Adverse events following immunization: perception and evidence

Vaccine Production Process: How Much Does the General Population Know about This Topic? A Web-Based Survey

Background: Vaccine hesitancy has been recognized as a major global health threat by the World Health Organization. Many studies have investigated vaccine safety as a determinant for vaccine hesitancy; however, not much attention has been paid to vaccine production and quality control during the vaccine production process or whether knowledge about this topic may influence vaccine confidence. The aim of this study was to characterize the common knowledge about the vaccine production process. Methods: A freely accessible online questionnaire was developed on Google Modules and disseminated through social networks. A descriptive analysis of the collected answers was performed, and the chi-square test was used to assess significant differences for the sociodemographic characteristics of the study population (age, gender, work or education and training in the healthcare setting, minor offspring). A binary logistic regression model was performed considering these socio-demographic categories as independent variables. Results: The number of collected questionnaire was 135. Most of the participants (127/135, 94.1%) were aware that quality control measures are carried out during manufacturing, although some knowledge gaps emerged in specific aspects of the vaccine production process, without statistically significant differences between age groups. Working in the healthcare setting or being educated in healthcare may be considered predictors for a better understanding that more than 50% of the production time is spent on quality control (AOR = 3.43; 95% CI: 1.84–8.14, p = 0.01) and that considering quality control performed during the vaccine production process is adequate for avoiding contamination (AOR = 7.90; 95% CI: 0.97–64.34; p = 0.05). Conclusions: This study allowed for a characterization of common knowledge about the vaccine production process. It highlighted the need to implement specific strategies to spread correct information about the vaccine production process. This study may contribute to increased confidence and trust in vaccines and vaccination among the general population.

Is science for atheists? Perceived threat to religious cultural authority explains U.S. Christians' distrust in secularized science

A history of perceived conflict between religion and science persists in the U.S. "culture wars" that juxtapose religious and secular worldviews. As modern societies grow increasingly secular, religion is often deemed an impediment to science-based policy-making, whereas science is increasingly associated with atheism. In the present research, we addressed how perceived science-atheism associations affect U.S. Christians' attitudes toward science. In study 1, participants' own estimates of atheists' prevalence in science uniquely predicted distrust in science, and study 2 revealed a causal effect of perceived prevalence of atheists on distrust in science. Studies 3-4 (the latter preregistered) manipulated the concept of science-atheism associations more generally, revealing the same effects. These effects were mediated by the belief that scientists are anti-religion, not by moral distrust toward atheists or fundamentalist religious beliefs. Hence, Christians' institutional distrust in secularized science may derive largely from a perceived threat to the cultural status of religion.

Green Tea Catechin-Inactivated Viral Vaccine Platform

Traditionally, chemical agents such as formalin (FA) and β-propiolactone (BPL) have long been used for the preparation of inactivated vaccines or toxoids. It has been shown that FA extensively modifies vaccine antigens and thus affects immunogenicity profiles, sometimes compromising the protective efficacy of the vaccines or even exacerbating the disease upon infection. In this study, we show that natural catechins from green tea extracts (GT) can be used as an inactivating agent to prepare inactivated viral vaccines. GT treatment resulted in complete and irreversible inactivation of influenza virus as well as dengue virus. In contrast to FA that reacted extensively with multiple amino acids including lysine, a major anchor residue for epitope binding to MHC molecules, GT catechin epigallocatechin-3-gallate (EGCG) crosslinked primarily with cysteine residues and thus preserved the major epitopes of the influenza hemagglutinin. In a mouse model, vaccination with GT-inactivated influenza virus (GTi virus) elicited higher levels of viral neutralizing antibodies than FA-inactivated virus (FAi virus). The vaccination completely protected the mice from a lethal challenge and restricted the challenge viral replication in the lungs. Of note, the quality of antibody responses of GTi virus was superior to that with FAi virus, in terms of the magnitude of antibody titer, cross-reactivity to hetero-subtypes of influenza viruses, and the avidity to viral antigens. As the first report of using non-toxic natural compounds for the preparation of inactivated viral vaccines, the present results could be translated into a clinically relevant vaccine platform with improved efficacy, safety, productivity, and public acceptance.

Safety and perception: What are the greatest enemies of HPV vaccination programmes?

