this study identified factors associated with COVID-19 vaccination and the impact on COVID-19 vaccine uptake in adults who use tobacco. We conducted a cross-sectional study using a sample of Pennsylvanian adult tobacco users by sending a unique survey link to 4,081 email addresses in April 2022. Participants were asked about tobacco use, COVID-19 vaccination status, and reasons for receiving/declining the COVID-19 vaccine. Participants (n = 157) were 75% female, 96% White, 74% current tobacco users, and had a mean age of 50.1 (SD = 10.8) years. Nearly 78% (n = 119) received at least one dose of the COVID-19 vaccine (primary series). We categorized all vaccinated tobacco users into adopter categories of the DOI theory; innovators (10%), early adopters (14%), early majority (33%), late majority (11%), and laggards (32%). The major reason that prompted participants to get the COVID-19 vaccine was to ensure they were well protected against COVID-19 infection (77%). Additionally, the only reason for receiving the vaccine that significantly predicted early vaccine uptake (being an innovator or early adopter) was "to loosen restrictions on mask mandates and social/physical distancing" (p = 0.0180). Among the 22% that did not receive a COVID-19 vaccine, the most common major reason they declined the vaccine was because they felt politics played a big role in the vaccine development process (94%). Our findings suggest that major f actors that influenced why adult tobacco users would receive or decline the COVID-19 vaccine included infection control mandates, protection from the COVID-19 infection, and politics. Investigating these factors can help public health professionals design or develop future vaccination programs for high-risk populations in order to scale up vaccination rates.

Immunization-related complex regional pain syndrome: A systematic review of case reports

Aim

Vaccines have been shown to have the highest efficacy in preventing infectious diseases through their ability to induce immunological memory against pathogens. An adverse reaction to a vaccine is an unexpected medical occurrence following immunization. Complex regional pain syndrome (CRPS) is a disease that has undergone much controversy regarding its onset post-vaccination. This systematic review aims to evaluate cases of CRPS post-vaccination to better understand the manifestation of the disease and its potential association with vaccines.

Methods

A systematic review of case reports was conducted employing the PRISMA 2020 guidelines. Outcomes of interest include type of vaccination, patient age, patient sex, time to symptom onset, and medical history including but not limited to previous autoimmune diseases, psychological illness, physical tissue trauma, and neurological disease.

Results

Initial querying of the five databases yielded 404 articles. Following a thorough review of articles, only 14 remained, comprising 18 cases. Studies included cases of CRPS development following tetanus, hepatitis B, hepatitis A, rubella, influenza, tetanus-diphtheria, human papillomavirus, and COVID-19 vaccine administration.

Conclusion

The limitations of evidence used in this study highlight the need for a greater output of higher-level evidence in the form of controlled trials and retrospective studies to help further elucidate the connection between vaccine use and the development of CRPS in patients. Currently, vaccines continue to be safe for global public use.

Impact of Comorbidities and Skin Diseases on Post-Vaccination Reactions: A Study on COVID-19 Vaccinations in Poland

Background: The COVID-19 pandemic necessitated rapid and widespread vaccination efforts, which proved critical in reducing the severity and mortality of the virus. However, the interplay between vaccinations, pre-existing skin conditions, and other comorbidities still needs to be explored. This study investigated the occurrence and severity of adverse events following immunization (AEFIs) with COVID-19 vaccines in individuals with chronic skin diseases and comorbidities within a Central European cohort. Methods: An anonymous online survey was conducted between May 2022 and February 2023, targeting students and employees of universities in Wrocław, Poland. A total of 513 respondents were analyzed, focusing on AEFIs following the first, second, and third doses of COVID-19 vaccines and the effects of COVID-19 on conditions such as atopic dermatitis, psoriasis, vitiligo, acne vulgaris, rosacea, and various comorbidities. Results: COVID-19 vaccination effectively protected against severe disease across all doses. The analysis revealed no significant impact of either COVID-19 infection or vaccination on the course of selected skin diseases and comorbidities. The reporting of AEFIs to the Sanitary Inspection was notably low. The Moderna and Pfizer mRNA-based vaccines were associated with a higher reported number of AEFIs, particularly after the second and third doses, compared to AstraZeneca, which exhibited fewer adverse events after subsequent doses. Conclusions: COVID-19 vaccination is both safe and effective, even in patients with pre-existing skin conditions and comorbidities. Vaccine selection may benefit from considering individual health profiles, and better reporting of AEFIs is needed to enhance vaccine safety monitoring.

Safety of COVID-19 Vaccines among People with History of Allergy: A European Active Surveillance Study

Background: Conventional vaccines rarely cause severe allergic reactions. However, the rapid development and approval of COVID-19 vaccines left limited initial data on their adverse reactions, particularly in individuals with a history of allergy. The aim of this study was to assess and compare the safety profile of different doses and brands of COVID-19 vaccines in subjects with a history of allergy vs. those without a history of allergy. Methods: From February 2021 to February 2023, a web-based prospective study gathered vaccinee-reported outcomes using electronic questionnaires across eleven European countries. Baseline and up to six follow-up questionnaires captured data on vaccinee demographics, as well as both solicited and unsolicited adverse reactions. Results: Overall, 3476 vaccinees with a history of allergy were matched with 13,872 vaccinees from the general population at the first vaccination cycle and were included in the analysis. A total of 825 vaccinees with a history of allergy who had received a booster dose, matched to 3297 vaccinees from the general population, were included in the analysis. Higher rates of ADRs occurred after the first vaccination cycle compared to after the booster dose (64-91% vs. 56-79%). However, most reported ADRs were solicited and not serious, and no case of anaphylaxis was reported. Women and vaccinees with a history of allergy reported ADRs more frequently than men and the matched controls, respectively. Compared to other COVID-19 vaccines, a higher proportion of vaccinees experiencing at least one ADR following their first vaccination cycle was observed with Comirnaty and Vaxzevria. Statistically significant differences were observed among the study cohorts for median TTO after the second dose, and for median TTR following the first vaccination cycle and booster dose (p < 0.001). Conclusions: Typically, any drug or vaccine use carries a risk of severe allergic reactions, yet the benefits of vaccination generally outweigh these potential risks, as shown with the COVID-19 vaccines.

Vaccines and allergy: Back to the right places

Hypersensitivity reactions represent one of the most common causes of hesitancy for adherence to national vaccination programs. The majority of hypersensitivity reactions after vaccination are mild, and anaphylaxis is reported to be rare, although it remains challenging to estimate the frequency attributed to each single vaccine, either because of the lower number of administered doses of less common vaccines, or the administration of simultaneous vaccine in most of the vaccination programs. Although literature remains scattered, international consensus guides clinicians in identifying patients who might need the administration of vaccines in protected environments due to demonstrated hypersensitivity to vaccine components or adjuvants. Here we provide the current guidance on hypersensitivity reactions to vaccines and on vaccination of children with allergy disorders.

Nanomedicine Therapies for Pediatric Diseases

In 2020, the top 10 causes of death among children and adolescents between the ages of 1 and 19 years old included cancer, congenital anomalies, heart disease, and chronic respiratory disease; all these conditions are potentially treatable with medical intervention. However, children exhibit specific physiological and developmental characteristics that can significantly impact drug pharmacokinetics, pharmacodynamics, and safety profile. These factors illustrate the importance of a heightened focus on pediatric drug development. Traditional drugs lack proper circulation, permeability, targeting, accumulation, and release, and they often require dose adjustments or modifications, which can result in suboptimal therapeutic outcomes and increased risks of adverse effects in pediatric patients. Nanomedicines have emerged as efficient drug delivery systems because of their unique properties, which can improve the solubility and stability of drugs by encapsulating them in different forms of nanoparticles. This review discusses the challenges of pediatric therapy, and the current state of nanomedicines for pediatric diseases in terms of Food and Drug Administration-approved nanomedicines, the types of diseases treated or diagnosed, and preclinical studies that have the potential to be translated to the clinic. In summary, nanomedicine holds significant potential for addressing the unique and pressing challenges associated with diagnosing and treating pediatric diseases.

