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

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.

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.

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.

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.

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.

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

The value of the basophil activation test in the evaluation of patients reporting allergic reactions to the BNT162b2 mRNA COVID-19 vaccine

BACKGROUND

mRNA-based COVID-19 vaccines have been reported to induce hypersensitivity reactions (HSR) in a small number of individuals. We aimed to evaluate the real-world incidence of the BNT162b2 mRNA COVID-19 vaccine HSR and to determine the value of the basophil activation test (BAT) in the allergological workup of patients reporting these reactions.

METHODS

We prospectively enrolled patients with a clinical history indicative of HSR to the BNT162b2 mRNA COVID-19 vaccine. The allergological workup included skin testing (STs) and BAT with polyethylene glycol (PEG) and the vaccine. In those with negative allergy assessments, the administration of the second dose of the BNT162b2 mRNA COVID-19 vaccine was offered.

RESULTS

Seventeen adults were included. Eleven cases (64.7%) tested negative in the allergological workup and tolerated the re-administration of the second dose of the vaccine and considered non-allergic. Six cases (35.3%) were considered allergic and classified into three groups: 2 subjects displayed positive STs and/or BAT to PEG (Group A), two individuals displayed positive BAT to the vaccine (Group B), and in 2 patients with moderate or severe reactions, the culprit was not identified, tested negative to STs and BAT to both PEG and vaccine (Group C). We further evaluated the value of BAT when the results were positive to the vaccine and negative to PEG by performing BAT in controls groups, finding positive BAT results in 50% of controls, all of them recovered from COVID-19 infection. In contrast, BAT was negative in patients who had not suffered from COVID-19 disease.

CONCLUSIONS

BAT can be used as a potential diagnostic tool for confirming allergy to PEG excipient but not to the vaccine as a positive result in BAT may indicate a past COVID-19 infection instead of an allergy.

Current Evidence in SARS-CoV-2 mRNA Vaccines and Post-Vaccination Adverse Reports: Knowns and Unknowns

The novel mRNA vaccinations against COVID-19 are gaining worldwide attention for their potential efficacy, as well as for the diagnosis of some post-vaccination-reported adverse reactions. In this state-of-the-art review article, we present the current evidence regarding mainly the diagnosis of spontaneous allergic reactions, the skin occurrences, the vascular, blood, endocrine and heart events, the respiratory reports, the gastrointestinal, hepatic and kidney events, the reproductive and pregnancy issues and the muscle events, as well as the ear, eye, neurologic and psychiatric events following mRNA vaccination against COVID-19. We further present some evidence regarding the mRNA strategies, we provide important information for side effects associated with the spike protein based LNP-mRNA vaccine and its adjuvants, as well as evidence for all the possible dangerous roles of the spike protein, and we discuss our expert opinion on the knowns and the unknowns towards the topic.

Adverse Reactions to Anti-Infective Vaccines: an Emerging Problem in the COVID-19 Era

Purpose of review

Vaccines are an essential tool for preventing infectious diseases and reducing associated morbidity and mortality. Vaccination has a significant impact at both individual and community levels, and COVID‐19 vaccination programs are a new example of the great value of this public health strategy. However, adverse reactions, especially severe reactions such as anaphylaxis, prevent these programs from progressing properly, thus limiting vaccination uptake in the population.

Recent findings

The frequency of reactions and types of vaccine components, with special attention to COVID-19 vaccines studies, provides information on the magnitude and causes of adverse events. The understanding of mechanisms involved has made it possible to adequately guide diagnosis, especially to COVID-19 vaccine components, such as polyethylene glycol, trometamol, and polysorbate-80.

Summary

This review focuses on adverse reactions to vaccines, with emphasis on allergic reactions. A diagnostic pathway is suggested that, on the one hand, enables to take the necessary precautions in persons with a history of allergy to vaccine components or allergic reactions to vaccines and, on the other, supports administration of subsequent doses. The overall objective is to ensure that people with allergy can be vaccinated in the same way as the rest of the population, and that they are offered alternatives where necessary.

Elevated Histamine Etiology Model for Most Major Vaccine Associated Adverse Events including SARS-CoV-2 Spike Vaccines

Vaccinees experience no adverse events, mild adverse events, multiple adverse events, or serious adverse events post vaccination. Many of these vaccine adverse events occur with different vaccines with different occurrence frequencies. Many of these adverse events are generally considered as associated with immune responses to the active vaccine components (antigens) and/or to possibly one or more of the vaccine excipients. Most of these vaccine adverse events are self-limiting and resolve within days. Many of these adverse events symptoms overlap symptoms associated with elevated histamine levels. Based on these observations, the hypothesis that the majority of vaccine associated reactogenicity adverse events are caused by temporal histamine intolerance in vaccinees is proposed. This hypothesis is based on a model of innate immune responses releasing a surge of inflammatory molecules including histamine; this surge is hypothesized to exceed the normal histamine tolerance level for vaccinees with reactogenicity adverse events. Further, these symptoms resolve as histamine levels fall below the vaccinee's tolerance threshold. This model can be evaluated by the detection of elevated histamine levels in vaccinees corresponding to timing of symptoms onset. If confirmed, a direct consequence of this model predicts that some antihistamine treatments, mast cell stabilizers, and possibly diamine oxidase enzyme may reduce the incidence or severity of adverse events experienced by vaccinees post vaccinations for most or all high reactogenicity vaccines including coronavirus disease 2019 (COVID-19) Spike vaccines.

