Assessment of causality of individual adverse events following immunization (AEFI): a WHO tool for global use

Safety of medicinal and edible herbs from fruit sources for human consumption: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal and edible herbs from fruit sources have been increasingly used in traditional Chinese medicine dietotherapy. There are no restrictions on who could consume the medicinal and edible fruits or on the dosage of consumption. However, their safety for human consumption has yet to be established.

AIM OF THE STUDY

This systematic review aimed to assess the safety of human consumption of 30 medicinal and edible fruits.

MATERIALS AND METHODS

Seven English and Chinese databases were searched up to May 31, 2023, to collect AE reports following human consumption of medicinal and edible fruits. Eligible reports should include details on the occurrence, symptoms, treatments, and outcomes of AEs. AEs that were life-threatening or caused death, permanent or severe disability/functional loss, or congenital abnormality/birth defects were classified as serious AEs (SAEs). The causality between the consumption of fruits and AEs was graded as one of four ranks: "certain", "probable", "possible", or "unlikely".

RESULTS

Thirty AE reports related to the consumption of medicinal and edible fruits were included, involving 12 species of fruits: Crataegi fructus, Gardeniae fructus, Mori fructus, Hippophae fructus, Cannabis fructus, Siraitiae fructus, Perillae fructus, Rubi fructus, Longan arillus, Anisi stellati fructus, Zanthoxyli pericarpium, and Lycii fructus. No AE reports were found for the remaining 18 species. A total of 97 AEs, featuring predominantly gastrointestinal symptoms, followed by allergic reactions and neuropsychiatric symptoms, were recorded. Thirty SAEs were noted, with Zanthoxyli pericarpium accounting for the most (14 cases), followed by Perillae fructus (7 cases), Anisi stellati fructus (6 cases), and Gardeniae fructus, Rubi fructus, and Mori fructus (1 case each). Mori fructus was associated with one death. All AEs were concordant with a causality to fruit consumption, judged to be "certain" for 37 cases, "probable" for 53 cases, and "possible" for 7 cases.

CONCLUSIONS

Our findings suggest that among medicinal and edible fruits, 12 species have AE reports with a causality ranging from "possible" to "definite". SAEs were not scarce. Most AEs may be associated with an excessive dose, prolonged consumption, or usage among infants or young children. No AE reports were found for the remaining 18 species.

Revaccination outcomes among adolescents and adults with suspected hypersensitivity reactions following COVID-19 vaccination: A Canadian immunization research network study

BACKGROUND

COVID-19 vaccination has been associated with anaphylaxis and hypersensitivity reactions. Infectious disease physicians and allergists in the Canadian Special Immunization Clinic (SIC) Network developed guidance for evaluating patients with adverse events following immunization (AEFI) including suspected hypersensitivity. This study evaluated management and adverse event recurrence following subsequent COVID-19 vaccinations.

METHODS

Individuals aged 12 years and older enrolled at participating SICs before February 28, 2023 who were referred for suspected or diagnosed hypersensitivity reaction following COVID-19 vaccination, or for prevaccination assessment of suspected allergy to a COVID-19 vaccine component were included. De-identified clinical assessments and revaccination data, captured in a centralized database, were analyzed. The Brighton Collaboration case definition (BCCD) for anaphylaxis (2023 version) was applied.

RESULTS

The analysis included 206 participants from 13 sites: 26 participants referred for pre-vaccination assessment and 180 participants referred for adverse events following COVID-19 vaccination (15/180 [8.3%] with BCCD confirmed anaphylaxis, 84 [46.7%] with immediate hypersensitivity symptoms not meeting BCCD, 33 [18.3%] with other diagnosed hypersensitivity reactions, and 48 [26.7%] participants with a final diagnosis of non-hypersensitivity AEFI). Among participants referred for AEFIs following COVID-19 vaccination, 166/180 (92.2%) were recommended for COVID-19 revaccination after risk assessment, of whom 158/166 (95.2%) were revaccinated (all with a COVID-19 mRNA vaccine). After revaccination, 1/15 (6.7%) participants with prior anaphylaxis, 1/77 (1.3%) with immediate hypersensitivity not meeting criteria for anaphylaxis and 1/24 (4.2%) with other physician diagnosed hypersensitivity developed recurrent AEFI symptoms that met the BCCD for anaphylaxis. All 26 participants referred pre-vaccination, including 9 (34.6%) with history of polyethylene glycol-asparaginase reactions, were vaccinated without occurrence of immediate hypersensitivity symptoms.

CONCLUSIONS

Most individuals in this national cohort who experienced a hypersensitivity event following COVID-19 vaccination and were referred for specialist review were revaccinated without AEFI recurrence, suggesting that specialist evaluation can facilitate safe revaccination.

Medical occurrence and safety of SARS-CoV-2 vaccination outside of the hospital setting

During COVID-19 pandemic, vaccination has been strongly recommended and advocated to prevent COVID-19 infection and adverse outcomes, particularly among at-risk populations. The vaccination against SARS-CoV-2 (COVAC) occurred at off-site locations capable of accommodating large crowds, distinct from the hospital setting, where a team of intensivists, emergency physicians, and nurses, ensuring prompt medical attention (medical occurrences, MO) in cases of adverse event following immunization. Our aims were to estimate the incidence of MO, and to assess its association with demographics, and vaccine characteristics. Our retrospective cohort study included all subject aged 12 years and older who received vaccinations at two large out-of-hospital vaccination hubs (Fiera Milano City, Palazzo delle Scintille), between April 12th and August 31st, 2021. Nine hundred and ninety-five thousand and twenty-eight vaccinations were administrated. MOs incidence rate was 278/100,000 doses (95% confidence interval (CI) 268-289). Most MOs were mild (86.27%) and mainly observed in subjects who received the Comirnaty vaccine; 92 MOs (3.32%) were severe and mostly occurred in recipients of the Vaxzeria vaccine. The incidence rate for hospital transfers following vaccination was 4.7/100,000 doses (95% CI 3.5-6.2) and any level of anaphylaxis occurred in 0.4 cases per 100,000 administrated doses (95% CI 0.3.-0.7). Sex, age, type of vaccine and first dose were associated with incidence of MO. Our results showed a low incidence rate in MOs after COVAC, mainly mild and support the feasibility, effectiveness and safety of vaccinations administered in hubs with a dedicated SEU located outside of the hospital setting.

Safety profile assessment of HPV4 and HPV9 vaccines through the passive surveillance system of the Veneto Region (Italy) between 2008 and 2022: A 15-year retrospective observational study

In Veneto Region, HPV vaccine has been actively offered to 12 year-old females since 2008, and to 12 year-old males since 2015. The study aims to analyze the safety profile of HPV4v and HPV9v vaccines and perform a case-by-case review of conditions of interest. Spontaneous reports related to HPV uploaded to the database of the Regional Pharmacovigilance Center between 2008-2022 were included. HPV vaccine doses administered until April 2022 in the Veneto Region were considered to calculate the reporting rate (RR). Potential "safety concerns" examined as conditions of interest were included through Standardized MedDRA or preferred terms searching queries. The level of diagnostic certainty was evaluated as per the Brighton Collaboration case definition criteria. A total of 637 reports and 1316 Adverse Events Following Immunizations (AEFI) were retrieved: 469 for HPV4v (73.6 %) and 168 for HPV9v (26.4 %). Serious reports were 71 (11.1 %): 49 (10.4 %) for HPV4v and 22 (13.1 %) for HPV9v. The RR for serious events between 2008-2022 was 6.9/100,000 administered doses, with no differences by vaccine type. Females and adults showed higher overall RR compared to males and to children and adolescents (p < 0.001), this result was confirmed by stratifying analysis by vaccine type. One case of Guillain Barré syndrome, anaphylactic shock, thrombocytopenia, Henoch Schoenlein purpura and four generalized seizures were reviewed. Vaccinovigilance data from the Veneto Region reaffirm a good safety profile for HPV vaccination and found no vaccine-related unexpected events. Such a detailed analysis may assist healthcare providers to advocate properly for HPV vaccination.

