Vaccination and anaphylaxis: a forensic perspective

Anaphylaxis and allergic reactions to COVID-19 vaccines: A narrative review of characteristics and potential obstacles on achieving herd immunity

Background and Aims

Coronavirus disease 2019 (COVID-19) is a highly contagious infection, and new variants of its causative virus continue to emerge all around the world. Meanwhile, mass vaccination represents a highly effective measure to reduce the disease burden. Not only do vaccines immunize individuals, but they also protect the entire population through achieving herd immunity. They are composed of various ingredients, some of which may induce hypersensitivity reactions, namely anaphylaxis and cutaneous allergic reactions. This review aims to provide an explicit overview of the pathophysiology, suspected responsible components, and management of COVID-19 vaccine-induced allergic reactions, and their effect on acquiring herd immunity.

Methods

To perform this narrative review, a comprehensive literature search based on our selected terms was conducted in online databases of PubMed/Medline and Google Scholar for finding the relevant studies published from 2019 to 2022.

Results

COVID-19 vaccines introduce several advantages that outweigh their potential risks, such as allergic reactions. Allergic reactions are mainly attributed to polyethylene glycol and polysorbate excipients that can provoke IgE-mediated reactions and hypersensitivity reactions. These reactions should be managed properly to avoid having serious sequelae.

Conclusion

It is of great importance to immediately recognize and manage vaccine hypersensitivity reactions, especially anaphylaxis, to avoid allergic patients being excluded from the vaccination program, and more importantly, to stop the spreading of unfounded vaccine hesitancy leading to delayed herd immunity.

Postmortem investigation of fatalities following vaccination with COVID-19 vaccines

Thorough postmortem investigations of fatalities following vaccination with coronavirus disease 2019 (COVID-19) vaccines are of great social significance. From 11.03.2021 to 09.06.2021, postmortem investigations of 18 deceased persons who recently received a vaccination against COVID-19 were performed. Vaxzevria was vaccinated in nine, Comirnaty in five, Spikevax in three, and Janssen in one person. In all cases, full autopsies, histopathological examinations, and virological analyses for the severe acute respiratory syndrome coronavirus 2 were carried out. Depending on the case, additional laboratory tests (anaphylaxis diagnostics, VITT [vaccine-induced immune thrombotic thrombocytopenia] diagnostics, glucose metabolism diagnostics) and neuropathological examinations were conducted. In 13 deceased, the cause of death was attributed to preexisting diseases while postmortem investigations did not indicate a causal relationship to the vaccination. In one case after vaccination with Comirnaty, myocarditis was found to be the cause of death. A causal relationship to vaccination was considered possible, but could not be proven beyond doubt. VITT was found in three deceased persons following vaccination with Vaxzevria and one deceased following vaccination with Janssen. Of those four cases with VITT, only one was diagnosed before death. The synopsis of the anamnestic data, the autopsy results, laboratory diagnostic examinations, and histopathological and neuropathological examinations revealed that VITT was the very likely cause of death in only two of the four cases. In the other two cases, no neuropathological correlate of VITT explaining death was found, while possible causes of death emerged that were not necessarily attributable to VITT. The results of our study demonstrate the necessity of postmortem investigations on all fatalities following vaccination with COVID-19 vaccines. In order to identify a possible causal relationship between vaccination and death, in most cases an autopsy and histopathological examinations have to be combined with additional investigations, such as laboratory tests and neuropathological examinations.

Significance of detecting postmortem serum IgE in frozen corpses for the diagnosis of anaphylaxis in forensic

The aim of this study was to detect the postmortem serum total IgE levels in frozen corpses and identify whether the death incident caused by an anaphylaxis in forensic medicine. Autopsy cases with pathological death (total, n = 106; 4-214 h postmortem) include cardiac disease (n = 15), pulmonary infection (n = 12), central nervous system disorder (n = 6), pulmonary emboliszn (n = 7), hapetic disease (n = 5), kidney disease (n = 6), enteric disease (n = 10), necrotizing pancreatitis (n = 7), diffuse peritonitis (n = 6), MODS (n = 6), toxicosis (n = 5:), anaphylactic shock (n = 7), bronchial asthma (n = 8) and other disease (n = 6) were examined. Results showed that there was no significant difference between serum IgE levels and ages, postmortem intervals (PMIs), gender as well as survival time. Serum IgE levels of deaths due to anaphylactic shock and bronchial asthma were higher than that of other groups. Forensic pathology examination results showed the main pathology changes of bronchial asthma were mucous congestion in bronchial lumen and eosinophils infiltration in bronchial mucosa. The main pathological features of anaphylactic shock were laryngeal edema and eosinophils infiltration in multiple organs (lung and spleen). This research proved that there was a great significance for IgE to infer whether the individual died due to an anaphylaxis even for a long PMI in frozen corpses. Furthermore, we can also preliminarily determine the type of allergic death combined with the examination of forensic pathology. These findings further verify the feasibility of postmortem serum IgE in the diagnosis of forensic causes of death and broaden the application scope of this marker.

