Challenges and controversies in immunization safety

Is Vaccine Hesitancy Affected by Distrust in the Healthcare System? A Study in Turkish Population

The aim of this study is to examine the effect of the perception of distrust in the healthcare system on vaccine hesitancy and to determine the association between the sociodemographic characters of the participants and their perception of distrust and their vaccine hesitancy. The population consisted of individuals who were 20 years old and above and were residing in Turkey. A total of 986 people participated in the study. The data were collected through a questionnaire that was prepared on Google Forms. As a result of the regression analysis, distrust in the healthcare system explained 20.7% of total variance in vaccine hesitancy and an increase in the perception of distrust in the healthcare system statistically increased the vaccine hesitancy. In the study, it was also determined that the participants' perceptions of distrust in the healthcare system caused statistically significant differences based on the variables of marital status, employment status, alcohol consumption, age, education level and income level. It was revealed that the participants' perceptions of vaccine hesitancy caused a statistically significant difference only based on age and the frequency of applying to the health institution.

Guillain-Barre Syndrome Following SARS-CoV-2 Vaccination: A Case Report

After more than a year of Coronavirus disease 2019 pandemic, in 2021 Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccination have been made possible and vaccine was distributed globally. Since then, there have been reports of symptoms following SARS-CoV-2 vaccination, including neurological symptoms of ascending paralysis known as Guillain-Barre syndrome. In this report, we describe the first case of Guillain-Barre syndrome following vaccination in Indonesia. Symptoms of ascending paralysis were of late onset after the first dose, however, were full blown after receiving the second dose followed by left-sided facial paralysis.

Taking a Shot at Immunization Adherence Group Visits for Vaccine-Averse Parents

Introduction

Decreased vaccination rates in children have played a role in the deaths of several children in the United States over the last decade. Interventions to date have been ineffective at changing vaccination patterns. No studies have evaluated a conciliatory patient-centered approach where parent concerns were acknowledged and addressed in a group setting.

Methods

Vaccine-averse parents with incompletely vaccinated children were recruited from a family medicine practice. These parents attended three group visit sessions centered on vaccine safety and efficacy. Pre and post surveys were given at each session. The children's vaccination records were examined in the year prior and the year following the groups. One year after the group visits, parents were interviewed about their attitudes toward vaccination.

Results

There were no significant attitude changes in parents attending the group visits. In the year following the visits, the percentage of recommended vaccines that children had received did not increase. Interviews with parents revealed a broad range of concerns about vaccines and a widespread desire for a longer-term study designed to address these concerns.

Conclusions

Surveys and vaccination records revealed no significant change in attitudes or behavior after three group visit sessions, consistent with other research on interventions with vaccine-averse parents. The phone interviews demonstrated a desire for further research into long-term effects of vaccines, with most parents stating that they would consider changing their beliefs if the research was free from commercial bias, addressed their concerns, and was extended out over a long period of time.

Parents' and adolescents' willingness to be vaccinated against serogroup B meningococcal disease during a mass vaccination in Saguenay-Lac-St-Jean (Quebec)

A mass vaccination campaign with the 4CMenB vaccine (Bexsero®; Novartis Pharmaceutical Canada Inc) was launched in a serogroup B endemic area in Quebec. A telephone survey was conducted to assess parental and adolescent opinions about the acceptability of the vaccine. Intent to receive the vaccine or vaccine receipt was reported by the majority of parents (93%) and adolescents (75%). Meningitis was perceived as being a dangerous disease by the majority of parents and adolescents. The majority of respondents also considered the 4CMenB vaccine to be safe and effective. The main reason for positive vaccination intention or behaviour was self-protection, while a negative attitude toward vaccination in general was the main reason mentioned by parents who did not intend to have their child vaccinated. Adolescents mainly reported lack of interest, time or information, and low perceived susceptibility and disease severity as the main reasons for not intending to be vaccinated or not being vaccinated.