Factors associated with intention for revaccination among patients with adverse events following immunization

OBJECTIVES

Individuals and healthcare providers may be uncertain about the safety of revaccination after an adverse event following immunization (AEFI). We identified factors associated with physician recommendation for revaccination and participant intention to be revaccinated among patients with adverse events following immunization (AEFIs) assessed in the Canadian Special Immunization Clinic (SIC) Network from 2013 to 2019.

METHODS

This prospective observational study included patients assessed in the Canadian Special Immunization Clinic Network from 2013 to 2019 for an AEFI who required additional doses of the vaccine temporally associated with their AEFI. Participants underwent standardized assessment and data collection. Physician recommendations regarding revaccination and participant intent for revaccination were recorded. AEFI impact on daily activities and need for medical attention was captured as low, moderate, high impact and serious (e.g., requiring hospitalization). Multivariable logistic regression analysis identified factors associated with physician recommendation and participant intention for revaccination, controlling for province of assessment.

RESULTS

Physician recommendation was significantly associated with the type of AEFI and AEFI impact. Compared to large local reaction, physician recommendation for revaccination was reduced for immediate hypersensitivity (aOR: 0.24 [95% CI: 0.08-0.76]) and new onset autoimmune disease (aOR: 0.16; 95% CI: 0.04-0.69). Compared to low impact AEFIs, physician recommendation was reduced for moderate (aOR: 0.22 [95% CI: 0.07-0.65]), high impact (aOR: 0.08 [95% CI: 0.02-0.30]), and serious AEFIs (aOR: 0.11 [95% CI: 0.03-0.37]). Participant intention for revaccination was significantly associated with AEFI impact, with reduced odds for high versus low impact AEFIs (aOR: 0.12 [95% CI: 0.04-0.42]).

CONCLUSION

Physicians appear to use AEFI type and impact to guide recommendations while patients use primarily AEFI impact to form intentions for revaccination. The findings may help inform counselling for patients with AEFIs.

COVID-19 Vaccine Adverse Event Detection Based on Multi-Label Classification With Various Label Selection Strategies

Analyzing massive VAERS reports without medical context may lead to incorrect conclusions about vaccine adverse events (VAE). Facilitating VAE detection promotes continual safety improvement for new vaccines. This study proposes a multi-label classification method with various term-and topic-based label selection strategies to improve the accuracy and efficiency of VAE detection. Topic modeling methods are first used to generate rule-based label dependencies from Medical Dictionary for Regulatory Activities terms in VAE reports with two hyper-parameters. Multiple label selection strategies, namely one-vs-rest (OvsR), problem transformation (PT), algorithm adaption (AA), and deep learning (DL) methods, are used in multi-label classification to examine the model performance, respectively. Experimental results indicated that the topic-based PT methods improve the accuracy by up to 33.69% using a COVID-19 VAE reporting data set, which improves the robustness and interpretability of our models. In addition, the topic-based OvsR methods achieve an optimal accuracy of up to 98.88%. The accuracy of the AA methods with topic-based labels increased by up to 87.36%. By contrast, the state-of-art LSTM- and BERT-based DL methods have relatively poor performance with accuracy rates of 71.89% and 64.63%, respectively. Our findings reveal that the proposed method effectively improves the model accuracy and strengthens VAE interpretability by using different label selection strategies and domain knowledge in multi-label classification for VAE detection.

Self-reported side effects following COVID-19 vaccination in athletes: A retrospective study

Billions of coronavirus disease 19 (COVID-19) vaccines have been administered worldwide. However, limited data on side effects have been reported in athletes. This study aimed to describe the incidence of side effects following COVID-19 vaccination in athletes and to identify the factors associated with the main side effects in this population. Information on COVID-19 vaccination, side effects, and overall symptom duration was retrospectively collected from recreational and competitive athletes. A total of 460 participants were included in this study. Fever and arm pain were more frequently reported after the first-dose vaccination, 9.6% vs 4.6%, p = .007 and 81.3% vs 24.9%, p ≤ .001. Myalgia was more common after the second-dose vaccination, 0.65% vs. 7.1% p ≤ .001. Males were more likely to present with arm pain after the first and second vaccinations. Those with SARS-CoV-2 infection before vaccination were less likely to present with arm pain after the first dose of vaccination (OR: 0.162, p ≤ .001) and more likely to present with fever after the second dose of vaccination (OR: 3.442, p = .046). First-dose vaccination with the BNT162b2 vaccine compared to other brands was characterized by lower odds of fever (OR: 0.394, p = .017). Our results indicated mild adverse effects and a short duration of symptoms in athletes following COVID-19 vaccination.

Causality assessment of adverse drug reaction: A narrative review to find the most exhaustive and easy-to-use tool in post-authorization settings

BACKGROUND

The core motive of pharmacovigilance is the detection and prevention of adverse drug reactions (ADRs), to improve the risk-benefit balance of the drug. However, the causality assessment of ADRs remains a major challenge among clinicians, and none of the available tools of causality assessment used for assessing ADRs have been universally accepted.

OBJECTIVE

To provide an up-to-date overview of the different causality assessment tools.

METHODS

We conducted electronic searches in MEDLINE, EMBASE, and the Cochrane database. The eligibility of each tool was screened by three reviewers. Each eligible tool was then scrutinized for its domains (the reported specific set of questions/areas used for calculating the likelihood of cause-and-effect relation of an ADR) to discover the most comprehensive tool. Finally, we subjectively assessed the tool's ease-of-use in a Canadian, Indian, Hungarian, and Brazilian clinical context.

RESULTS

Twenty-one eligible causality assessment tools were retrieved. Naranjo's tool and De Boer's tool appeared the most comprehensive among all the tools, covering 10 domains each. Regarding "ease-of-use" in a clinical setting, we judged that many tools were hard to implement in a clinical context because of their complexity and/or lengthiness. Naranjo's tool, Jones's tool, Danan and Benichou's tool, and Hsu and Stoll's tool appeared to be the easiest to implement into various clinical contexts.

CONCLUSION

Among the many tools identified, 1981 Naranjo's scale remains the most comprehensive and easy to use for performing causality assessment of ADRs. Upcoming analysis should compare the performance of each ADR tool in clinical settings.

A narrative review of vaccine pharmacovigilance during mass vaccination campaigns: Focus on myocarditis and pericarditis after COVID-19 mRNA vaccination

Vaccines have had a tremendous impact on reducing the burden of infectious diseases; however, they have the potential to cause adverse events following immunization (AEFIs). Prelicensure clinical trials are limited in their ability to detect rare AEFIs that may occur in less than one per thousand individuals. While postmarketing surveillance systems have shown COVID-19 mRNA vaccines to be safe, they led to the identification of rare cases of myocarditis and pericarditis after COVID-19 vaccination that were not initially detected in clinical trials. In this narrative review, we highlight concepts of vaccine pharmacovigilance during mass vaccination campaigns and compare the approaches used in the context of myocarditis and pericarditis following COVID-19 vaccination to historical examples. We describe mechanisms of passive and active surveillance, their strengths and limitations, and how they interacted to identify and characterize the safety signal of myocarditis and pericarditis after COVID-19 mRNA vaccination. Articles were synthesized from a PubMed search using relevant keywords for articles published on vaccine surveillance systems and myocarditis and pericarditis after COVID-19 vaccination, as well as the authors' collections of relevant publications and grey literature reports. The global experience around the identification and monitoring of myocarditis and pericarditis after COVID-19 mRNA vaccination has provided important lessons for vaccine safety surveillance and highlighted its importance in maintaining public trust in mass vaccination programmes in a pandemic context.