No Yellow Fever Vaccine Reactions in IgE-Mediated Egg Allergic Patients

INTRODUCTION

Egg allergy usually manifests during the initial 2 years of life, a period in which most vaccinations are administered. This often leads to delays in the application of some vaccines in patients with egg allergies, exposing them to a risk of contracting preventable infections. The aim of the study was to describe the frequency of reactions after applying the yellow fever vaccine (YFV) within a population with egg allergy.

METHODS

This was a cohort study with retrospective, multicenter data (2014-2023). Patient records diagnosed with egg allergy were gathered from their initial egg-related reactions until their YFV administration. Information was also collected about hypersensitivity tests conducted for egg and YFV such as the skin prick test (SPT) and intradermal test (IDT).

RESULTS

Among the 171 records analyzed, 23.9% of patients had a history of egg anaphylaxis. Out of these, 5 patients had a positive SPT and 21 IDT with the YFV. All patients tolerated the application of YFV without developing hypersensitivity reactions, regardless of the results of the YFV tests, the severity of egg reactions, the number of egg reactions, or the time since the last egg reaction. Out of the total patient cohort, 46.1% (79 individuals) encountered delays in receiving the YFV, and in this subset, 14% faced delays lasting longer than 12 months.

CONCLUSION

The risk of allergic reactions with the YFV remains low. YFV tests generate delays in the vaccine application without providing high diagnostic accuracy. YFV should not be deferred even in patients with a history of severe egg reactions.

An Unexpected Post-Egg-Free Influenza Vaccine Granulomatous Reaction

ABSTRACT

A 53-year-old woman presented with a pruritic plaque on the left upper arm that appeared following an egg-free flu vaccine due to a history of reaction to the standard vaccine. The affected area enlarged over a several month period immediately following vaccine administration. Physical examination revealed an 8 × 4 cm coalescent pink plaque on the left upper arm. A shave biopsy of the lesion showed dermal "naked" granulomas, or granulomas with sparse lymphocytic infiltrate at the margins, as typically seen in sarcoidosis. No foreign material was seen in the granulomatous reaction, including with polarization. Special stains, including acid fast bacilli, Grocott methenamine silver, periodic acid-Schiff, and Gram, were negative for organisms. The diagnosis of granulomatous dermatitis was made. Subsequent imaging demonstrated no findings suggestive of sarcoidosis. While vaccine-associated hypersensitivity reactions occur frequently, these reactions are typically due to individual vaccine components, such as egg protein, and do not normally result in the formulation of granulomas. Vaccination-induced granulomas are more often associated with the use of aluminum as an adjuvant; however, this is not present in the egg-free influenza vaccine. Thus, a granulomatous reaction to the egg-free influenza vaccine is very unusual and, to our knowledge, not previously reported.

Clinical-Epidemiological Profile of COVID-19 Patients Admitted during Three Waves of the Pandemic in a Tertiary Care Center, in Belém, Pará, Amazon Region of Brazil

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a disease with a broad clinical spectrum, which may result in hospitalization in healthcare units, intensive care, and progression to death. This study aimed to describe and compare the clinical and epidemiological profile of COVID-19 during the three waves of the disease, in patients admitted to a public hospital in the city of Belém, Pará, in the Amazon region of Brazil.

METHODS

This descriptive, observational, and cross-sectional study was population-based on individuals who were hospitalized with a diagnosis of COVID-19, confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR), and who were interviewed and monitored at the public hospital, from February 2020 to April 2022.

RESULTS

The prevalence was male patients, older than 60 years. The most frequent symptoms were dyspnea, cough, and fever. Systemic arterial hypertension was the most prevalent comorbidity followed by diabetes mellitus. Less than 15% of patients were vaccinated. The nasal oxygen cannula was the most used oxygen therapy interface followed by the non-rebreathing reservoir mask. Invasive mechanical ventilation predominated and the median time of invasive mechanical ventilation ranged from 2 to 6 days among waves. As for the hospital outcome, transfers prevailed, followed by deaths and discharges.

CONCLUSION

The presence of comorbidities, advanced age, and male sex were important factors in the severity and need for hospitalization of these patients, and the implementation of the vaccination policy was an essential factor in reducing the number of hospital admissions.

Safety and Tolerability of COVID-19 Vaccine in Mast Cell Disorders Real-Life Data from a Single Centre in Italy

Background In the past three years, COVID-19 has had a significant impact on the healthcare systems and people's safety worldwide. Mass vaccinations dramatically improved the health and economic damage caused by SARS-CoV-2. However, the safety of COVID-19 vaccines in patients at high risk of allergic reactions still has many unmet needs that should be clarified. Material and methods A retrospective, single-centre study was performed by collecting demographic and clinical data of patients with Mast Cell Disorders (MCDs) to evaluate the safety and tolerability of COVID-19 vaccinations. Moreover, any changes in the natural history of the underlying disease following the vaccine have been evaluated. Results This study included 66 patients affected with MCDs. Out of them, 52 (78.8%) received a COVID-19 vaccination and 41 (78.8%) completed the vaccination course. Premedication came first in 86.6% of our patients. A total of seven (4.5%) patients complained about an immediate reaction and two (1.3%) had a late reaction. Worsening of MCD history was observed in a single patient. Conclusions Despite the overall high risk of allergic reactions, our study did not reveal any increased risk for SARS-CoV-2 allergic reactions in MCD patients, thus supporting the recommendation in favour of the SARS-CoV-2 vaccination. However, due to the potentially increased rate of anaphylactic reactions, MCD patients should receive vaccine premedication and should be treated in a hospital setting after an allergological specialistic evaluation.

Fair-split distribution of multi-dose vaccines with prioritized age groups and dynamic demand: The case study of COVID-19

The emergence of the SARS-CoV-2 virus and new viral variations with higher transmission and mortality rates have highlighted the urgency to accelerate vaccination to mitigate the morbidity and mortality of the COVID-19 pandemic. For this purpose, this paper formulates a new multi-vaccine, multi-depot location-inventory-routing problem for vaccine distribution. The proposed model addresses a wide variety of vaccination concerns: prioritizing age groups, fair distribution, multi-dose injection, dynamic demand, etc. To solve large-size instances of the model, we employ a Benders decomposition algorithm with a number of acceleration techniques. To monitor the dynamic demand of vaccines, we propose a new adjusted susceptible-infectious-recovered (SIR) epidemiological model, where infected individuals are tested and quarantined. The solution to the optimal control problem dynamically allocates the vaccine demand to reach the endemic equilibrium point. Finally, to illustrate the applicability and performance of the proposed model and solution approach, the paper reports extensive numerical experiments on a real case study of the vaccination campaign in France. The computational results show that the proposed Benders decomposition algorithm is 12 times faster, and its solutions are, on average, 16% better in terms of quality than the Gurobi solver under a limited CPU time. In terms of vaccination strategies, our results suggest that delaying the recommended time interval between doses of injection by a factor of 1.5 reduces the unmet demand up to 50%. Furthermore, we observed that the mortality is a convex function of fairness and an appropriate level of fairness should be adapted through the vaccination.

[Experiencia en la vacunación frente a la COVID-19 en personas con antecedentes de alergia.]

OBJECTIVE

A common consultation since the beginning of the vaccination campaign against COVID-19 was related to people with a history of allergy to drugs or other vaccines. The objective of the study was to describe what happened after the administration of the vaccine against COVID-19 in people with a history of moderate and severe allergy, vaccinated against COVID-19 in a Primary Care Emergency Center (PCEC).

METHODS

Observational descriptive study with sixty-four people with a history of moderate and severe allergy was carried out, vaccinated in PCEP, between May and October 2021, in the Barcelonés Nord and Maresme (Barcelona province), after assessment by primary care pharmacologists and pharmacists. The percentage of people with adverse events that occurred after vaccination during their stay in the PCEP, the types detected and severity were calculated. Subsequently, a telephone survey was conducted to determine patient satisfaction. A descriptive analysis (calculation of proportions) was performed.

RESULTS

The mean age of 49.7 years (from twelve to ninety-four years) and 90.6% were women. 87.5% of the administered vaccines were Comirnaty®. Adverse events occurring after vaccination were detected in fifteen patients (23.4%), of whom four (6.25%) were manifestations of hypersensitivity, all classified as mild. The reasons for vaccination were a history of allergy to NSAIDs (45.3%), antibiotics (32.8%), analgesics (17.2%), vaccines (28.1%), other substances (40.6%) and anaphylaxis (26.6%). The degree of general satisfaction was 9.11 (out of 10).