Compliance with regimens of existing vaccines in Orumba North local government area of Anambra state, Nigeria

The factors associated with third dose of diphtheria, pertussis and tetanus (DPT3) uptake, a true indicator of compliance with required regimen of vaccines, in Anambra state, Nigeria, were investigated in a cross-sectional survey of 600 mothers (15-49). Being an older mother showed a positive association with compliance. Compliance was more among those who used the government health facilities for their health needs (χ(2 )= 12.286, p < .001). Satisfactory experiences with health service influenced compliance (χ(2 )= 8.542, p = .002). Those with good perception (30.1%) complied more (χ(2 )= 42.572, p < .001). Those who were aware that immunization protects the children against vaccine preventable diseases complied more (χ(2 )= 8.735, p = .002). In conclusion, the action-hesitancy model strengthens the Health Belief Model in explaining parents' attitude to childhood immunization, as experience and perception of the health service influenced uptake more. Health education and campaigns should be directed at factors that would encourage mothers to adopt required behaviours.

Compliance With Regimens of Existing Vaccines in Orumba North Local Government Area of Anambra State, Nigeria

The factors associated with third dose of diphtheria, pertussis and tetanus (DPT3) uptake, a true indicator of compliance with required regimen of vaccines, in Anambra state, Nigeria, were investigated in a cross-sectional survey of 600 mothers (15–49). Being an older mother showed a positive association with compliance. Compliance was more among those who used the government health facilities for their health needs (χ2 = 12.286, p < .001). Satisfactory experiences with health service influenced compliance (χ2 = 8.542, p = .002). Those with good perception (30.1%) complied more (χ2 = 42.572, p < .001). Those who were aware that immunization protects the children against vaccine preventable diseases complied more (χ2 = 8.735, p = .002). In conclusion, the action-hesitancy model strengthens the Health Belief Model in explaining parents’ attitude to childhood immunization, as experience and perception of the health service influenced uptake more. Health education and campaigns should be directed at factors that would encourage mothers to adopt required behaviours.

A systematic review of interventions for reducing parental vaccine refusal and vaccine hesitancy

Unvaccinated individuals pose a public health threat to communities. Research has identified many factors associated with parental vaccine refusal and hesitancy toward childhood and adolescent immunizations. However, data on the effectiveness of interventions to address parental refusal are limited. We conducted a systematic review of four online databases to identify interventional studies. We used criteria recommended by the WHO's Strategic Advisory Group of Experts on immunization (SAGE) for the quality assessment of studies. Intervention categories and outcomes were evaluated for each body of evidence and confidence in overall estimates of effect was determined. There is limited evidence to guide implementation of effective strategies to deal with the emerging threat of parental vaccine refusal. There is a need for appropriately designed, executed and evaluated intervention studies to address this gap in knowledge.

Attitudes and beliefs of parents concerned about vaccines: impact of timing of immunization information

OBJECTIVES

To determine if giving vaccine-information materials before the 2-month vaccination visit to mothers with concerns about vaccine safety positively changed their attitudes and beliefs about vaccine safety.

METHODS

Mothers who indicated concerns about infant vaccinations were recruited from 2 separate sites in Tennessee and California and were given vaccine information at 1 of 3 times: during a prenatal visit; a 1-week postpartum well-child visit; or a 2-month vaccination visit. A separate group of concerned mothers was assigned to be followed longitudinally at all 3 time points and was analyzed separately. The mothers reviewed a new vaccine-information pamphlet and Vaccine Information Statements (VIS) from the Centers for Disease Control and Prevention. Attitudes and beliefs about immunization were assessed both before and after the review of materials with written surveys.

RESULTS

A total of 272 mothers with immunization concerns participated in the study. After review of the materials, mothers in all groups were significantly more likely to respond positively to questions and statements supporting the safety and importance of vaccines. Mothers who received this information at earlier visits were not significantly more likely to respond positively than mothers who received the information at the child's 2-month vaccination visit; however, participating mothers did indicate a preference for receiving vaccine information before the first vaccination visit.