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.

Revaccination and Adverse Event Recurrence in Patients with Adverse Events following Immunization

OBJECTIVES

To estimate the risk of recurrence of adverse events following immunization (AEFIs) upon revaccination and to determine among patients with suspected vaccine allergy whether allergy skin test positivity was associated with AEFI recurrence.

STUDY DESIGN

This prospective observational study included patients assessed in the Canadian Special Immunization Clinic Network from 2013 to 2019 with AEFIs who required revaccination with the vaccine temporally associated with their AEFI. Participants underwent standardized assessment and data collection. Special Immunization Clinic physicians used guidelines to inform their recommendations. Participants were followed up after revaccination to capture AEFI recurrences. Data were transferred to a central database for descriptive analysis.

RESULTS

Overall, 588 participants were assessed for 627 AEFIs; 570 (91%) AEFIs occurred in children <18 years of age. AEFIs included immediate hypersensitivity (130/627; 21%), large local reactions (110/627; 18%), nonurticarial rash (51/627; 8%), seizures (26/627; 4%), and thrombocytopenia (11/627; 2%). Revaccination was recommended to 513 of 588 (87%) participants. Among participants recommended and due for revaccination during the study period, 63% (299/477) were revaccinated. AEFI recurrence was 10% (31/299) overall, 31% (15/49) for large local reactions, and 7% (5/66) for immediate hypersensitivity. No recurrence was serious. Among 92 participants with suspected vaccine allergy who underwent skin testing and were revaccinated, the negative predictive value of skin testing for AEFI recurrence was 96% (95% CI 92.5%-99.5%).

CONCLUSIONS

Most individuals with AEFIs were safely revaccinated. Among those with suspected vaccine allergy, skin testing may help determine the safety of revaccination.

COVID-19 mRNA Vaccines: A Retrospective Observational Pharmacovigilance Study

Background and Objective

Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus has caused millions of deaths worldwide. The mRNA vaccines prevented the figure from being more severe. The objective of this retrospective study is to evaluate the safety of COVID-19 vaccines by analyzing the adverse events following immunization (AEFIs).

Methods

A retrospective observational pharmacovigilance study was conducted, based on the collection of reports of suspected AEFIs reported between 1 January 2021 and 31 December 2021 at the Naples 3 local health authority. AEFIs were stratified and described according to mRNA vaccine, demographics, clinical status, description of AEFI, and degree of severity. In 2021, local health authority Asl Naples 3 South received 1164 reports of suspected adverse events that occurred following the administration of mRNA vaccines.

Results

During the reporting period, 746 reports were related to the Comirnaty vaccine (64.1%), 281 to the Vaxzevria vaccine (24.1%), 107 to the Spikevax vaccine (9.2%), and 30 to the Jcovden vaccine (2.6%); 89.3% of the reports were classified as not serious (N = 1039 reports), the remaining 10.7% as serious (N = 125 reports).

Conclusions

This retrospective pharmacovigilance study demonstrates that COVID-19 mRNA vaccines are safe in all population groups.

Pharmacovigilance is an activity that ensures the safety of health care treatments. The COVID-19 pandemic has accelerated the administration of vaccines whose efficacy and safety is to be evaluated. In the year 2021, an analysis of all reported adverse events following immunization (AEFIs) to the vaccine was conducted on a sample of about 1 million people with the aim of understanding efficacy and safety. All adverse events were divided by age, sex, type of reaction, and severity. Serious reactions were divided into subcategories to report the most common critical issues. At the conclusion of the work, it can be seen that COVID-19 mRNA vaccines are safe but can give serious cardiovascular (12% of the total number of serious reports) and neurological (one serious case that led to the development of Guillain Barré syndrome) side effects that need to be monitored by medical personnel.

Self-Reported Reactogenicity After Different COVID-19 Vaccination Regimens

BACKGROUND

In Rhineland-Palatinate, most COVID-19 vaccinations are centrally registered by the Rhineland-Palatinate Division of Vaccine Documentation, which includes self-reported vaccination reactions (SRVR) and their level of perceived intensity. We analyzed the occurrence of SRVR reported between 12/2020 and 12/2021 in relation to the different vaccination regimens involving BioNTech/Pfizer (BNT) and Moderna (m1273) mRNA vaccines and AstraZeneca (ChAd) and Johnson & Johnson (Ad26) viral vector vaccines.

METHODS

Using sex-specific logistic regression models, we analyzed the occurrence of all local and systemic SRVR, as well as the occurrence of local and systemic SRVR that were self-rated as "severe" by the vaccinated persons, in relation to the vaccine of the first vaccination and the vaccination regimen of the second vaccination (BNT/BNT, ChAd/ChAd, m1273/m1273, ChAd/ BNT, ChAd/m1273). Vaccination with BNT or the BNT/BNT regimen formed the reference category for the estimated odds ratios (OR) with respective 95% confidence intervals.

RESULTS

Of all those vaccinated, 40.7% provided valid information on SRVR after the first vaccination and 33.8% after the second vaccination. As a result, 887 052 individuals were included in the analyses. Their median age was 60 years, and 58% were women. The most common vaccination regimen was BNT/BNT (67.3%). The most common SRVR were pain at the injection site and fatigue. Self-reported reactogenicity after the first vaccination was lowest for BNT. Self-reported systemic reactogenicity was notably higher after vaccination with a vector vaccine. After the second vaccination, self-reported reactogenicity was lowest after a ChAd/ChAd regimen and highest after an m1273 second vaccination.

CONCLUSION

With overall acceptable tolerability, differences in self-reported reactogenicity were evident depending on the particular COVID-19 vaccines and vaccination regimens in question.

Henoch-Schönlein purpura following COVID-19 vaccine in a child: a case report

Background

Henoch-Schönlein purpura (HSP) is an IgA-mediated small vessel vasculitis, typical of childhood. It’s a self-limiting disease and it affects different systems. HSP is characterized by dermatological, abdominal, joint and renal clinical manifestations. This condition usually occurs upon infections, mainly upper respiratory tract ones, medications, vaccinations and malignancies.

Case presentation

We describe the case of a 11 year-old girl who developed a urticarial rash 12 days after the first dose of Pfizer-BioNTech BNT16B2b2 mRNA vaccine and a clear picture of Henoch Schönlein purpura 5 days after administration of the second dose of the same vaccine.

Conclusion

To our knowledge, this is the first description of a pediatric patient with Henoch-Schönlein purpura occurring in association with vaccination against COVID-19.