CONCLUSIONS

The percentage of patients with a history of anaphylaxis and allergic drug reactions who present hypersensitivity reactions to COVID-19 vaccines is 6.25% and all are mild.

Evaluation of Children with Cow's Milk Allergy Who Received Measles or Measles, Mumps, and Rubella Vaccines Containing Alpha-Lactalbumin

Objective: Cases of cow's milk allergy (CMA) who reacted to measles or measles, mumps, and rubella (MMR) vaccines containing alpha-lactalbumin have been reported. The purpose of this study was to assess patients with CMA who received measles or MMR vaccines containing alpha-lactalbumin, as well as the characteristics of those who developed reactions to these vaccines. Study Design: Patients followed up in the allergy clinic for CMA and who received measles or MMR vaccines containing alpha-lactalbumin at 9 or 12 months of age were included in the study, and their characteristics were analyzed retrospectively from the hospital registry system. Results: Forty-nine patients were included in the study. Six patients received the measles vaccine, whereas 43 patients received the MMR vaccine containing alpha-lactalbumin. Vaccine skin tests were performed on these 6 patients. One patient had a positive intradermal test, so an alternative vaccine not containing alpha-lactalbumin was administered. The other 5 patients were vaccinated, and no reaction was observed. Anaphylaxis was observed in 3 of 43 patients who received the MMR vaccine containing alpha-lactalbumin. In all of these patients, the first reaction to dairy products was anaphylaxis. In 2 of those patients, cow's milk-specific IgE (spIgE) levels were >100 kU/L, and alpha-lactalbumin-spIgE levels were also high at 97 and 90 kU/L. The third patient's cow's milk-spIgE level was 15.9 kU/L, whereas the alpha-lactalbumin-spIgE level was 0.04 kU/L. Conclusion: Especially in patients with an initial reaction of anaphylaxis to dairy products and high cow's milk-spIgE levels, the risk of reaction is high with the MMR vaccine.

Identifying and Managing Those at Risk for Vaccine-Related Allergy and Anaphylaxis

Immediate hypersensitivity reactions to vaccines, the most severe of which is anaphylaxis, are uncommon events occurring in fewer than 1 in a million doses administered. These reactions are infrequently immunoglobulin E-mediated. Because they are unlikely to recur, a reaction to a single dose of a vaccine is rarely a contraindication to redosing. This narrative review article contextualizes the recent knowledge we have gained from the coronavirus 2019 (COVID-19) pandemic rollout of the new mRNA platform with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines within the much broader context of what is known about immediate reactions to other vaccinations of routine and global importance. We focus on what is known about evidence-based approaches to diagnosis and management and what is new in our understanding of mechanisms of immediate vaccine reactions. Specifically, we review the epidemiology of immediate hypersensitivity vaccine reactions, differential diagnosis for immune-mediated and nonimmune reaction clinical phenotypes, including how to recognize immunization stress-related responses. In addition, we highlight what is known about mechanisms and review the rare but important contribution of excipient allergies and specifically when to consider testing for them as well as other key features that contribute to safe evaluation and management.

Anaphylatoxin Complement 5a in Pfizer BNT162b2-Induced Immediate-Type Vaccine Hypersensitivity Reactions

The underlying immunological mechanisms of immediate-type hypersensitivity reactions (HSR) to COVID-19 vaccines are poorly understood. We investigate the mechanisms of immediate-type hypersensitivity reactions to the Pfizer BNT162b2 vaccine and the response of antibodies to the polyethylene glycol (PEG)ylated lipid nanoparticle after two doses of vaccination. Sixty-seven participants, median age 35 and 77.3% females who tolerated two doses of the BNT162b2 vaccine (non-reactors), were subjected to various blood-sampling time points. A separate group of vaccine reactors (10 anaphylaxis and 37 anonymised tryptase samples) were recruited for blood sampling. Immunoglobulin (Ig)G, IgM and IgE antibodies to the BNT162b2 vaccine, biomarkers associated with allergic reaction, including tryptase for anaphylaxis, complement 5a(C5a), intercellular adhesion molecule 1 (ICAM-1) for endothelial activation and Interleukin (IL)-4, IL-10, IL-33, tumour necrosis factor (TNF) and monocyte chemoattractant protein (MCP-1), were measured. Basophil activation test (BAT) was performed in BNT162b2-induced anaphylaxis patients by flow cytometry. The majority of patients with immediate-type BNT162b2 vaccine HSR demonstrated raised C5a and Th2-related cytokines but normal tryptase levels during the acute reaction, together with significantly higher levels of IgM antibodies to the BNT162b2 vaccine (IgM 67.2 (median) vs. 23.9 AU/mL, p < 0.001) and ICAM-1 when compared to non-reactor controls. No detectable IgE antibodies to the BNT162b2 vaccine were found in these patients. The basophil activation tests by flow cytometry to the Pfizer vaccine, 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol (DMG-PEG) and PEG-2000 were negative in four anaphylaxis patients. Acute hypersensitivity reactions post BNT162b2 vaccination suggest pseudo-allergic reactions via the activation of anaphylatoxins C5a and are independent of IgE-mechanisms. Vaccine reactors have significantly higher levels of anti-BNT162b2 IgM although its precise role remains unclear.

Characteristics of immune response profile in patients with immediate allergic and autoimmune urticarial reactions induced by SARS-CoV-2 vaccines

Severe allergic reactions following SARS-COV-2 vaccination are generally rare, but the reactions are increasingly reported. Some patients may develop prolonged urticarial reactions following SARS-COV-2 vaccination. Herein, we investigated the risk factors and immune mechanisms for patients with SARS-COV-2 vaccines-induced immediate allergy and chronic urticaria (CU). We prospectively recruited and analyzed 129 patients with SARS-COV-2 vaccine-induced immediate allergic and urticarial reactions as well as 115 SARS-COV-2 vaccines-tolerant individuals from multiple medical centers during 2021-2022. The clinical manifestations included acute urticaria, anaphylaxis, and delayed to chronic urticaria developed after SARS-COV-2 vaccinations. The serum levels of histamine, IL-2, IL-4, IL-6, IL-8, IL-17 A, TARC, and PARC were significantly elevated in allergic patients comparing to tolerant subjects (P-values = 4.5 × 10^-5-0.039). Ex vivo basophil revealed that basophils from allergic patients could be significantly activated by SARS-COV-2 vaccine excipients (polyethylene glycol 2000 and polysorbate 80) or spike protein (P-values from 3.5 × 10^-4 to 0.043). Further BAT study stimulated by patients' autoserum showed positive in 81.3% of patients with CU induced by SARS-COV-2 vaccination (P = 4.2 × 10^-13), and the reactions could be attenuated by anti-IgE antibody. Autoantibodies screening also identified the significantly increased of IgE-anti-IL-24, IgG-anti-FcεRI, IgG-anti-thyroid peroxidase (TPO), and IgG-anti-thyroid-related proteins in SARS-COV-2 vaccines-induced CU patients comparing to SARS-COV-2 vaccines-tolerant controls (P-values = 4.6 × 10^-10-0.048). Some patients with SARS-COV-2 vaccines-induced recalcitrant CU patients could be successfully treated with anti-IgE therapy. In conclusion, our results revealed that multiple vaccine components, inflammatory cytokines, and autoreactive IgG/IgE antibodies contribute to SARS-COV-2 vaccine-induced immediate allergic and autoimmune urticarial reactions.