Vaccines stimulate a person's immune system to produce an adequate reaction against a specific infectious agent; i.e. the person is protected from that disease without having to get it first. As vaccines are administrated to healthy subjects, they are held to the highest standards of safety. Regarding human papillomavirus (HPV) vaccines, at present three prophylactic vaccines are licensed (bivalent HPV 16/18, quadrivalent HPV 6/11/16/18 and the nonovalent HPV 6/11/16/18/31/33/45/52/58 vaccine). Pre- and post-licensure studies (i.e. not yet for nonovalent HPV vaccine) confirm that HPV vaccines are generally safe and well-tolerated, site injections symptoms are the most common adverse events (AEs) reported, and pain is the most frequently referred local symptom. Serious AEs are rare and not associated with severe sequelae, at least no vaccine-related deaths have occurred. Despite these scientific evidences, it is still difficult to explain to the population the importance of a good vaccination programme. There are many determinants for HPV vaccines hesitancy which represent a barrier that must be overcome in order to increase vaccine coverage, including psychological reactions, religious or cultural aspects, and fear of possible AEs (demyelinating diseases, Complex Regional Pain Syndrome - CRPS, or Postural Orthostatic Tachycardia Syndrome - POTS). A weak communication strategy which frequently suffers due to spread of unverified news by media and websites may lead to the failure of a vaccination programme. Such a situation happened in Japan (2013), due to which a great number of women remain vulnerable to HPV-related cancers. In order to resolve the issues around HPV vaccines acceptance, it is necessary to use good communication strategies. Multicomponent and dialogue-based interventions seem to be the most effective, especially if an adequate language is used, customized according to the vaccination programme target.

Global alignment of immunization safety assessment in pregnancy - The GAIA project

Immunization in pregnancy provides a promising contribution to globally reducing neonatal and under-five childhood mortality and morbidity. Thorough assessment of benefits and risks for the primarily healthy pregnant women and their unborn babies is required. The GAIA project was formed in response to the call of the World Health Organization for a globally concerted approach to actively monitor the safety of vaccines and immunization in pregnancy programs. GAIA aims to improve the quality of outcome data from clinical vaccine trials in pregnant women with a specific focus on the needs and requirements for safety monitoring in LMIC. In the first year of the project, a large and functional network of experts was created. The first outputs include a guidance document for clinical trials of immunization in pregnancy, a basic data collection guide, ten case definitions of key obstetric and neonatal health outcomes, an ontology of key terms and a map of pertinent disease codes. The GAIA Network is designed as an open and growing forum for professionals sharing the GAIA vision and aim. Based on the initial achievements, tools and services are developed to support investigators and strengthen immunization in pregnancy programs with specific focus on LMIC.

The clinical development process for a novel preventive vaccine: An overview

Each novel vaccine candidate needs to be evaluated for safety, immunogenicity, and protective efficacy in humans before it is licensed for use. After initial safety evaluation in healthy adults, each vaccine candidate follows a unique development path. This article on clinical development gives an overview on the development path based on the expectations of various guidelines issued by the World Health Organization (WHO), the European Medicines Agency (EMA), and the United States Food and Drug Administration (USFDA). The manuscript describes the objectives, study populations, study designs, study site, and outcome(s) of each phase (Phase I-III) of a clinical trial. Examples from the clinical development of a malaria vaccine candidate, a rotavirus vaccine, and two vaccines approved for human papillomavirus (HPV) have also been discussed. The article also tabulates relevant guidelines, which can be referred to while drafting the development path of a novel vaccine candidate.

Pediatric anaphylactic adverse events following immunization in Victoria, Australia from 2007 to 2013

BACKGROUND

Anaphylaxis is a rare life-threatening adverse event following immunization (AEFI). Variability in presentation can make differentiation between anaphylaxis and other AEFI difficult. This study summarizes pediatric anaphylaxis AEFI reported to an Australian state-based passive surveillance system.

METHODS

All suspected and reported pediatric (<18 years) anaphylaxis AEFI notified to SAEFVIC (Surveillance of Adverse Events Following Vaccination In the Community) Melbourne, Australia, between May 2007 to May 2013 were analyzed. Clinical descriptions of the AEFI, using the internationally recognized Brighton Collaboration case definition (BCCD) and final outcome were documented.

RESULTS

93% (25/27) of AEFI classified as anaphylaxis met BCCD criteria, with 36% (9/25), assessed as the highest level of diagnostic certainty (Level 1). Median age was 4.7 years (range 0.3-16.2); 48% of cases were male. The vaccine antigens administered included: diphtheria, tetanus, acellular pertussis (DTaP) alone or in combination vaccines containing other antigens in 11 of 25 cases (44%); and live attenuated measles mumps rubella (MMR) vaccine for six (five also had other vaccines concomitantly administered). The estimated incidence rate of anaphylaxis for DTaP vaccines was 0.36 cases per 100,000 doses, and 1.25 per 100,000 doses for MMR vaccines. The majority of cases had rapid onset, but in 24% (6/25) of cases, first symptoms of anaphylaxis developed ≥30 min after immunization. In 60% (15/25) of cases, symptoms resolved ≤60 min of presentation. Intramuscular adrenaline was administered in 90% (18/25) of cases. All cases made a full recovery with no sequelae identified.