Cervical Staphylococcus aureus Infection after Receiving the Third Dose of COVID-19 Vaccination: A Case Report

Introduction: Vaccination is one of the most effective ways to control the COVID-19 pandemic. However, as the number of people vaccinated against COVID-19 continues to increase, there are more reports on the safety of vaccines. So far, there have been no reported cases of spinal infection associated with COVID-19 vaccination. Recently, we admitted a patient who developed cervical Staphylococcus aureus infection resulting in high paraplegia after receiving the third dose of COVID-19 vaccine when the symptoms of cold did not completely disappear. Case presentation: The patient was a 70-year-old man who received the third injection of COVID-19 vaccine when the cold symptoms were not completely gone. On the day after the injection, the patient developed severe neck and shoulder pain, accompanied by numbness and fatigue in the limbs. MRI examination of the cervical spine on day 6 after vaccination showed no obvious signs of infection. The patient had progressive weakness in the extremities. On the ninth day after vaccination, the patient developed paralysis of both lower limbs and significant sensory loss. Cervical abscess and cervical spinal cord injury were considered for cervical CT and MRI examination on the 15th day after vaccination. We used an anterior approach to remove as much of the lesion as possible. Staphylococcus aureus was detected and antibiotic treatment was continued after surgery. The patient’s pain symptoms were significantly relieved, which prevented the abscess from further pressing the spinal cord and provided possible conditions for the recovery of neurological function in the later stage. Conclusion: This case is the first reported cervical Staphylococcus aureus infection resulting in high paraplegia after receiving the third dose of COVID-19 vaccine with low immunity. This case raises awareness of this rare but potentially life-threatening adverse reaction, and reminds people to hold off when their immune system is weakened.

Reply to: "Herpes zoster seven days after SARS-CoV-2 vaccination in a patient with ankylosing spondylitis under adalimumab" by Josef Finsterer

Not available.

A Randomized, Single Centered, Parallel and Open labelled Interventional Study on Effectiveness of Clinical Pharmacists on Adverse Event Following Immunization (AEFI) in Pediatric Population

BACKGROUND

Adverse events are a major threat to any immunization programs, which in turn have proven to be a boon for developing nations like India. Hindering factors, such as inadequate knowledge, inappropriate attitude, incorrect practices, etc., of the guardian affect the vaccination rate.

AIM

This study aims to assess the effectiveness of clinical pharmacist intervention on an adverse event following immunization in the pediatric population receiving immunization.

MATERIALS AND METHODS

Pediatric subjects <5 yrs of both genders receiving immunization in a tertiary care hospital during the period of 8 months were considered. Subjects were randomized into control and interventional groups. Pharmaceutical intervention was done in interventional group in the form of patient counselling, and a patient information leaflet. Adverse event following immunization was recorded and analysed for both groups along with Knowledge, Attitude, and Practice scores of guardians' pre and post intervention through customized data collection forms. Microsoft excel and statistical software SPSS IBM version 22 was used to analyse the data.

RESULTS

The study was conducted on a total of 88 subjects (n) in which 79 were <2 years, 1 and 8 were between 2-4 years and 4-5 years respectively. 49 Forty-ninesubjects (55.69%) were female, while 39 were male (44.31%) with a response and completion rate of 91.66%. 97.7% subjects received Bacillus Calmette-Guerin vaccination (majority), while 8.88% received pneumococcal special vaccine (minority). Adverse event following immunization was recorded in 31(35.22%) cases. Knowledge, Attitude and Practice scores increased by 42.17%, 52% and 12.67%, respectively in guardians after clinical pharmacist intervention.

CONCLUSION

This studydemonstrates that educational inputs, awareness programs, and proper medical professional intervention can act as a helping factor to fight against AEFI and towards the success of an immunization program.

Can SARS-CoV-2 vaccine increase the risk of reactivation of Varicella zoster? A systematic review

INTRODUCTION

Although the COVID-19 vaccination is deemed safe, exact incidence and nature if adverse effects, particularly dermatological ones, are still unknown.

OBJECTIVE

To describe the demographic, clinical, morphological characteristics, outcomes, and timing of development of herpes zoster to the various COVID-19 vaccines. And to identify on whether COVID-19 vaccine has temporal relationship between development of herpes zoster (HZ).

METHODS

We have performed a systemic review of articles from PubMed and Embase using MeSH and keywords like "Shingles," "Herpes zoster," "Varicella zoster," "COVID-19," "Vaccine," "SARS-CoV-2." No filters including country of publication, language, type of articles were applied. Individual case report references were filtered for any pertinent cases.

RESULTS

A total of 54 cases consisting of 27 male and 27 female patients have been reported. There were cases with known risk factors for herpes zoster, which included age more than 50 years (n = 36), immunological disorders (n = 10), chronic disease (n = 25), metabolic disorder (n = 13), malignancy (n = 4), and psychiatric disorder (n = 2). The mean (SD) period between development of herpes zoster and COVID-19 vaccination was 7.64 (6.92) days. Majority of the cases were from the high-income and/or middle-income countries. 86.27% of the cases of HZ were reported due to mRNA vaccine. Thirty-six patients 36/45 (80%) developed herpes zoster following the priming dose of COVID-19 vaccine among those who received mRNA vaccine.

CONCLUSION

We could not establish definite link but there may be possible association between COVID-19 vaccine and shingles. Large-scale studies may help to understand the cause-effect relationship.

Tolerability of MenACWY-TT vaccination in adolescents in the Netherlands; a cross-sectional study

BACKGROUND

In 2018, meningococcal ACWY-TT vaccine (MenACWY-TT) was offered to adolescents in the Netherlands within the National Immunization Programme at 14 years of age. A questionnaire study assessed the tolerability of this vaccine.

METHODS

Five thousand adolescents were invited to participate and to fill in two questionnaires about systemic events in the week before vaccination and local reactions and systemic events in the week after vaccination. Frequencies of local and systemic adverse events in the week after vaccination were calculated. Association between the occurrence of systemic symptoms in the week before and after the vaccination was tested by using generalized mixed models (GLMM).

RESULTS

Of all adolescents, 139 returned one or both questionnaires. Any local reaction within 7 days after vaccination was reported by 55.6% of the adolescents. Pain (50%) and reduced use of the injected arm (21.3%) were most often reported. Any systemic event was reported by 67.6% of the participants, with myalgia as the most often reported event (37.0%). Compared with the week before vaccination, there were no increased odds of experiencing systemic symptoms in the week after vaccination (OR 0.95; 95%CI 0.40-2.27).

CONCLUSIONS

After vaccination with MenACWY-TT vaccine, most adolescents reported one or more adverse events, which were mostly mild and transient. Systemic symptoms were not reported more often in the week after compared to the week before vaccination. Unfortunately, due to a low response rate we were not able to detect the absolute elevated risks the sample size calculation was based on. However, despite limited data, our results are in line with results from prelicensure data, and indicate that MenACWY-TT vaccination is well tolerated in adolescents.

Safety and Tolerability of the BNT162b2 mRNA COVID-19 Vaccine in Dialyzed Patients. COViNEPH Project

Background and Objectives: The Pfizer-BioNTech (BNT162b2) COVID-19 mRNA vaccine has demonstrated excellent efficacy and safety in phase 3 trials. However, no dialyzed patients were included, and therefore safety data for this patient group is lacking. The aim of the study was to assess the safety and tolerances of vaccinations with BNT162b2 performed in chronically dialyzed patients. Materials and Methods: We performed a prospective cohort study including a group of 190 dialyzed patients (65% male) at median age 68.0 (55-74) years. 169 (89.0%) patients were treated with hemodialysis and 21 (11.0%) with peritoneal dialysis. The control group consisted of 160 people (61% male) without chronic kidney disease at median age 63 (range 53-77) years. Both groups were vaccinated with BNT162b2 with a 21-day interval between the first and the second dose. Solicited local and systemic reactogenicity, unsolicited adverse events and antipyretic and pain medication use were assessed with a standardized questionnaire. The toxicity grading scales were derived from the FDA Center for Biologics Evaluation and Research guidelines. Results: 59.8% (dose 1), 61.4% (dose 2) and 15.9% (dose 1), 29.4% (dose 2) dialyzed patients reported at least one local and one systemic reaction respectively within seven days after the vaccination. Many local and systemic solicited reactions were observed less frequently in dialyzed patients than in the age and sex matched control group and much less frequently than reported in the pivotal study. They were mostly mild to moderate, short-lived, and more frequently reported in younger individuals and women. No related unsolicited adverse events were observed. Conclusions: We have shown here that BNT162b2, an mRNA vaccine from Pfizer-BioNTech against SARS-COV-2 is safe and well-tolerated by dialyzed patients. The results can be useful for the nephrological community to resolve patients' doubts and reduce their vaccine hesitancy.