Anaphylactic Reactions to COVID-19 Vaccines: An Updated Assessment Based on Pharmacovigilance Data

This study aimed at producing an updated assessment of the incidence of anaphylaxis associated with COVID-19 vaccines based on pharmacovigilance data. Anaphylactic reaction and anaphylactic shock data post-COVID-19-vaccination reported from week 52, 2020 to week 1 or week 2, 2023 were collected from the VAERS and EudraVigilance databases, respectively, and analyzed comparatively. Incidence rates were calculated using the corresponding administered vaccine doses as denominators for all licensed vaccines and both platform types (mRNA or vectored). The latest data from the present analysis showed lower anaphylaxis incidence associated with COVID-19 vaccination compared to previous estimates from week 52, 2020 to week 39, 2021 (anaphylactic reaction: 8.96 (95% CI 8.80-9.11)/million doses overall (EEA: 14.19 (95% CI 13.92-14.47)/million/US: 3.17 (95% CI 3.03-3.31)/million); anaphylactic shock: 1.46 (95% CI 1.39-1.52)/million doses overall (EEA: 2.47 (95% CI 2.36-2.58)/million/US: 0.33 (95% CI 0.29-0.38)/million)). Incidence rates varied by vaccine and were higher as captured in EudraVigilance compared to the VAERS and for vectored compared to mRNA vaccines. Most reported cases had a favorable outcome. The extremely rare fatalities (overall rates across continents 0.04 (95% CI 0.03-0.06)/million doses for anaphylactic reaction and 0.02 (95% CI 0.01-0.03)/million vaccine doses for anaphylactic shock) were also associated with vector-rather than mRNA-based vaccines. The diminished incidence of anaphylaxis post-vaccination with COVID-19 vaccines offers assurance about their safety, as does the continuous potential adverse events monitoring through specialized pharmacovigilance databases.

Design of lipid-based nanoparticles for delivery of therapeutic nucleic acids

The successful development of nonviral delivery systems for nucleic acids has been reported extensively over the past number of years. Among them, lipid-based nanoparticles (LNPs) represent the most advanced platform. This review provides an overview of the state-of-the-art in LNP technology, focusing on the delivery of a range of nucleic acids. Recent advances in the development of an efficient and safe lipid-based system are critically analyzed with a particular emphasis on the rationale behind the design of LNPs and on attempts to elucidate the resulting molecular assembly and structure, their interactions with cellular proteins and biodistribution. In addition, manufacturing methods including microfluidics and their potential to influence stability and scale-up are summarized.

Heart Rate Variability in Subjects with Severe Allergic Background Undergoing COVID-19 Vaccination

Anti-Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccination is the world’s most important strategy for stopping the pandemic. Vaccination challenges the body’s immune response and can be complicated by hypersensitivity reactions. The autonomic nervous system can modulate the inflammatory immune response, therefore constituting a potential marker to characterize individuals at high risk of hypersensitivity reactions. Autonomic nervous system functionality was assessed through measurement of the heart rate variability (HRV) in subjects with a history of severe allergic reactions and 12 control subjects. HRV parameters included the mean electrocardiograph RR interval and the standard deviation of all normal R–R intervals (SDNN). All measurements were performed immediately before the anti-SARS-CoV-2 vaccination. The median RR variability was lower in the study than in the control group: 687 ms (645–759) vs. 821 ms (759–902); p = 0.02. The SDNN was lower in the study group than in the control group: 32 ms (23–36) vs. 50 ms (43–55); p < 0.01. No correlation was found between age and the SDNN. Autonomic nervous system activity is unbalanced in people with a severe allergy background.

Anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents: Analysis of data reported to EudraVigilance

AIM

The present study aimed to estimate the anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents in Europe.

METHODS

We retrieved data on 371 anaphylaxis cases following mRNA COVID-19 vaccination in children ≤ 17 years old notified to EudraVigilance as of October 8, 2022. Overall, 27,120,512 doses of BNT162b2 vaccine and 1,400,300 doses of mRNA-1273 vaccine have been delivered to children during the study period.

RESULTS

The overall mean anaphylaxis rate was 12.81 [95% confidence interval (CI): 11.49-14.12] per 10⁶ mRNA vaccine doses [12.14 (95% CI: 6.37-17.91) per 10⁶ doses for mRNA-1273 and 12.84 (95% CI: 11.49-14.19) per 10⁶ doses for BNT162b2]. Children 12-17 years old accounted for 317 anaphylaxis cases, followed by 48 cases in children 3-11 years old, and 6 cases in children 0-2 years old. Children 10-17 years old had a mean anaphylaxis rate of 13.52 (95% CI: 12.03-15.00) cases per 10⁶ mRNA vaccine doses and children 5-9 years old had a mean anaphylaxis rate of 9.51 (95% CI: 6.82-12.20) cases per 10⁶ mRNA vaccine doses. There were two fatalities, both in the 12-17 years age group. The fatal anaphylaxis rate was 0.07 cases per 10⁶ mRNA vaccine doses.

CONCLUSIONS

Anaphylaxis is a rare adverse event after receiving an mRNA COVID-19 vaccine in children. Continuous surveillance of serious adverse events is needed to guide vaccination policies as we move towards SARS-CoV-2 endemicity. Larger real-world studies on COVID-19 vaccination in children, using clinical case confirmation, are imperative.

New-age vaccine adjuvants, their development, and future perspective

In the present scenario, immunization is of utmost importance as it keeps us safe and protects us from infectious agents. Despite the great success in the field of vaccinology, there is a need to not only develop safe and ideal vaccines to fight deadly infections but also improve the quality of existing vaccines in terms of partial or inconsistent protection. Generally, subunit vaccines are known to be safe in nature, but they are mostly found to be incapable of generating the optimum immune response. Hence, there is a great possibility of improving the potential of a vaccine in formulation with novel adjuvants, which can effectively impart superior immunity. The vaccine(s) in formulation with novel adjuvants may also be helpful in fighting pathogens of high antigenic diversity. However, due to the limitations of safety and toxicity, very few human-compatible adjuvants have been approved. In this review, we mainly focus on the need for new and improved vaccines; the definition of and the need for adjuvants; the characteristics and mechanisms of human-compatible adjuvants; the current status of vaccine adjuvants, mucosal vaccine adjuvants, and adjuvants in clinical development; and future directions.

Increasing the COVID-19 immunization rate through allergy testing

BACKGROUND

Vaccination of the population is required to combat the COVID-19 pandemic. Allergy testing could reduce anxiety towards COVID-19 vaccination and thereby may increase vaccination rate, however, its effectiveness remains unclear.

METHODS

One hundred and thirty prospective real-life patients in need of but not daring to get vaccinated asked for allergy workup for COVID-19 vaccine hypersensitivity in 2021/2022. Characterization of patients, identification of anxieties, decrease of patient's anxiety levels, overall vaccination rate and adverse reactions after vaccination were assessed.

RESULTS

Tested patients were characterized by being female (91.5%) and having a high rate of previous allergies (e.g. to food 55.4%, drugs 54.6%, or previous vaccinations 50%) and dermatological disease (29.2%) but not always had medical contraindications for COVID-19 vaccination. Sixty one patients (49.6%) were highly concerned (4-6, Likert scale 0-6) about vaccination and 47 (37.6%) expressed resolving thoughts about vaccinaion anaphylaxis (3-6, Likert scale 0-6). However only 35 patients (28.5%) were scared of getting COVID-19 within 2 months (4-6, Likert scale 0-6) and only 11 (9%) patients had high expectations of getting COVID-19 (4-6, Likert scale 0-6). Allergy testing significantly (p < 0.01 to p < 0.05 respectively) reduced the median anxiety of allergic symptoms following vaccination: dyspnoea (4.2-3.1), to faint (3.7-2.7), long-term consequences (3.6-2.2), pruritus (3.4-2.6), skin rash (3.3-2.6) and death (3.2-2.6). After allergy testing, most patients (108/122, 88.5%) let themselves be vaccinated within 60 days. Revaccinated patients with previous symptoms experienced a reduction of symptoms (p < 0.05) upon revaccination.

CONCLUSIONS

Patients not daring to get vaccinated have more anxiety towards vaccination than to acquire COVID-19. For those, allergy testing excludes vaccine allergy, and is a tool to increase vaccination willingness and thereby helps to combat vaccination hesitancy.