CONCLUSIONS

Distribution of the vaccine-information pamphlet and Vaccine Information Statements significantly improved attitudes about vaccination regardless of at what visit they were provided. Allowing adequate time to review vaccine information, even if done at the vaccination visit, may benefit concerned mothers.

Vaccines and Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is the leading cause of acute flaccid paralysis in developed countries and is characterized by various degrees of weakness, sensory abnormalities and autonomic dysfunction. Although the underlying aetiology and pathophysiology of GBS are not completely understood, it is broadly believed that immune stimulation plays a role in its pathogenesis. Thus, since vaccines have an effect on the immune system it is biologically plausible that immunizations may be associated with subsequent GBS. The objective of this article is to review the current body of evidence that either supports or does not support a causal, rather than just temporal, association between various vaccines and GBS, and to provide an evidence-based review of this issue. The scope of the article includes published reports that, regardless of method of case ascertainment, appeared in peer-reviewed literature between 1950 and 2008. Our review indicates that, with rare exceptions, associations between vaccines and GBS have been only temporal. There is little evidence to support a causal association with most vaccines. The evidence for a causal association is strongest for the swine influenza vaccine that was used in 1976-77. Studies of influenza vaccines used in subsequent years, however, have found small or no increased risk of GBS. Older formulations of rabies vaccine cultured in mammalian brain tissues have been found to have an increased risk of GBS, but newer formulations of rabies vaccine, derived from chick embryo cells, do not appear to be associated with GBS at a greater than expected rate. In an earlier review, the Institute of Medicine concluded that the evidence favoured a causal association between oral polio vaccine and tetanus toxoid-containing vaccines and GBS. However, recent evidence from large epidemiological studies and mass immunization campaigns in different countries found no correlation between oral polio vaccine or tetanus toxoid-containing vaccines and GBS. Spontaneous reports to the US Vaccine Adverse Events Reporting System shortly after the introduction of quadrivalent conjugated meningococcal vaccine (MCV4) raised concerns of a possible association with GBS. Comparisons with expected rates of GBS, however, were inconclusive for an increased risk, and lack of controlled epidemiological studies makes it difficult to draw conclusions about a causal association. For other vaccines, available data are based on isolated case reports or very small clusters temporally related to immunizations, and no conclusion about causality can be drawn. There are certain circumstances in which immunizing individuals, particularly those with a prior history of GBS, may require caution. However, the benefit of vaccines in preventing disease and decreasing morbidity and mortality, particularly for influenza, needs to be weighed against the potential risk of GBS.

Maximizing the effectiveness of a pediatric vaccine formulary while prohibiting extraimmunization

The growing-complexity of the United States Recommended Childhood Immunization Schedule has resulted in as many as five required injections during a single well-baby office visit. To reduce this number, vaccine manufacturers have developed combination vaccines that immunize against several diseases in a single injection. At the same time, a growing number of parents are challenging the safety and effectiveness of vaccinating children. They are also particularly concerned about the use of combination vaccines, since they believe that injecting a child with multiple antigens simultaneously may overwhelm a child's immune system. Moreover, combination vaccines make it more likely that extraimmunization (i.e., administering more than the required amount of vaccine antigens) occurs, resulting in greater concerns by parents and vaccine wastage costs borne by an already strained healthcare system. This paper formulates an integer programming model that solves for the maximum number of vaccines that can be administered without any extraimmunization. An exact dynamic programming algorithm and a randomized heuristic for the integer programming model is formulated and the heuristic is shown to be a randomized xi-approximation algorithm. Computational results are reported on three sets of test problems, based on existing and future childhood immunization schedules, to demonstrate their computational effectiveness and limitations. Given that future childhood immunization schedules may need to be solved for each child, on a case-by-case basis, the results reported here may provide a practical and valuable tool for the public health community.