Neurologic Disease after Yellow Fever Vaccination, São Paulo, Brazil, 2017-2018

Disease should be diagnosed by using the Brighton Collaboration case definitions and cerebrospinal fluid IgM reactivity.

Yellow fever (YF) vaccine can cause neurologic complications. We examined YF vaccine–associated neurologic disease reported from 3 tertiary referral centers in São Paulo, Brazil, during 2017–2018 and compared the performance of criteria established by the Yellow Fever Vaccine Working Group/Centers for Disease Control and Prevention and the Brighton Collaboration. Among 50 patients who met inclusion criteria, 32 had meningoencephalitis (14 with reactive YF IgM in cerebrospinal fluid), 2 died, and 1 may have transmitted infection to an infant through breast milk. Of 7 cases of autoimmune neurologic disease after YF vaccination, 2 were acute disseminated encephalomyelitis, 2 myelitis, and 3 Guillain-Barré syndrome. Neurologic disease can follow fractional vaccine doses, and novel potential vaccine-associated syndromes include autoimmune encephalitis, opsoclonus-myoclonus-ataxia syndrome, optic neuritis, and ataxia. Although the Brighton Collaboration criteria lack direct vaccine causal assessment, they are more inclusive than the Centers for Disease Control and Prevention criteria.

Active Vaccine Safety Surveillance: Global Trends and Challenges in China

Importance. The great success in vaccine-preventable diseases has been accompanied by vaccine safety concerns. This has caused vaccine hesitancy to be the top 10 in threats to global health. The comprehensive understanding of adverse events following immunization should be entirely based on clinical trials and postapproval surveillance. It has increasingly been recognized worldwide that the active surveillance of vaccine safety should be an essential part of immunization programs due to its complementary advantages to passive surveillance and clinical trials.Highlights. In the present study, the framework of vaccine safety surveillance was summarized to illustrate the importance of active surveillance and address vaccine hesitancy or safety concerns. Then, the global progress of active surveillance systems was reviewed, mainly focusing on population-based or hospital-based active surveillance. With these successful paradigms, the practical and reliable ways to create robust and similar systems in China were discussed and presented from the perspective of available databases, methodology challenges, policy supports, and ethical considerations.Conclusion. In the inevitable trend of the global vaccine safety ecosystem, the establishment of an active surveillance system for vaccine safety in China is urgent and feasible. This process can be accelerated with the consensus and cooperation of regulatory departments, research institutions, and data owners.

Reactivation of Varicella Zoster Virus after Vaccination for SARS-CoV-2

Seven immunocompetent patients aged > 50 years old presented with herpes zoster (HZ) infection in a median of 9 days (range 7-20) after vaccination against SARS-CoV-2. The occurrence of HZ within the time window 1-21 days after vaccination defined for increased risk and the reported T cell-mediated immunity involvement suggest that COVID-19 vaccination is a probable cause of HZ. These cases support the importance of continuing assessment of vaccine safety during the ongoing massive vaccination for the COVID-19 pandemic and encourage reporting and communication of any vaccination-associated adverse event.

Novel vaccine design based on genomics data analysis: A review

Modification of pathogenic strains with the passage of time is responsible for evolution in the timeline of vaccine development for last 30 years. Recent advancements in computational vaccinology on the one hand and genome sequencing approaches on the other have generated new hopes in vaccine development. The aim of this review was to discuss the evolution of vaccines, their characteristics and limitations. In this review, we highlighted the evolution of vaccines, from first generation to the current status, pointing out how different vaccines have emerged and different approaches that are being followed up in the development of more rational vaccines against a wide range of diseases. Data were collected using Google Scholar, Web of Science, Science Direct, Web of Knowledge, Scopus and Science Hub, whereas computational tools such as NCBI, GeneMANIA and STRING were used to analyse the pathways of vaccine action. Innovative tools, such as computational tools, recombinant technologies and intra-dermal devices, are currently being investigated in order to improve the immunological response. New technologies enlightened the interactions of host proteins with pathogenic proteins for vaccine candidate development, but still there is a need of integrating transcriptomic and proteomic approaches. Although immunization with genomics data is a successful approach, its advantages must be assessed case by case and its applicability depends on the nature of the agent to be immunized, the nature of the antigen and the type of immune response required to achieve effective protection.

Immunogenicity and safety of a live herpes zoster vaccine in hematopoietic stem cell transplant recipients

BACKGROUND

Herpes zoster (HZ) infection of hematopoietic stem cell transplant (HSCT) patients is of clinical concern. Vaccination could help restore immunity to varicella zoster virus (VZV); however, temporal changes in immunogenicity and safety of live HZ vaccines after HSCT is still unclear. The aim of this study was to elucidate the temporal immunogenicity and safety of the HZ vaccine according to time since HSCT and to determine optimal timing of vaccination.

METHODS

Live HZ vaccine was administered to patients 2-5 years or > 5 years post-HSCT. Control groups comprised patients with a hematologic malignancy who received cytotoxic chemotherapy and healthy volunteers. Humoral and cellular immunogenicity were measured using a glycoprotein enzyme-linked immunosorbent assay (gpELISA) and an interferon-γ (IFN-γ) enzyme-linked immunospot (ELISPOT) assay. Vaccine-related adverse events were also monitored.

RESULTS

Fifty-six patients with hematologic malignancy (41 in the HSCT group and 15 in the chemotherapy group) along with 30 healthy volunteers were enrolled. The geometric mean fold rises (GMFRs) in humoral immune responses of the 2-5 year and > 5 year HSCT groups, and the healthy volunteer group, were comparable and significantly higher than that of the chemotherapy group (3.15, 95% CI [1.96-5.07] vs 5.05, 95% CI [2.50-10.20] vs 2.97, 95% CI [2.30-3.83] vs 1.42, 95% CI [1.08-1.86]). The GMFR of cellular immune responses was highest in the HSCT 2-5 year group and lowest in the chemotherapy group. No subject suffered clinically significant adverse events or reactivation of VZV within the follow-up period.

CONCLUSION

Our findings demonstrate that a live HZ vaccine is immunogenic and safe when administered 2 years post-HSCT.