Allergic Reactions to Vaccines in Children: From Constituents to Specific Vaccines

Vaccination is an essential public health measure that helps to reduce the burden of infectious diseases in children. Although vaccines have an excellent safety record and the association of severe allergic reactions is rare, public concerns about vaccine safety can lead to incomplete vaccination coverage in children with or without allergies. Therefore, it is important to understand the mechanisms and implications of allergic reactions to vaccines and define strategies to manage them to provide the safest care for vaccine recipients. In this review, we provide an overview on the types of allergic reactions that can occur after vaccination, including those caused by various vaccine constituents. We also discuss the mechanisms underlying these allergic reactions and the recommended diagnosis and management strategies for children with a history of suspected allergic reactions to vaccines. An improved understanding of allergic reactions to vaccines can aid in the enhancement of the safety and effectiveness of vaccination.

Self-Reported Allergic Adverse Events Following Inactivated SARS-CoV-2 Vaccine (TURKOVAC™) among General and High-Risk Population

TURKOVAC™ is a whole-virion inactivated COVID-19 vaccine which was developed and granted emergency use and conditional marketing authorization in December 2021 in Türkiye. The objective of this study is to assess the distribution and the severity of allergic adverse events following the administration of the vaccine as the primary or the booster dose in 15 provinces in Türkiye. In this cohort study, between February and May 2022, in the selected 15 provinces having an adequate number of health care personnel in the community health centers to conduct the study, 32,300 people having the first, the second, or the booster dose of the vaccine were invited to the survey. A total of 29,584 people voluntarily agreed to participate to the survey and were given a structured questionnaire after a minimum of 10 days following the vaccination. In our study, only 0.5% of the participants (142 persons) reported to experience any allergic reaction, and 12 of them (8.5%) reported to be given medical treatment in a health center. Male predominance (55.6%) was observed among participants reported to experience any allergic reaction. No hospitalization was recorded. Of the participants, 4.4% (1315 people) reported to have a history of allergy. The most reported allergens were drugs. Among the participants without a known history of allergy (n = 28,269), 0.4% of them (110 people) reported to experience an allergic reaction following the vaccination, and 5.4% of the allergic reactions (six people) were reported to be treated in a health center. The percentage of the participants given any medical treatment among the participants without a known history of allergy is 0.02%. No immediate or anaphylactic reaction was reported. Among the participants with a known history of allergy (n = 1315), 32 people (2.4% of them) reported to experience an allergic reaction following the vaccination, and 18.7% of the allergic reactions (six people) were reported to be prescribed a medical treatment. The percentage of the participants given any medical treatment among the participants with a known history of allergy is 0.4%. A known history of allergy increased the risk of having an allergic experience by approximately six times following vaccination. As a whole-virion inactivated SARS-CoV-2 vaccine, the TURKOVAC™ vaccine, with a low allergic reaction-related adverse event profile, can be an alternative to other COVID-19 vaccines.

A PEG-lipid-free COVID-19 mRNA vaccine triggers robust immune responses in mice

COVID-19 mRNA vaccines represent a completely new category of vaccines and play a crucial role in controlling the COVID-19 pandemic. In this study, we have developed a PEG-lipid-free two-component mRNA vaccine (PFTCmvac) by formulating mRNA encoding the receptor binding domain (RBD) of SARS-CoV-2 into lipid-like nanoassemblies. Without using polyethylene glycol (PEG)-lipids, the self-assembled PFTCmvac forms thermostable nanoassemblies and exhibits a dose-dependent cellular uptake and membrane disruption, eventually leading to high-level protein expression in both mammalian cells and mice. Vaccination with PFTCmvac elicits strong humoral and cellular responses in mice, without evidence of significant adverse reactions. In addition, the vaccine platform does not trigger complement activation in human serum, even at a high serum concentration. Collectively, the PEG-lipid-free two-component nanoassemblies provide an alternative delivery technology for COVID-19 mRNA vaccines and opportunities for the rapid production of new mRNA vaccines against emerging infectious diseases.

The percentage of hesitation and factors associated with acceptance or refusal for COVID-19 vaccine: Does training about vaccines by allergist affect personal decision?

Background and aim

As the impact of coronavirus disease (COVID)-19 arises worldwide, the effect of vaccines is protecting its importance. The aim of this study was to investigate the vaccination perspectives of patients and learn how many patients were persuaded to get vaccinated with the effect of the education provided by allergists.

Materials and methods

A cross-sectional study was carried out among 200 adult patients in the outpatient clinic between February 2021 and January 2022. Patients filled out the anti-vaccination scale form and a questionnaire form developed by allergists. The training about COVID-19 vaccines has been given to the patients who did not consider getting vaccinated. The patients were called by phone and questioned whether they have been vaccinated or not, after 22 weeks.

Results

Out of 200 patients participants, 60.5% were considering getting vaccinated. Patients who did not consider getting vaccinated comprised 45.7% of women and 31% of men. While 52.4% of primary school graduates considered getting vaccinated, 75% of high school graduates and 60.8% of higher education graduates were considering getting vaccinated. Major reasons for rejecting vaccination were concerns about side effects and allergy. While the majority of women (47.2%) who did not want to get vaccinated were concerned about vaccine side effects, the majority of men (34.6%) did not want to get vaccinated because they did not trust the efficacy of the vaccine. Vaccination rates have been increased with the training we provided to our patients who did not consider getting the vaccine. 76 patients could be reached by phone and 81.6% of them were vaccinated, and 18.4% were not.

Conclusion

The vaccination rates of allergy patients who did not consider getting vaccinated were increased with the information provided by allergists. So, the allergists should give more attention for giving information and increasing the vaccination rates of covid-19.

Death and Disability Reported with Cases of Vaccine Anaphylaxis Stratified by Administration Setting: An Analysis of the Vaccine Adverse Event Reporting System from 2017 to 2022

The serious nature of post-vaccination anaphylaxis requires healthcare professionals to be adequately trained to respond to these hypersensitivity emergencies. The aim of this study was to compare outcomes reported with cases of vaccine anaphylaxis stratified by administration setting. We queried reports in the Vaccine Adverse Event Reporting System (VAERS) database from 2017 to 2022 and identified cases involving anaphylaxis with an onset within one day of vaccine administration. The primary outcome was the combined prevalence of death or disability for each setting while the secondary outcome was the prevalence of hospitalization. Adjusted (age, sex, prior history of allergy, vaccine type) odds ratios (aOR) and associated 95% confidence intervals (CI) were calculated using logistic regression analysis. A total of 2041 cases of anaphylaxis comprised the primary study cohort with representation in the sample from all 50 US states and the District of Columbia. The mean age was 43.3 ± 17.5 years, and most cases involved women (79.9%). Cases of anaphylaxis were reported after receiving a coronavirus vaccine (85.2%), influenza vaccine (5.9%), tetanus vaccine (2.2%), zoster vaccine (1.6%), measles vaccine (0.7%), and other vaccine (4.5%). Outcomes associated with reports of vaccine anaphylaxis included 35 cases of death and disability and 219 hospitalizations. Compared with all other settings, the aOR of death and disability when anaphylaxis occurred was 1.92 (95% CI, 0.86-4.54) in a medical provider's office, 0.85 (95% CI, 0.26-2.43) in a pharmacy and 1.01 (95% CI, 0.15-3.94) in a public health clinic. Compared with all other settings, the aOR of hospitalization when anaphylaxis occurred was 1.02 (95% CI, 0.71-1.47) in a medical provider's office, 1.06 (95% CI, 0.72-1.54) in a pharmacy, and 1.12 (95% CI, 0.61-1.93) in a public health clinic. An analysis of a national database across six years revealed no significant differences in the odds of death/disability and odds of hospitalization associated with post-vaccination anaphylaxis in the medical office, pharmacy, and public health clinic compared with all other settings. This study expands our understanding of the safety of immunization services and reinforces that all settings must be prepared to respond to such an emergency.

Skin Testing and Basophil Activation Testing Is Useful for Assessing Immediate Reactions to Polyethylene Glycol-Containing Vaccines

BACKGROUND

The mechanism of immediate reactions to drugs or vaccines containing polyethylene glycol (PEG) and PEG derivatives is not fully elucidated. It is considered in many instances to be IgE-mediated. Diagnosis and management of PEG allergy is topical, as BNT162b and mRNA-1273 contain PEG (2[PEG-2000]-N), and ChAdOx1-S and NVX-CoV2373 contain polysorbate 80. mRNA vaccines contain PEG 2000, which encapsulates the mRNA to impair its degradation. This PEG MW is specific to mRNA vaccines and is not used in other drugs and vaccines. PEG 2000 allergy is not well studied, as higher PEG molecular weights are implicated in most of the PEG allergy published in the literature.