Survey of vaccine distribution and delivery issues in the USA: from pediatrics to pandemics

Vaccine distribution and delivery has become an issue of significant interest, given the threat of a pandemic influenza outbreak and the resulting need for coordinated efforts to distribute and deliver pandemic influenza vaccines into the hands of healthcare workers responsible for administering them. This review provides an overview of the issues that are most relevant to vaccine distribution and delivery, including routine pediatric immunization, combination vaccines, vaccine shortages and stockpiling, seasonal influenza vaccines and, of most current interest, a discussion on pandemic influenza outbreak issues and a list of future distribution and delivery challenges that may be faced during such an event.

Addressing parents' concerns about childhood immunizations: a tutorial for primary care providers

BACKGROUND

Despite the dangers of vaccine-preventable infections and efforts by health care professionals to promote immunization, parents' resistance to routine childhood immunizations continues to grow. This phenomenon can give rise to frustration among health care providers, as well as create barriers in providing medical care to children in need. In response, we developed a CD-ROM-based tutorial that (1) explains the nature and origins of parents' concerns, (2) addresses clinical implications of resistance to immunization, (3) explores ethical and professional obligations that physicians have toward children and their parents, and (4) discusses how physicians can effectively address parents' concerns.

OBJECTIVE

Our goals were to evaluate the tutorial's effectiveness in improving physicians' (1) general knowledge about parents' resistance to childhood immunizations, (2) knowledge of adverse effects of immunization, and (3) attitudes toward parents' resistance to childhood immunization.

DESIGN/METHODS

After pretesting, expert review, and revision, the 45-minute Penn State Immunization Project tutorial was pilot tested with pediatric and family medicine residents at 7 training programs in 4 states (Pennsylvania, New York, Maryland, and Iowa). Knowledge and attitudes were assessed by using a 26-item pretest/posttest, the results of which were then analyzed by using standard statistical methods.

RESULTS

A total of 122 residents completed the pretest/posttest. Statistically and clinically significant improvements were seen in residents' general knowledge, knowledge of adverse events, and all 5 attitudinal measures regarding childhood immunizations.

CONCLUSIONS

The tutorial Addressing Parents Concerns About Childhood Immunizations: A Tutorial for Primary Care Providers is effective in improving resident physicians' general knowledge, knowledge of adverse events, and attitudes. As such, this tutorial has the potential to enhance communication between parents and primary care providers and, more generally, improve clinicians' response to the growing resistance toward routine childhood immunizations.

Addressing the emergence of pediatric vaccination concerns: recommendations from a Canadian policy analysis

Ever since the advent of pediatric vaccination, individuals have expressed concerns about both its risks and benefits. These concerns have once again resurfaced among some segments of the population and could potentially undermine national vaccination programs. The views of the public, however, must be considered and respected in the formulation of vaccination policy. We have conducted an analysis of the pediatric vaccination "debate" in the Canadian context. We believe that there is common ground between those who support pediatric vaccination and those who are concerned about these programs. Based on our findings, we believe that the goal of public health authorities should be to maintain trust in vaccines by continuing to meet certain reciprocal responsibilities. To do so, we recommend the following: 1) increased investment in adverse event reporting systems; 2) request for proposals for consideration of a no-fault compensation program; 3) developing pre-emptive strategies to deal with potential vaccine risks; 4) further examination of mechanisms to improve communication between physicians and parents concerned about vaccination. All of these approaches would require additional investment in pediatric vaccination. However, such an investment is easy to justify given the benefits offered by pediatric vaccination and the ramifications of failing to maintain confidence in vaccination programs or missing a vaccine-related adverse event.