Adverse events following measles-mumps-rubella-varicella vaccine: an independent perspective on Italian pharmacovigilance data

Vaccine surveillance programs are crucial for the analysis of the vaccine’s safety profile and the guidance of health policies. The Epidemiological Observatory of the Italian Apulia Region carried out an active surveillance program of adverse effects following immunization (AEFI) after the first dose of the measles-mumps-rubella-varicella (MMRV) vaccine, finding 462 AEFIs per 1000 doses, with 11% rated serious. Applying the World Health Organization (WHO) causality assessment algorithm, 38 serious AEFIs/1000 enrolled were classified as ‘consistent causal associations’ with MMRV immunization. Severe hyperpyrexia, neurological symptoms and gastrointestinal diseases occurred in 38, 20 and 15 cases/1000 enrolled, respectively. A projection of such AEFIs in an Italian birth cohort would give tens of thousands of serious AEFIs. These incidence data are much greater than the incidence of serious AEFIs reported by the Italian Medicines Agency (AIFA) for years 2017 and 2018, mainly based on passive (or mixed) pharmacovigilance. In a previous epidemiological study in the same Italian Region, during an eight year passive surveillance, the reporting rate of serious AEFI was 0.06/1000 doses, and no cases of febrile seizures were detected applying the WHO algorithm. Taken together, the data suggest that passive pharmacovigilance is utterly inadequate to document the real incidence of serious AEFIs and that current methods of assessing causality may be questioned. Active surveillance programs are required in representative population samples, with results presented separately from those of spontaneous reporting, and causality assessment should be performed carefully and using a correct technique for AEFIs presenting as complex and multifactorial diseases, like those with serious neurologic disorders.

Adverse events following measles-mumps-rubella-varicella vaccine: an independent perspective on Italian pharmacovigilance data

Vaccine surveillance programs are crucial for the analysis of the vaccine’s safety profile and the guidance of health policies. The Epidemiological Observatory of the Italian Apulia Region carried out an active surveillance program of adverse effects following immunization (AEFI) after the first dose of the measles-mumps-rubella-varicella (MMRV) vaccine, finding 462 AEFIs per 1000 doses, with 11% rated serious. Applying the World Health Organization (WHO) causality assessment algorithm, 38 serious AEFIs/1000 enrolled were classified as ‘consistent causal associations’ with MMRV immunization. Severe hyperpyrexia, neurological symptoms and gastrointestinal diseases occurred in 38, 20 and 15 cases/1000 enrolled, respectively. A projection of such AEFIs in an Italian birth cohort would give tens of thousands of serious AEFIs. These incidence data are much greater than the incidence of serious AEFIs reported by the Italian Medicines Agency (AIFA) for years 2017 and 2018, mainly based on passive (or mixed) pharmacovigilance. In a previous epidemiological study in the same Italian Region, during an eight year passive surveillance, the reporting rate of serious AEFI was 0.06/1000 doses, and no cases of febrile seizures were detected applying the WHO algorithm. Taken together, the data suggest that passive pharmacovigilance is utterly inadequate to document the real incidence of serious AEFIs and that current methods of assessing causality may be questioned. Active surveillance programs are required in representative population samples, with results presented separately from those of spontaneous reporting, and causality assessment should be performed carefully and using a correct technique for AEFIs presenting as complex and multifactorial diseases, like those with serious neurologic disorders.

Vaccine-Associated Neurological Adverse Events: A Case Report and Literature Review

Vaccination is an effective strategy to reduce the burden of preventable illness. However, many clinical reports revealed that various vaccinations may associate with neurological disorders, mainly including autoimmune disease, febrile seizure, and vaccine-associated paralytic poliomyelitis (VAPP). Although more and more reports revealed that part of the above post-vaccine neurological disorders is not directly related to vaccination, it may be merely a coincidence. However, these reports may increase the hesitancy on vaccination for the public population and influence the coverage of vaccination. In this report, we described a child with acute flaccid paralysis possibly caused by a poliovirus vaccine. To provide feasible ways to realize or reduce the risk of neurological adverse events caused by vaccines, we further provide a mini-review of the literature of vaccination associated with neurological adverse events. This revealed that oral poliomyelitis vaccine use exclusively and type 2 serotype poliomyelitis vaccine virus were the risk factors for VAPP. The combination vaccine was associated with an increased risk of ADEM and FS following immunization when compared with the administration of vaccines separately. Even though cases have been reported that vaccination may be a trigger of anti-NMDARe and GBS, there is no direct evidence to prove that vaccination increased the risk of GBS and anti-NMDARe.

Ten years of vaccinovigilance in Italy: an overview of the pharmacovigilance data from 2008 to 2017

Reporting and analysis of Adverse Events Following Immunization (AEFIs) are the cornerstones of vaccine safety surveillance prompting causality assessment and signal detection. This paper describes the impact of the Italian Pharmacovigilance System of vaccines over a 10-year period (2008–2017). The reporting rate (RR) per all distributed dose was calculated. Serious AEFIs and causality assessments for fatal cases were described. The main results from signal detection were reported. During the study period, 46,430 AEFIs were reported with an overall RR of 17.2 per 100,000 distributed doses. Italy showed the highest number of reports among European countries. Only 4.4% of the reports came from citizens. Of the total, 12.7% were classified as serious with a RR over the study period of 2.20 per 100,000 distributed doses. They were mainly related to hyperpyrexia and usually had a positive outcome. Fatal outcomes were reported in 0.3% of the cases and were primarily associated with the influenza vaccine in elderly patients. None of these outcomes had a consistent causal association with the vaccination. Febrile convulsions by the measles, mumps, rubella and varicella vaccines and intussusception by the rotavirus vaccine were among the highlighted signals. The reporting rate and the analysis of serious events from 10 years support the good risk/benefit profiles of vaccines.

Review of pediatric encephalitis and encephalopathy cases following immunization reported to the Canadian Immunization Monitoring Program Active (IMPACT) from 1992 to 2012

BACKGROUND

Neurological adverse events following immunization (AEFI) remain poorly characterized. Our objective was to describe pediatric acute and chronic encephalopathy and encephalitis cases following immunization reported via active sentinel surveillance from 1992 to 2012.

METHODS

This case series provides a descriptive analysis of encephalopathy/encephalitis admissions reported to the Canadian Immunization Monitoring Program ACTive (IMPACT). Acute cases were reported if symptom onset (seizures, decreased level of consciousness, change in mental status) occurred 0-7 days after tetanus or pertussis-containing vaccines, 0-15 days after other inactivated vaccines, or 5-30 days after live vaccines. Chronic cases of subacute sclerosing panencephalitis or subacute progressive rubella encephalitis were reported at any interval after vaccination. Clinical data were examined to identify possible causes for encephalopathy/encephalitis other than vaccination.

RESULTS

Sixty-one cases of encephalopathy/encephalitis following immunization were reported to IMPACT over 21 years; 57 (93.4%) were classified as acute and 4 (6.6%) were chronic cases of subacute sclerosing panencephalitis. Most patients (73.8%) were previously healthy and immunocompetent. The vaccines most frequently administered prior to presentation were diphtheria-tetanus-pertussis, measles-mumps-rubella, and influenza. At discharge, 38 patients (62.3%) had normal neurological status or were expected to recover. Forty patients (70.2%) with acute encephalopathy/encephalitis had a more likely alternate etiology besides vaccination based on neuroimaging, symptoms suggestive of infection, laboratory-confirmed non-vaccine-related infection, or clinical diagnosis. No cases of encephalitis were causally associated with pertussis or influenza vaccines. Two patients (50%) with subacute sclerosing panencephalitis had known wild-type measles infection prior to immunization. Three deaths were reported during hospitalization (4.9%); all were acute encephalitis/encephalopathy cases and none were confirmed to be vaccine-related.

CONCLUSIONS

Encephalopathy/encephalitis following immunization remains a rare but serious adverse event. Most cases had another more likely etiology than vaccination. Continued monitoring and analysis of AEFI is paramount to ensure the safety of immunization programs.