METHODS

We performed a literature review on PEG allergy and sought to evaluate the safety and effectiveness of our protocol for assessment of PEG 2000 and polysorbate 80 reactions in an outpatient clinic setting. All patients referred to our drug allergy service between 1 July 2021 and 31 December 2021 with suspected immediate allergy to PEG or its derivatives were eligible for the study. Skin testing (ST) and basophil activation testing (BAT) were performed for all patients to multiple PEG molecular weights (MWs).

RESULTS

We reviewed twenty patients during the study period. Five patients were allergic. Fifteen patients had a masquerade of allergy and were enrolled as control patients. PEG 2000, polysorbate 80, BNT162b, and ChAdOx1-S had excellent performance characteristics on skin testing. BAT showed high specificity for all vaccines and PEG MWs.

DISCUSSION

In our small study, we found ST and BAT to add useful information, particularly for PEG 2000 allergy. Further study of our protocol in larger patient cohorts will provide more information on its performance characteristics and usefulness.

COVID-19 vaccines adverse events: potential molecular mechanisms

COVID-19 is an infectious disease caused by a single-stranded RNA (ssRNA) virus, known as SARS-CoV-2. The disease, since its first outbreak in Wuhan, China, in December 2019, has led to a global pandemic. The pharmaceutical industry has developed several vaccines, of different vector technologies, against the virus. Of note, among these vaccines, seven have been fully approved by WHO. However, despite the benefits of COVID-19 vaccination, some rare adverse effects have been reported and have been associated with the use of the vaccines developed against SARS-CoV-2, especially those based on mRNA and non-replicating viral vector technology. Rare adverse events reported include allergic and anaphylactic reactions, thrombosis and thrombocytopenia, myocarditis, Bell's palsy, transient myelitis, Guillen-Barre syndrome, recurrences of herpes-zoster, autoimmunity flares, epilepsy, and tachycardia. In this review, we discuss the potential molecular mechanisms leading to these rare adverse events of interest and we also attempt an association with the various vaccine components and platforms. A better understanding of the underlying mechanisms, according to which the vaccines cause side effects, in conjunction with the identification of the vaccine components and/or platforms that are responsible for these reactions, in terms of pharmacovigilance, could probably enable the improvement of future vaccines against COVID-19 and/or even other pathological conditions.

Allergic adverse events following immunization: Data from post-marketing surveillance in Apulia region (South of Italy)

Introduction

Among adverse events following immunization (AEFIs), allergic reactions elicit the most concern, as they are often unpredictable and can be life-threatening. Their estimates range from one in 1,000,000 to one in 50,000 vaccine doses. This report describes allergic events following immunization reported from 2020 to 2021 in Puglia, a region in the South-East of Italy with around 4 million inhabitants. Its main objective is to describe the allergic safety profile of currently employed vaccines.

Materials and methods

This is a retrospective observational study. The study period spanned from January 2020 to December 2021, and the whole Apulian population was included in the study. Information regarding AEFIs reported in Puglia during the study period was gathered from the Italian Drug Authority's pharmacovigilance database (National Pharmacovigilance Network, RNF). The overall number of vaccine doses administered was extrapolated by the Apulian online immunization database (GIAVA). Reporting rates were calculated as AEFIs reported during a certain time span/number of vaccine doses administered during the same period.

Results

10,834,913 vaccine doses were administered during the study period and 95 reports of allergic AEFIs were submitted to the RNF (reporting rate 0.88/100,000 doses). 27.4% of the reported events (26/95) were classified as serious (reporting rate 0.24/100,000 doses). 68 out of 95 (71.6%) adverse events were at least partially resolved by the time of reporting and none of them resulted in the subject's death.

Conclusions

Allergic reactions following vaccination were rare events, thus confirming the favourable risks/benefits ratio for currently marketed vaccines.

Evaluation of the immunotoxicity and allergenicity of a new intranasal influenza vector vaccine against tuberculosis carrying TB10.4 and HspX antigens

Objectives

A new vaccine candidate TB/FLU-05E has been developed at the Smorodintsev Research Institute of Influenza (Russia). The vaccine is based on the attenuated influenza strain A/PR8/NS124-TB10.4-2A-HspX that expresses mycobacterial antigens TB10.4 and HspX. This article describes the results of preclinical immunotoxicity and allergenicity studies of the new vector vaccine TB/FLU-05E against tuberculosis.

Materials and Methods

The experiments were conducted on male CBA mice, С57/black/6 mice, and guinea pigs. The vaccine candidate was administered intranasally (7.7 lg TCID₅₀/animal and 8.0 lg TCID₅₀/animal) twice at a 21-day interval. The immunotoxic properties of the vaccine were assessed in mice according to the following parameters: spleen and thymus weight and their organ-to-body weight ratio, splenic and thymic cellularity, hemagglutination titer assay, delayed-type hypersensitivity test, and phagocytic activity of peritoneal macrophages. Histological examination of the thymus and spleen and white blood cell counts were also performed. Allergenicity of the vaccine was assessed in guinea pigs using conjunctival and general anaphylaxis reaction tests.

Results

The results showed that double immunization with the TB/FLU-05E vaccine did not affect the phagocytic activity of peritoneal macrophages, cellular and humoral immunity after immunization with a heterologous antigen (sheep red blood cells), or the organ-to-body weight ratio of immunocompetent organs (thymus and spleen). The vaccine candidate demonstrated no allergenic properties.

Conclusion

According to the results of this study, the TB/FLU-05E vaccine is well-tolerated by the immune system and demonstrates no immunotoxicity or allergenicity.

Long-term adverse events of three COVID-19 vaccines as reported by vaccinated physicians and dentists, a study from Jordan and Saudi Arabia

Assessment of safety of COVID-19 vaccines is an ongoing process. This study aims to explore long-term adverse events reported by physicians and dentists who received at least two COVID-19 vaccine doses. A group of physicians and dentists were invited to complete a validated questionnaire that was composed of items on: socio-demographics, medical history, administered vaccines, and long-term adverse events (LTAE). Data of a total of 498 practitioners were included. Age ranged from 22 to 71 years (mean age= 35.75 ± 11.74) with a female majority (N = 348, 69.9%). The most frequently administered vaccines were Pfizer-BioNtech, Sinopharm and AstraZeneca vaccines. A total of 80 (16.0%) participants reported LTAEs which were mainly fatigue, menstrual disturbances, myalgia, arthralgia, dizziness, and headache (N = 32, 15, 8, 6, 4, and 4, respectively). There was no statistically significant association between LTAEs and: age, gender, or medical history (P > .05). The collective symptoms of fatigue, myalgia, arthralgia, dizziness, and headache were significantly associated with Sinopharm vaccine (P = .04). This was further confirmed by general linear multivariate model analysis. Less than 20% of COVID-19 vaccine recipients may complain of LTAEs that are mostly fatigue-related. It seems that factors such as age, gender, and medical status play a negligible role in development of these AEs. On the other hand, Sinopharm vaccine showed the highest significant association with these AEs followed by AstraZeneca vaccine.