A systematic assessment of the relationship between synthetic surfactants and mucosal adjuvanticity

Intranasal immunization with surfactants as vaccine adjuvants enhances protective immunity against invasive mucosal pathogens. However, the effects of surfactants and their adjuvanticity on mucosal immune responses remain unclear. Comparison of the mucosal adjuvanticity of 20 water-soluble surfactants from the four classes based upon the polarity composition of the hydrophilic headgroup revealed that the order of mucosal adjuvanticity was as follows: amphoteric > nonionic > cationic > anionic. Within the same class, each surfactant displayed different adjuvanticity values. Analysis of the diameter and ζ-potential of amphoteric surfactant-OVA complexes and their surface physicochemical properties revealed that the diameter was approximately 100 nm, which is considered suitable for immune induction, and that the ζ-potential of the anionic surfactant-OVA complexes was exceedingly negative. The increase in the number of carbon atoms in the hydrophobic tailgroups of the amphoteric surfactant resulted in an increase in the OVA-specific Ab titers. Our findings demonstrate that amphoteric surfactants exhibit potent mucosal adjuvanticity and highlight the importance of the number of carbon atoms in the tailgroups and the diameter and ζ-potential of the complexes when designing mucosal adjuvants.

Allergic Reactions to Current Available COVID-19 Vaccinations: Pathophysiology, Causality, and Therapeutic Considerations

Vaccines constitute the most effective medications in public health as they control and prevent the spread of infectious diseases and reduce mortality. Similar to other medications, allergic reactions can occur during vaccination. While most reactions are neither frequent nor serious, anaphylactic reactions are potentially life-threatening allergic reactions that are encountered rarely, but can cause serious complications. The allergic responses caused by vaccines can stem from activation of mast cells via Fcε receptor-1 type I reaction, mediated by the interaction between immunoglobulin E (IgE) antibodies against a particular vaccine, and occur within minutes or up to four hours. The type IV allergic reactions initiate 48 h after vaccination and demonstrate their peak between 72 and 96 h. Non-IgE-mediated mast cell degranulation via activation of the complement system and via activation of the Mas-related G protein-coupled receptor X2 can also induce allergic reactions. Reactions are more often caused by inert substances, called excipients, which are added to vaccines to improve stability and absorption, increase solubility, influence palatability, or create a distinctive appearance, and not by the active vaccine itself. Polyethylene glycol, also known as macrogol, in the currently available Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines, and polysorbate 80, also known as Tween 80, in AstraZeneca and Johnson & Johnson COVID-19 vaccines, are excipients mostly incriminated for allergic reactions. This review will summarize the current state of knowledge of immediate and delayed allergic reactions in the currently available vaccines against COVID-19, together with the general and specific therapeutic considerations. These considerations include: The incidence of allergic reactions and deaths under investigation with the available vaccines, application of vaccination in patients with mast cell disease, patients who developed an allergy during the first dose, vasovagal symptoms masquerading as allergic reactions, the COVID-19 vaccination in pregnancy, deaths associated with COVID-19 vaccination, and questions arising in managing of this current ordeal. Careful vaccine-safety surveillance over time, in conjunction with the elucidation of mechanisms of adverse events across different COVID-19 vaccine platforms, will contribute to the development of a safe vaccine strategy. Allergists’ expertise in proper diagnosis and treatment of allergic reactions is vital for the screening of high-risk individuals.

The forensic spleen: Morphological, radiological, and toxicological investigations

The spleen is only uncommonly investigated in the forensic setting. Thorough examinations are performed in some specific situations such as splenic trauma (including iatrogenic trauma from cardiopulmonary resuscitation attempts), anaphylaxis, drowning, and sepsis-related deaths. The aim of this review is to present the available literature focusing on a few selected splenic diseases as well as forensic investigations performed on the spleen in order to summarize the most frequent situations in which this routinely unexplored organ may merit more extensive examination.

The forensic spleen: Morphological, radiological, and toxicological investigations

The spleen is infrequently investigated in forensic pathology routine. Thorough examinations are performed in very specific situations such as splenic trauma (including iatrogenic trauma from cardiopulmonary resuscitation attempts), anaphylaxis-related deaths, drowning and sepsis. The purpose of this review article is to provide a general overview of available literature focusing on a few selected splenic diseases as well as available forensic investigation techniques performed on the spleen in order to summarize the most frequent situations of forensic interest in which this routinely unexplored organ may merit more extensive examination.