The state of vaccine safety science: systematic reviews of the evidence

This Review updates the scientific evidence assessing possible causal associations of adverse events following immunisation (AEFI) compiled in the 2012 report from the Institute of Medicine and the 2014 report from the Agency for Healthcare Research and Quality. For 12 of 46 AEFI examined, a causal relationship has been established with at least one vaccine currently routinely recommended to the general USA population: anaphylaxis, arthralgia or arthritis (mild, acute, and transient, not chronic), deltoid bursitis (when vaccine is administered improperly), disseminated varicella infection (in immune deficient individuals for whom the varicella vaccine is contraindicated), encephalitis, febrile seizures, Guillain-Barré syndrome, hepatitis (in immune deficient individuals for whom the varicella vaccine is contraindicated), herpes zoster, immune thrombocytopenic purpura, meningitis, and syncope. Other than mild acute and transient arthralgia or arthritis, which is very common in adult women after rubella vaccine, these adverse reactions are rare or very rare. Vaccines have an excellent safety profile overall and provide protection against infectious diseases to individuals and the general population.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that can explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents some concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to vaccine injury compensation programs. The majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that might explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents several concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. Given these inadequacies in the evaluation of multifactorial diseases, the WHO guidelines need to be reevaluated and revised. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.

Fatal outcomes following immunization errors as reported to the EudraVigilance: A case series

BACKGROUND

Serious adverse reactions after immunization are rare but do occur. In very rare instances, cases with fatal outcome have been reported. These reports can have a huge impact and even more so when due to an immunization error. The aim of this study is to systematically review immunization errors with fatal outcomes in EudraVigilance.

METHODS

This was a case-series analysis of Individual Case Safety Reports (ICSRs) reporting immunization errors and a fatal outcome. To determine the level of certainty of a causal association between the immunization errors and fatal outcomes two independent reviewers assessed all ICSRs using the WHO tool "Causality assessment of an Adverse Event Following Immunization (AEFI)". In accordance with the tool, the ICSRs were classified as consistent, indeterminate, inconsistent/coincidental, or unclassifiable. In addition, we estimated the contribution of reported errors to the fatal outcomes as large, moderate, small, none, or unclassifiable using a classification developed for this study.

RESULTS

A total of 154 ICSRs met the inclusion criteria. Vaccines reported most frequently were pneumococcal (33), rabies (27) and influenza vaccines (24). Most frequently reported errors were non-compliance with recommended schedules of immunization (63). The most frequently reported vaccine-error combination was rabies vaccines and non-compliance with a recommended schedule of immunization (23). Twelve cases were classified as consistent with causal association and had a large error contribution. These cases concerned a cluster of six cases reporting incorrect handling of multi-dose vials containing measles vaccine and six cases reporting administration of live-attenuated vaccines to immunocompromised patients.

DISCUSSION

In this study, we showed that fatal outcomes following immunization errors are very rare. Four key issues were the importance of: (1) quality control of multi-dose vaccines, (2) screening patients for immunocompromising factors, (3) education on the importance of adherence, and (4) measures to improve distinction between vaccines and medicines.

Primary ovarian insufficiency and human papilloma virus vaccines: a review of the current evidence

Human papilloma virus is the primary causative agent for cervical cancer, and vaccination is the primary means of preventing anogenital cancers caused by human papilloma virus infection. Despite the availability of human papilloma virus vaccines for more than a decade, coverage rates lag behind those for other vaccines. Public concerns regarding safety of human papilloma virus vaccines have been identified as an important barrier to vaccination, including concerns that the human papilloma virus vaccine may cause primary ovarian insufficiency, driven in part by isolated reports of ovarian failure following the human papilloma virus vaccine. We summarize published peer-reviewed literature on human papilloma virus vaccines and primary ovarian insufficiency, reviewing information contained in the case reports and series. Healthcare providers should address any patient concerns about primary ovarian insufficiency and the human papilloma virus vaccine by acknowledging the case reports but noting the lack of association found in a recently published epidemiologic study of approximately 60,000 female individuals. Current evidence is insufficient to suggest or to support a causal relationship between human papilloma virus vaccination and primary ovarian insufficiency.

Prevalence and types of vaccination errors from 2009 to 2018: A systematic review of the medical literature

INTRODUCTION

Vaccination practices and the programmatic factors that influence them are essential for public health. Several barriers impact vaccination efforts, including vaccination errors, which pose the risk of reduced population-wide vaccination efficacy and individual adverse drug events. This study aimed to define the prevalence of vaccination errors documented in English language medical literature between 2009 and 2018 and to identify the common types of errors that occurred during this period.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. The study protocol was registered with the International Prospective Register of Systematic Reviews prior to research activities. The Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, Google Scholar, ProQuest Central, PubMed, Scopus, and Web of Science were searched using predetermined search terms. Included data were from primary studies or retrospective analyses that assessed the prevalence and/or type of vaccination errors and that were peer-reviewed, conducted between 2009 and 2018, and published in English. Data were extracted using the Cochrane Data Extraction and Assessment Template and assessed using the Appraisal tool for Cross-Sectional Studies. Pooled vaccination error prevalence was then calculated.

RESULTS

Of the 1310 independent records that were identified and screened, 17 studies from five countries met all inclusion criteria. Pooled vaccination error prevalence was calculated to be 1.15 per 10,000 vaccine doses (range, 0.005-141.69 per 10,000 doses). The most commonly reported vaccination errors were "wrong vaccine administered" and "off-schedule administration."

CONCLUSIONS

International rates of vaccination error reporting remain low, with few reports of significant adverse reactions. Vaccination programs should consider the impact of vaccination errors on individual and population health, particularly focusing on the impact of "wrong vaccine" administration. Continued monitoring and promotion of error reporting will enable further understanding of this topic.

Immunogenicity of Influenza Vaccination in Patients with Cancer Receiving Immune Checkpoint Inhibitors

Among prospectively enrolled adult patients with cancer receiving immune checkpoint inhibitors (ICIs; n = 46) or cytotoxic agents (n = 90), seroprotection and seroconversion rates after seasonal quadrivalent influenza vaccinations were higher with ICI than with cytotoxic chemotherapy. These results support annual influenza vaccinations for cancer patients receiving ICIs.

Clinical Trials Registration clinicaltrials.gov (NCT03590808).

Challenges in evaluating post-licensure vaccine safety: observations from the Centers for Disease Control and Prevention

Introduction: Vaccination is one of the most successful and cost-effective public health interventions. Although vaccines undergo extensive safety and efficacy evaluations prior to licensure, vaccine safety assessment post-licensure is essential for detecting rare and longer-term adverse events (AEs) and maintaining public confidence in vaccines and recommended immunization programs. Despite the proven effect of vaccines to save lives and prevent disease and overwhelming evidence of vaccines' safety and societal benefit, like any drug, no vaccine can be considered as completely safe and completely effective. New vaccines continue to be introduced and require rapid safety assessment post-licensure through pharmacovigilance reports as well as epidemiologic studies to investigate any potential safety signals.Areas covered: We discuss selected challenges for conducting pharmacovigilance and epidemiologic studies of AEs after vaccination in the United States using the post-licensure safety surveillance infrastructure of the Centers for Disease Control and Prevention (CDC).Expert opinion: The availability of specific post-licensure surveillance systems to monitor and study AEs after vaccination, such as the Vaccine Adverse Event Reporting System, the Vaccine Safety Datalink, and the Clinical Immunization Safety Assessment Project, each with its unique set of strengths and limitations, provide a harmonized and supportive approach to meet several of these barriers.

Vaccines Safety in Children and in General Population: A Pharmacovigilance Study on Adverse Events Following Anti-Infective Vaccination in Italy

Background: The concern for adverse events following immunization (AEFI) and anti-vaccination movements that lacked scientific evidence-based supports may reduce vaccine uptake in the general population. Thus, the aims of the present study were to characterize AEFI in general population (all age groups), in terms of frequency, preventability, and seriousness and to define predictors of their seriousness in children.