Immediate Hypersensitivity Reactions Induced by COVID-19 Vaccines: Current Trends, Potential Mechanisms and Prevention Strategies

As the world deals with the COVID-19 pandemic, vaccination remains vital to successfully end this crisis. However, COVID-19-vaccine-induced immediate hypersensitivity reactions presenting with potentially life-threatening systemic anaphylactic reactions are one of the reasons for vaccine hesitancy. Recent studies have suggested that different mechanisms, including IgE-mediated and non-IgE-mediated mast cell activation, may be involved in immediate hypersensitivity. The main culprits triggering hypersensitivity reactions have been suggested to be the excipients of vaccines, including polyethylene glycol and polysorbate 80. Patients with a history of allergic reactions to drugs, foods, or other vaccines may have an increased risk of hypersensitivity reactions to COVID-19 vaccines. Various strategies have been suggested to prevent hypersensitivity reactions, including performing skin tests or in vitro tests before vaccination, administering different vaccines for the primary and following boosters, changing the fractionated doses, or pretreating the anti-IgE antibody. This review discusses the current trends, potential mechanisms, and prevention strategies for COVID-19-vaccine-induced immediate hypersensitivity reactions.

Atypical Kawasaki Disease after COVID-19 Vaccination: A New Form of Adverse Event Following Immunization

Kawasaki disease (KD) is a medium-vessel vasculitis that is typically presented during childhood; fewer than 100 cases of KD have been reported worldwide in adult patients who met the criteria according to the American College of Rheumatology. This study presents the case of an 18-year-old patient with no previous history of any disease, who presented atypical KD with liver and kidney dysfunction, with a good response to intravenous immunoglobulin therapy. The symptoms began 22 days after the application of the COVID-19 vaccine (nonreplicating viral vector Vaxzevria), and other conditions were ruled out. The term Adverse Events Following Immunization (AEFI)encompasses all the reactions that follow the application of any vaccine with no necessary causal relationship and can be due to the vaccine product, quality of the vaccine, immunization errors, or anxiety or just happen to be coincident events. These reactions should be reported so that clinicians can identify compatible cases and consider that the presentation of this disease, despite being atypical, can be manifested in adult patients. Likewise, case reports are an important basis for the pharmacovigilance of vaccines.

Delayed urticaria after BNT162b2 booster vaccination at previous intradermal test site with severe acute respiratory syndrome-coronavirus-2 spike protein

Urticaria is a common cutaneous adverse event from coronavirus disease 2019 vaccination. Previous studies hypothesized that excipients as polyethylene glycol in BNT162b2 vaccine and polysorbate in ChAdOx1 nCoV-19 vaccine are allergens. A 28-year-old woman had urticaria after a booster vaccination with BNT162b2 at the site of previous intradermal injection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) spike protein. This reaction emphasized that delayed urticaria may not be an allergic reaction to excipient but rather to the immunogen as such as SARS-CoV-2 spike protein.

Chronic spontaneous urticaria after BNT162b2 mRNA (Pfizer-BioNTech) vaccination against SARS-CoV-2

Background: The factors that trigger and exacerbate chronic spontaneous urticaria (CSU) are well known, but it is not unclear whether messenger RNA (mRNA) vaccination against severe acute respiratory syndrome coronavirus 2 can trigger new cases of CSU or a relapse of CSU after long-term remission. Objective: To study the clinical cases of patients with new-onset CSU and CSU in remission who relapsed within 3 months after BNT162b2 mRNA vaccination. Methods: All patients with a CSU diagnosis within 12 weeks of BNT162b2 mRNA vaccination were retrospectively identified and included in the new-onset CSU and the relapsed CSU groups. The first control group (CSU control group) retrospectively consisted of patients diagnosed with CSU in complete clinical remission for ≥ 6 months, with no CSU relapse after vaccination. The second control group (healthy control group) consisted of subjects who were fully vaccinated and without CSU, matched 1:2 for age and sex with patients with CSU. Results: Twenty-seven patients were included in the relapsed CSU group, 32 patients in the new-onset CSU group, 179 patients in the CSU control group, and 476 subjects in the healthy control group. The relapsed CSU and new-onset CSU groups had more allergic comorbidities overall (19 [70.4%] and 13 [40.6%], respectively) than the CSU control group and the healthy control group (50 [27.9%] and 110 [23.1%], respectively; p < 0.001). Multiple logistic regression analysis showed that a positive autologous serum skin test result, overall allergic comorbidities, and basopenia were positively associated with the probability of CSU relapse within 3 months after BNT162b2 mRNA vaccination (odds ratio [OR] 5.54 [95% confidence interval {CI}, 2.36-13.02], p < 0.001); OR 6.13 [95% CI, 2.52-14.89], p = 0.001; and OR 2.81 [95% CI, 1.17-6.72, p = 0.020, respectively). Conclusion: It is possible that BNT162b2 mRNA vaccination serves as a provoking and/or relapsing factor of CSU in individuals with allergic diseases and/or predisposed autoimmunity.