Impact of Sex and Age on mRNA COVID-19 Vaccine-Related Side Effects in Japan

mRNA COVID-19 vaccination was initiated worldwide in late 2020, and its efficacy has been well reported. However, studies about vaccine-related side effects are sparse. A total of 262 health care workers who received mRNA COVID-19 vaccine BNT162b2 were recruited, and their vaccine-related side effects were investigated. Impact of sex and age on the side effects was statistically analyzed. A higher number of vaccine-related side effects among females versus males was identified (median 3 versus 2, P < 0.05, after the first dose, and 5 versus 2.5, P < 0.01, after the second dose). General fatigue, headache, chills, and fever were the culprit adverse symptoms. In multivariate analysis, females had an increasing number of side effects after receiving their first (B = 0.7; 95% confidence interval [CI], 0.2 to 1.2) and second (B = 1.5; 95% CI, 0.7 to 2.2) vaccine doses compared to that of males. In age analysis, the older group (≥60 years old) had a lower number of side effects than the younger group (B = -0.5 with a 95% CI of -1.1 to -0.02 after the first vaccine dose, and B = -2.1 with a 95% CI of -2.9 to -1.2 after the second vaccine dose). Additionally, prolonged time to recovery was found among females (P = 0.003 after the first dose; P = 0.008 after the second dose). Specifically, symptoms of general fatigue, headache, itching, swelling at the injection site, and dizziness were the culprit symptoms affecting recovery time. Several cutaneous and membranous symptoms, including "COVID arm," were identified among females. These results highlight the impact of sex and age on side effects from mRNA COVID-19 vaccine and will aid in creating a safer vaccine. IMPORTANCE We demonstrate sex- and age-related impact on mRNA COVID-19 vaccine-related side effects, with a higher number and frequency of side effects and prolonged time to recovery in females compared to males and negative correlation between age and vaccine-related side effects. Identification of unique age- and sex-specific adverse symptoms will provide the opportunity to better understand the nature of sex- and age-associated immunological differences and develop safer and more efficacious vaccines.

Optic disc hemorrhage in a young female following mRNA coronavirus disease 2019 vaccination: a case report

BACKGROUND

Since the development of the coronavirus disease 2019 vaccine, there have been many reports of its adverse effects. While respiratory symptoms are common, many other symptoms in various organs have been reported. Herein, we report a case of optic disc and retinal hemorrhage that developed immediately after coronavirus disease 2019 vaccination.

CASE PRESENTATION

A healthy 18-year-old Japanese female noticed floater in the left eye 1 day after the second vaccination for coronavirus disease 2019 (Pfizer Inc.). Her visual acuity was 20/20 in the left eye, and Goldmann visual field test showed a relative scotoma around blind spot and in the temporal lower quadrant. It was considered due to subretinal hemorrhage and optic disc swelling. Fundus examination revealed retinal and optic disc hemorrhage. Pupillary reflex was intact and central critical flicker was not impaired, indicating that optic nerve was not involved. There was no sign of inflammation, vascular abnormality, nor history of an intense Valsalva maneuver. The hemorrhage resolved spontaneously within 5 months.

CONCLUSION

This case expands the clinical presentation of coronavirus disease 2019 vaccination-associated ocular adverse events, and it should be kept in mind when patients with similar symptoms visit clinics. The case report will help clinicians avoid unnecessary and invasive examinations and treatment.

Impact of COVID-19 Vaccination on Heart Rate Variability: A Systematic Review

Establishing and disseminating evidence-based safety information could potentially facilitate beneficial choices in coronavirus disease (COVID-19) vaccinations. This systematic review investigated the potential impact of COVID-19 vaccinations on human heart rate variability (HRV) parameters through comprehensive searches of four electronic medical databases. Five observational studies reporting HRV parameters of individuals vaccinated against COVID-19 and published up to 29 July 2022 were included in this review. Among them, four studies reported the square root of the mean squared differences of successive NN intervals (RMSSD) as their outcome, and the remaining study reported an HRV-based stress indicator. These studies reported short-term changes and rapid recovery in HRV parameters within up to 3 days after COVID-19 vaccination. Some studies showed that the impact of COVID-19 vaccinations on RMSSD was greater in women than men, and in the younger group than in the older group. The methodological quality of the included studies was not optimal; the review revealed short-term changes in HRV parameters, particularly RMSSD, following COVID-19 vaccination. However, as the included studies did not report important parameters besides RMSSD, the limitation exists that the postvaccination long-term HRV stability was not reported.

Pfizer-BioNTech (BNT162b2), Moderna (mRNA-1273) COVID-19 mRNA vaccines and hypersensitivity reactions

The SARS-CoV-2 Virus (COVID-19) is responsible for over 239 million cases and 4.8 million deaths globally (Data source WHO COVID-19 Dashboard accessed on October 14, 2021). It continues to surge and ravage countries, leaving healthcare systems in constant struggle and uncertainty. A variety of vaccines were developed to combat the spread of the COVID-19 Virus. Reports of possible allergic reactions with COVID-19 vaccines are a significant cause of public concern, especially among those with a known history of a severe allergic reaction (e.g., anaphylaxis). Here we review articles relevant to COVID-19 vaccines and their excipients (especially PEG (Polyethylene glycol) and hypersensitivity reactions associated with COVID-19 vaccines (including clinical features, pathophysiology, special populations receiving COVID-19 vaccinations, potential diagnostic tests, and preventive measures that can be taken to minimize the risks of hypersensitivity reactions with COVID-19 vaccines).

Evaluation and comparison of post-vaccination adverse effects among Janssen and Oxford-AstraZeneca vaccinated adult individuals in Debre Tabor Town: A cross- sectional survey in Northwest Ethiopia

COVID 19 vaccination has recently been launched globally to halt the pandemic. But COVID 19 vaccines have some adverse effects that raise concerns in the global community. This study aimed to evaluate and compare the adverse effects of Janssen and Oxford-AstraZeneca vaccinated adults. A community-based cross-sectional study was conducted from March 15 to 30, 2022 among 421 (211 Janssen and 210 Astra Zeneca vaccinated) adults recruited by a convenience sampling technique in Debre Tabor Town, Northwest Ethiopia. Data were collected via face-to-face interviews and by reviewing the immunization card. Chi-square test, independent t-test, and Mann-Whitney test were used to compare the adverse symptoms and related parameters between the two vaccines. A linear regression model was also used to identify predictors of the number of post-vaccination symptoms. The majority (75.8%) of participants reported at least one side effect after vaccination. Adverse symptoms had a significantly greater occurrence (p < .05) among recipients of the AstraZeneca vaccine (84.8%) than receivers of the Janssen vaccine (66.8%). The main adverse symptoms were injection site pain, fever, fatigue, arthralgia, and myalgia in both vaccines. Significant variations (p < .05) between the receipts of the two vaccines were shown in injection site pain, fever, and arthralgia. The total number of symptoms was significantly higher (p < .05) in participants with female sex, younger age, BMI <25 kg/m2, no prior COVID 19, and those who had received AstraZeneca vaccine. Thus, the authors advise that they should receive vaccines with no hesitation, while continuous tracking of vaccine safety is kept in place.

Basophil Activation Test with Different Polyethylene Glycols in Patients with Suspected PEG Hypersensitivity Reactions

Allergic reactions to COVID-19 vaccine components are rare but should be considered. Polyethylene glycol (PEG) is responsible for anaphylaxis in mRNA vaccines. Skin tests have been used in the allergological work-up programs for COVID-19 vaccine evaluation. However, the reproducibility of the skin prick test is time-dependent and the reactivity declines over time. Therefore, we combined the administration of the skin tests with the basophil activation test (BAT) using PEG2000, PEG4000 and DMG-PEG2000, where the BAT was considered positive when the percentage of activated basophils was higher than 6%, 5% and 6.5%, for PEG 4000, PEG2000 and DMG-PEG2000, respectively. To this end, among the subjects that underwent allergy counseling at the Allergy Unit of our Institution during the 2020/2021 vaccination campaign, 13 patients had a suggested medical history of PEG/drug hypersensitivity and were enrolled together with 10 healthy donors. Among the enrolled patients 2 out of 13 tested patients were positive to the skin test. The BAT was negative in terms of the percentages of activated basophils in all analyzed samples, but the stimulation index (SI) was higher than 2.5 in 4 out of 13 patients. These data evidenced that, when the SI is higher than 2.5, even in the absence of positivity to BAT, the BAT to PEG may be a useful tool to be coupled to skin tests to evidence even low-grade reactions.

Adverse events reported after first dose of SARS-CoV-2 vaccine in the Northern Region of Ghana

AIM

The study examined the associated adverse events following SARS-CoV-2 vaccination among healthcare workers during the first dose of the vaccine in the Northern Region of Ghana.

DESIGN

The study was a cross-sectional survey involving 463 healthcare workers.

METHOD

The data were collected using a structured questionnaire. The data were analysed descriptively, and binary logistics was performed using SPSS version 25.