Methods: A retrospective study was performed on suspected AEFI reports for children and adults who received any form of vaccinations, collected in Tuscany, Italy, between 1 January and 31 December 2017. Patients’ characteristics, suspected vaccines, and AEFI description were collected. Causality and preventability were assessed using WHO and Schumock and Thornton algorithms, respectively. Logistic regression was used to estimate the reporting odds ratios of potential predictors of AEFI seriousness in children.

Results: A total of 223 suspected AEFI reports were collected, and the majority of them were defined as non-serious (76.7%). Reports were mostly related to one vaccine, and to a median of two to five strains/toxoids. The total number of simultaneously administered strains/toxoids and the presence of allergens did not correlate with AEFI seriousness. Considering vaccines with a high number of administered doses (≥60,000 doses), the rates estimated for serious AEFI reports were always very low, ranging between 0.01 and 0.2/1,000 doses. Twenty-four vaccines (8,993 doses) were not related to any AEFI.

Conclusion: Results of present study showed that AEFI were very rare; the vast majority of them was non-serious and, despite the claims of anti-vaccination movements, the simultaneous administration of vaccines was safe and did not influence the risk of reporting a serious AEFI, particularly in children.

An approach for preparing and responding to adverse events following immunization reported after hepatitis B vaccine birth dose administration

The success of immunization programs in lowering the incidence of vaccine preventable diseases (VPDs) has led to increased public attention on potential health risks associated with vaccines. As a result, a scientifically rigorous response to investigating reported adverse events following immunization (AEFI) and effective risk communications strategies are critical to ensure public confidence in immunization. Globally, an estimated 257 million people have chronic hepatitis B virus (HBV) infection, which causes more than 686,000 premature deaths from liver cancer and cirrhosis. Hepatitis B vaccination is the most effective way to prevent mother-to-child transmission of HBV infection, especially when a timely birth dose is given within 24 h of birth. However, an infant's risk of dying is highest in the neonatal period, and thus, administering HepB-BD within 24 h of birth overlaps with the most fragile period in an infant's life. A working group formed in July 2016 following the publication of the case reports of the effects on vaccination coverage of media reports of infant deaths after HepB-BD administration in China and Vietnam. The goal of the working group was to create a framework and describe best practices for preparing for and responding to AEFI reported after HepB-BD administration, using existing resources. The framework includes six steps, including three preparation steps and three response steps. This document is written for national and regional immunization program staff. Prior to using the framework for preparation and response to AEFIs reported after HepB-BD administration, staff members should be familiar with how AEFI are detected, reported, and investigated in the country. The document might also be of interest to national regulatory staff members who monitor vaccine safety within the country.

Immunogenicity and safety of a novel recombinant protective antigen anthrax vaccine (GC1109), a randomized, single-blind, placebo controlled phase II clinical study

BACKGROUND

The demand on effective and safe anthrax vaccine is increasing as a part of the preparedness for possible bioterrorism in the future. We performed a randomized, single-blind, placebo controlled phase II clinical study to evaluate the immunogenicity and safety of a novel recombinant protective antigen (rPA) anthrax vaccine, GC1109, in healthy adult volunteers.

METHODS

Participants were randomized to experiment groups (0.3 mL, 0.5 mL, and 1.0 mL of GC1109) or placebo group (normal saline 0.5 mL) in 2:2:2:1 ratio. They received respective vaccines intramuscularly at 0, 4 and 8 weeks. Immunogenicity was evaluated by seroconversion rate and geometric mean titer (GMT) of lethal toxin neutralizing assay (TNA) and anti-PA IgG by ELISA. Safety was assessed by laboratory tests, and solicited and unsolicited adverse events on diary cards.

RESULTS

30, 29, 30 participants were randomized to 0.3, 0.5, and 1.0 mL of GC1109 groups, respectively, while 15 to placebo group. 92 participants received all three doses. In per-protocol analysis, TNA GMTs at week 12 were 296.5, 285.2, and 433.2 in the three groups, respectively. Seroconversion rates measured by ELISA were 100% at week 12 in the three groups. Local and systemic vaccine-related adverse events were frequent; however, most of them were mild, and no serious events were observed.

CONCLUSIONS

A new rPA anthrax vaccine GC1109 was immunogenic after three doses of intramuscular administration, and was well-tolerated.

Brazilian recommendations on the safety and effectiveness of the yellow fever vaccination in patients with chronic immune-mediated inflammatory diseases

BACKGROUND

In Brazil, we are facing an alarming epidemic scenario of Yellow fever (YF), which is reaching the most populous areas of the country in unvaccinated people. Vaccination is the only effective tool to prevent YF. In special situations, such as patients with chronic immune-mediated inflammatory diseases (CIMID), undergoing immunosuppressive therapy, as a higher risk of severe adverse events may occur, assessment of the risk-benefit ratio of the yellow fever vaccine (YFV) should be performed on an individual level. Faced with the scarcity of specific orientation on YFV for this special group of patients, the Brazilian Rheumatology Society (BRS) endorsed a project aiming the development of individualized YFV recommendations for patients with CIMID, guided by questions addressed by both medical professionals and patients, followed an internationally validated methodology (GIN-McMaster Guideline Development). Firstly, a systematic review was carried out and an expert panel formed to take part of the decision process, comprising BRS clinical practitioners, as well as individuals from the Brazilian Dermatology Society (BDS), Brazilian Inflammatory Bowel Diseases Study Group (GEDIIB), and specialists on infectious diseases and vaccination (from Tropical Medicine, Infectious Diseases and Immunizations National Societies); in addition, two representatives of patient groups were included as members of the panel. When the quality of the evidence was low or there was a lack of evidence to determine the recommendations, the decisions were based on the expert opinion panel and a Delphi approach was performed. A recommendation was accepted upon achieving ≥80% agreement among the panel, including the patient representatives. As a result, eight recommendations were developed regarding the safety of YFV in patients with CIMID, considering the immunosuppression degree conferred by the treatment used. It was not possible to establish recommendations on the effectiveness of YFV in these patients as there is no consistent evidence to support these recommendations.

CONCLUSION

This paper approaches a real need, assessed by clinicians and patient care groups, to address specific questions on the management of YFV in patients with CIMID living or traveling to YF endemic areas, involving specialists from many areas together with patients, and might have global applicability, contributing to and supporting vaccination practices. We recommended a shared decision-making approach on taking or not the YFV.

Revisiting Influenza Vaccination Exemption

Serious adverse events after immunizations are rare. We review the case of a man who, 50 years earlier, experienced a serious adverse neurologic event 2 weeks after receiving influenza vaccine. He had received no subsequent seasonal influenza vaccinations, but after the risks and benefits were considered, he was vaccinated without adverse event that season.

Causality in Pharmacoepidemiology and Pharmacovigilance: a theoretical excursion

The article presents some considerations about causality in Pharmacoepidemiology and Pharmacovigilance. To begin, we provide a brief introduction about the importance of the issue, noting that the understanding of causal relationships is considered one of science's greatest achievements and has been, over time, a continuous and central concern of philosophers and epidemiologists. Next, we describe definitions and types of causes, demonstrating their influences on pharmacoepidemiological thought. After that, we present Rothman's multi-causal model as one of the founding explanations of multiple causality and the issue of causality assessment. We conclude with some comments and reflections on causality from the perspective of health surveillance, particularly with regard to regulations on pharmacovigilance.