CONCLUSION

This comprehensive case series of pediatric anaphylaxis as an AEFI identified that diagnostic criteria are useful when applied to a passive vaccine surveillance system when adequate clinical information is available. Anaphylaxis as an AEFI is rare and usually begins within 30 min of vaccination. However, healthcare professionals and vaccinees/parents should be aware that onset of anaphylaxis can be delayed beyond 30 min following immunization and that medical attention should be sought promptly if anaphylaxis is suspected.

Surveillance for adverse events following immunization from 2008 to 2011 in Zhejiang Province, China

This study summarizes passive surveillance data for adverse events following immunization (AEFI) reported to the National AEFI Surveillance System (NASS) in Zhejiang province and describes reporting trends from 2008 to 2011. AEFI reporting rates were calculated using denominator data from the Individual Immunization Information System and the Zhejiang provincial Bureau of Statistics. A total of 6,265 AEFI records were reported; the overall reporting rate was 9.2 per 100,000 doses. There were two peaks of reporting rates, which were associated mainly with the introduction of the pandemic H1N1 influenza virus vaccine (pH1N1) in 2009 and the measles-mumps vaccine (MM) campaign in 2010. The majority of the AEFI described nonserious events. Fifteen deaths were recorded, but only one was possibly related to immunization. The most frequently reported reactions were fever and injection site reaction. Vaccines distributed in Zhejiang province have proven to be generally safe. The data on AEFI surveillance provide a reference point for ongoing reporting of trends and illustrate the value of the NASS database as a surveillance tool for monitoring of AEFI.

Surveillance for adverse events following immunization (AEFI) in Switzerland--1991-2001

In Switzerland, reporting of adverse events following immunization (AEFI) has been mandatory by law since 1988. The goal of this study was a detailed analysis of reported AEFI received by the Swiss Federal Office of Public Health between 1991 and 2001. Overall, 1013 AEFI were reported which translates to 2.7 reports per 100,000 vaccine doses distributed during the study period. Most AEFI were classified as general systemic reactions (47%), followed by local (26%), neurological (16%) and allergic reactions (13%). The majority of all reported AEFI (N=513; 51%) had occurred in individuals 16 years and older. Causal relationship between immunization and AEFI was probable in 91 (10%) of 909 assessable reports and very likely or certain in 194 (21%), the majority of which (88%) were local reactions. Vaccines distributed in Switzerland have proven to be generally safe. Limitations of the passive surveillance system, however, warrant improvements in the future.

Perceptions of vaccine safety in a global context

Given the serious consequences of low vaccine coverage, concerns and misconceptions need to be taken seriously and responded to appropriately to sustain accomplishments of immunization programmes. For parental decisions related to childhood vaccinations, it seems reasonable to assume that the cultural context of the immunization programme is of importance. This article is a short review of some recent studies of parental decision-making on vaccination in developed countries Kazaktstan, Uzbekistan and Northern Nigeria. Furthermore, an attempt is made to relate the findings in these studies to theoretical models of parental decision-making.

CONCLUSION

For the implementation of immunization programmes, it is important to develop an in-depth understanding of mechanisms underlying decisions to accept or reject the vaccination of a child. Theoretical models may aid in the understanding of these mechanisms.

Human papillomavirus immunisation of adolescent girls and anticipated reporting of immune-mediated adverse events

Determining incidence rates of potential adverse events before and after an immunisation programme is initiated, provides a useful framework for the evaluation of vaccine safety concerns. Human papillomavirus vaccination (HPV) of adolescent girls has recently been introduced in Denmark. Using a nationwide hospitalisation registry we estimated incidence rates of immune-mediated disorders before HPV vaccination in a cohort of 418,289 Danish girls aged 12-15 years. We further estimated the expected number of cases of immune-mediated disorders occurring in temporal relationship to a hypothetical HPV vaccination schedule purely by chance. Our results and analytical approach provides a framework for the evaluation of adverse event reports following immunisation of adolescent girls.

[Prevention of infectious diseases in industrialized countries]

Präventionsmaßnahmen zur Verhinderung von Infektionskrankheiten können individuelle, zielgruppenspezifische oder bevölkerungsbezogene Ansätze verfolgen. Schutzimpfungen gehören zu den effektivsten und kostengünstigsten Präventionsmaßnahmen im medizinischen Bereich und schützen sowohl das Individuum als auch die Bevölkerung vor Krankheitsausbrüchen. Das Ziel von Impfprogrammen kann die Verminderung der Krankheitslast sowie die Kontrolle, Elimination oder Eradikation eines Erregers sein. Einige impfpräventable Erkrankungen sind in den industrialisierten Ländern bereits weitestgehend eliminiert. Zur Reduktion der Morbidität und Letalität in Folge von Influenza- und Pneumokokkeninfektionen ist eine konsequente Umsetzung der Impfempfehlungen Voraussetzung. Allerdings findet sich in der erwachsenen Bevölkerung oft eine unzureichende Durchimpfung, hier sind insbesondere internistisch tätige Ärzte gefordert.