RESULTS

The mean age was 33.4 ± 9.7 years, the majority (43.6%) being ≤30 years and males (57.2%). The self-reported prevalence of SARS-CoV-2 vaccine adverse events was 75.5%. Common systemic adverse events comprised headache (47.5%), dizziness (18.4%) and local adverse events included generalized body pains (44.0%) and abscess around the injection sites (11.2%). The study found a high prevalence of self-reported SARS-CoV-2 vaccine adverse events involving both systemic and local adverse events. Our study gives useful information that can be used for public health-targeted interventions to boost public confidence in SARS-CoV-2 vaccines.

PEG allergy - A COVID-19 pandemic-made problem? A German perspective

Background

Polyethylene glycol (PEG) has been used for decades, but only caused allergic reactions exceptionally. Introduction of PEG-containing COVID-19 vaccines might have fostered public interest beyond medical reasoning.

Objectives

To investigate the impact of the SARS-CoV-2 pandemic on the public interest in PEG allergy in Germany and the published PEG allergy cases worldwide.

Methods

A retrospective longitudinal study was conducted to measure public interest in PEG allergy analyzing Google search volume in Germany from February 2018 to January 2022. Medically confirmed “PEG allergy” cases were analyzed by looking at the numbers of PubMed case reports and case series from 1977 until January 2022.

Results

Web results in Germany before COVID-19 show search volumes related to “PEG allergy/testing” was negligible, with 10 search queries per month. The pandemic led to a >200-fold increase from 250 queries 2 years before to 55 720 queries 2 years thereafter, reflecting tremendous public interest. Additionally, the maximum monthly search volume from before to during the pandemic increased immensely for “vaccination” (57-fold), “vaccination and adverse effects” (85-fold), “vaccination and allergy” (71-fold). In contrast, the increase of publication numbers for the search term “PEG allergy” was small from 2019 to 2021 (2.5-fold). Only a very low number of 211 cases with “PEG allergy” worldwide since 1977 could be identified.

Conclusion

PEG allergy became a topic of major public interest because of COVID-19 vaccination. Scientific publications have increased to a lesser extent, probably promoted by public awareness. Conversely, the overall number of cases published with PEG allergy remain very low. The current high demand for COVID-19 vaccination allergy testing is triggered by public interest instead of medical reasoning.

Protective role of zinc in the pathogenesis of respiratory diseases

Respiratory diseases remain a major cause of morbidity and mortality worldwide. An imbalance of zinc, an essential trace element, is associated with a variety of lung diseases. We reviewed and summarized recent research (human subjects, animal studies, in vitro studies) on zinc in respiratory diseases to explore the protective mechanism of zinc from the perspective of regulation of oxidative stress, inflammation, lipid metabolism, and apoptosis. In the lungs, zinc has anti-inflammatory, antioxidant, and antiviral effects; can inhibit cancer cell migration; can regulate lipid metabolism and immune cells; and exerts other protective effects. Our comprehensive evaluation highlights the clinical and experimental effects of zinc in the pathogenesis of respiratory diseases. Our analysis also provides insight into the clinical application of zinc-targeted therapy for respiratory diseases.

Anaphylaxis to SARS-CoV-2 Vaccines in the Setting of a Nationwide Passive Epidemiological Surveillance Program

BACKGROUND

Information on anaphylaxis among recipients of vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains scarce.

OBJECTIVE

To identify the observed incidence of anaphylaxis in recipients of different anti-SARS-CoV-2 vaccines.

METHODS

A nationwide observational study among recipients of 61,414,803 doses of seven different anti-SARS-CoV-2 vaccines, describing the incidence and characteristics of adult patients (age ≥ 18 years) who developed anaphylaxis as an adverse event following immunization (AEFI) against SARS-CoV-2 vaccines between December 24, 2020, and October 15, 2021, in Mexico.

RESULTS

Sixty-six patients developed anaphylaxis as an AEFI, for an overall observed incidence of 1.07 cases per 1,000,000 (95% CI 0.84-1.37) administered doses. Eighty-six percent of the patients were female, consistent with previous reports of AEFI to COVID-19 vaccines. mRNA-based vaccine recipients had the highest frequency of anaphylaxis, followed by adenovirus-vectored vaccines and inactivated virus recipients, with an observed incidence of 2.5, 0.7, and 0.2 cases per 1,000,000 doses administered, respectively. Only 46% of the patients received correct treatment with epinephrine as the first-line treatment through the appropriate route and dose. We detected one case of anaphylactic reaction-related death occurring 5 min following immunization with ChAdOx1 nCov-19 for a mortality rate of 1.5% among those who developed this AEFI.

CONCLUSIONS

In our population, anaphylactic reactions were infrequent. Our study provides further evidence supporting the security of these newly developed vaccines.

What have we learned about the allergenicity and adverse reactions associated with the severe acute respiratory syndrome coronavirus 2 vaccines: One year later

OBJECTIVE

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the most rapid response and scale-up in vaccine and therapeutic development in history. We highlight the history of these amazing achievements with a focus on the description of the classification and mechanisms of allergic reactions and adverse events relevant to the allergist and immunologist that have been associated with the SARS-CoV-2 vaccines. Finally, we offer a detailed management approach in the context of a possible allergic reaction.

DATA SOURCES

Using defined search strategy, we identified peer-reviewed articles within PubMed that were published between January 1, 2019, and December 4, 2021.

STUDY SELECTIONS

All recent articles on COVID-19 published in English were reviewed with focus on the immunogenicity and allergenicity of the current existing COVID-19 vaccines.

RESULTS

Following a detailed literature review, we discuss the evolution and development of the new vaccines for SARS-CoV-2. Furthermore, we provide evidence regarding the significance and mechanisms of allergic reactions associated with the vaccines and offer a management approach for those with an increased risk of presenting an allergic or other relevant vaccine reaction.

CONCLUSION

The international rollout of COVID-19 vaccination started with reports of immediate allergic reactions. Although we still need to understand the mechanisms of these reactions, we can be reassured that patients with underlying allergic disease will not need to avoid SARS-CoV-2 vaccination. In addition, the vast majority of those with a first-dose reaction will tolerate subsequent doses.

Anaphylaxis to additives in vaccines

Anaphylaxis in connection with the administration of vaccines occurs only very rarely. Triggers of immunoglobulin IgE-mediated and non-IgE-mediated anaphylaxis—in addition to the active ingredient itself—may be excipients contained in the vaccine due to their special properties. Some of the excipients in medicinal products are the same compounds used as additives in food. Furthermore, residues from the manufacturing process (e.g., chicken egg white, casein, antibiotics, formaldehyde) or contaminants (e.g., from the primary packaging material) may be potential triggers of anaphylaxis in vaccines. This review article provides an overview of ingredients in vaccines that pose an allergenic risk potential. The components of COVID-19 vaccines approved and marketed in Germany are discussed with regard to their potential for triggering anaphylaxis and possible pathophysiological mechanisms involved.

Anaphylaxie auf Zusatzstoffe in Impfstoffen

Anaphylaxien im zeitlichen Zusammenhang mit der Verabreichung von Impfstoffen treten nur sehr selten auf. Auslöser von IgE-vermittelten und nicht IgE-vermittelten Anaphylaxien können neben dem Wirkstoff selbst Hilfsstoffe sein, die aufgrund spezieller Eigenschaften im Impfstoff enthalten sind. Bei den Hilfsstoffen in Arzneimitteln handelt es sich teilweise um dieselben Verbindungen, die als Zusatzstoffe in Lebensmitteln eingesetzt werden. Weiterhin kommen in Impfstoffen Rückstände aus dem Herstellungsprozess (z. B. Hühnereiweiß, Kasein, Antibiotika, Formaldehyd) oder Kontaminationen (z. B. aus dem Primärpackmittel) als potenzielle Auslöser von Anaphylaxien in Frage. Der vorliegende Review gibt einen Überblick über Bestandteile in Impfstoffen, von denen ein allergenes Risikopotenzial ausgeht. Die Bestandteile der in Deutschland zugelassenen COVID-19-Impfstoffe als potenzielle Auslöser von Anaphylaxien und mögliche pathophysiologische Mechanismen werden diskutiert.

Zitierweise: Mahler V, Junker AC. Anaphylaxis to additives in vaccines. Allergo J Int 2022;31: 123-36

https://doi.org/10.1007/s40629-022-00215-8