Actions and Beliefs Related to Hepatitis B and Influenza Immunization Among Registered Nurses in Texas

Studies indicate that roughly half of health care workers are not immunized against hepatitis B and influenza. Findings from a survey of 1,000 registered nurses (RNs) conducted to analyze their beliefs and actions related to immunization recommendations are reported. Only 8% of the responding RNs chose not to receive vaccination against hepatitis B. The primary reasons that nurses declined hepatitis B vaccination were because they were not working in nursing or did not believe they were at risk of exposure. Similarly, 86% of the RNs reported they had ever received a flu shot, and 69% reported of being immunized during 2 of the previous 4 years. Rationale for receiving immunization included belief in its effectiveness, belief that they were at risk of exposure, and that it was provided free of charge. Reasons for declining included concerns about side effects, lack of concern about getting the illness, and doubts about effectiveness. The nurses who responded to the survey appear to value immunizations and generally adhere to immunization recommendations. Further study needs to be conducted on related issues, including follow-up for assessment of long-term protection of hepatitis B immunization and adherence to guidelines for postexposure prophylaxis. Ongoing monitoring and further study of serious complications of hepatitis B immunizations are also needed.

Effect of infant immunisation on childhood mortality in rural Bangladesh: analysis of health and demographic surveillance data

BACKGROUND

In developing countries, immunisation programmes must compete with other strategies to improve public health and quality of life. Studies of long-term effects of immunisation programmes are rare. We assessed associations between vaccinations and mortality over 15 years after the introduction of routine infant immunisation programmes in Matlab, Bangladesh.

METHODS

We analysed data recorded in a comprehensive health and demographic surveillance system from 1986 to 2001. We did univariate analyses and assessed vaccinations as independent factors with other variables in Cox models with time dependent covariates.

FINDINGS

Diphtheria-tetanus-pertussis (DTP) and oral polio vaccination were independently associated with decreased risk of death before age 9 months, as were amount of maternal education, maternal age, and birth order of the child. DTP vaccination was associated with increased survival (hazard ratio=0.76, 95% CI 0.67-0.88; p=0.001) in a model evaluating mortality between 6 weeks and 9 months of age. Measles vaccination was also associated with increased survival when data after late immunisation with DTP and Bacille Calmette-Guérin (BCG) were excluded. BCG vaccination was associated with reduced survival; however, children vaccinated with BCG during the first 6 months of life had significantly lower risk of death than those vaccinated later (hazard ratio=0.59; 95% CI 0.47-0.73; p=0.0001).

INTERPRETATION

By contrast with previous findings, we noted substantially reduced mortality among children who received DTP vaccine. This effect could be due to actual protection against pertussis disease and secondary illnesses or to a non-specific benefit, although we cannot rule out epidemiological artifact. Our findings show the value of population-based health surveillance systems.

The use of vaccines in pregnancy

Adult immunization rates in the United States lag behind pediatric immunization rates. Healthcare providers in all settings should discuss immunization with their patients. There are concerns regarding the use of vaccine in women who are pregnant or breastfeeding. This article reviews selected vaccines and the use of vaccines in women who are pregnant or breastfeeding. Basic principles of vaccine administration are discussed as well as standards for immunization practice. Concerns regarding vaccine safety in any population are reviewed.

The National Immunization Information Hotline

The National Immunization Information Hotline (NIIH) has been providing information regarding immunizations to the public and to health care professionals since March 1997. We describe the operations of the NIIH, its experience over the first two and a half years of operation and lessons learned for other immunization hotlines. From 1998-2000, the hotline answered 246,859 calls. Calls concerning immunization information requests totaled 175,367; data about the calls were collected from 35,102. Approximately a third of the 35,102 calls were from health care providers. Of the remaining calls from the public, the greatest number of calls concerned childhood immunizations. Immunization schedule queries from the public increased 323.0% from 1998 to 2000. While the major goal of the NIIH is to provide accurate and reliable information to the public and to health care providers, data from the hotline can be used to monitor changes over time in calls concerning inquiries about the immunization schedule in addition to other variables of interest.

Parental perceptions surrounding risks and benefits of immunization

In recent years, parental concerns about vaccine safety have increased as the threat of disease has decreased. A national survey showed that, in general, parents agree that vaccines benefit their children and that their children may be at risk for contracting a disease if unvaccinated. When asked about understanding the benefits and risks of vaccines, most parents (57%) found numbers and statistics most helpful. A substantial minority (17%) of parents were somewhat or not confident in vaccine safety. Parents less confident in vaccine safety agreed less with the statement that they usually followed the advice of their child's doctor. Incomes and education levels affected responses. This positive relationship between confidence in vaccine safety and reliance on doctors for advice may indicate the need for healthcare providers to identify opportunities to (1) solicit questions about vaccine safety, (2) address vaccine safety-related questions in a way meaningful to parents, and (3) strengthen doctor-patient relationships. A parent communication tool is proposed.

The overall safety profile of currently available vaccines directed against infectious diseases

The vaccines currently used worldwide for the prevention of infectious diseases are quite safe in comparison to most pharmaceutical and biological agents. Vaccine components may contribute to inflammatory, allergic or anaphylactic reactions. Most adverse events are transient and well-tolerated. Transient severe adverse reactions occur at rates of one in one thousand vaccinations; permanent severe adverse reactions occur on the order of one in one million. The most common of the severe adverse reactions are syncope and allergic reactions. Providers can take steps to prevent or ameliorate these reactions by pursuing both prelicensure testing (albeit limited) and postlicensure testing and monitoring. Systems that enhance the detection of safety concerns include national passive and active surveillance as well as regional vaccine registries and provider-based patient education. Since vaccines are used in universal programmes, their safety is paramount to their continued acceptance. Healthcare managers, including administrators of hospitals, clinics, practice groups, health maintenance organisations (HMOs) and managed care plans, can and should support providers in minimising adverse events associated with vaccines by supporting postvaccination observation policies, postlicensure testing and surveillance, vaccine registries and patient education systems.

Childhood autism: a circuit syndrome?

BACKGROUND

Autism is a disorder that can lead to life-long disability. Currently, the etiology of autism is unknown, and although there are treatments for some of the behavioral abnormalities, there is no cure.

REVIEW SUMMARY

While this article will review the clinical, anatomic, and pathologic features seen in autism, the primary focus will be to present a new and provocative unifying theory regarding the underlying mechanisms causing this disorder. Current research advances, some controversial, will be discussed, and a novel definition of autism as a "circuit syndrome" will be presented. The work elaborated here will tie many of the disparate findings together, based on the idea that autism arises from abnormalities of the cerebellolimbic circuitry. Some of the more alternative theories of autism, such as mercury toxicity, linkage to the measles, mumps, and rubella vaccine, and the use of secretin will be discussed. Finally, pharmacologic treatment options will be reviewed.

CONCLUSIONS

Autism is not single disorder but represents dysfunction of the cerebellolimbic circuitry that can arise from many different etiologies.

The challenge of vaccine safety

Vaccines always will involve some risk, and risk always involves some public concern. Although the benefits of routine vaccination greatly outweigh any adverse effects, our consumer society seeks to eliminate all risk. The balance of risk and benefit appears to falter by the very success of preventing disease: in the immediate absence of the disease, the resolve to vaccinate waivers. We cannot expect the public to think in terms of the decision analyst and carefully weigh probability, risk, and benefit in a numerical fashion. In fact, the public's approach toward vaccination is varied and unscientific. Recognizing these challenges, we propose a program of continued vigilance by increasing our scientific base and methodology, improving vaccine safety communication through research and resources, maintaining a tolerance of conscientious objection as a safety valve for mandated routine vaccination in civilians, and calling for more research funding for the development of new vaccines.

Challenges to vaccine safety

The end of the 20th century saw the realization of a goal that was previously only dreamed about: the near elimination of many deadly infectious diseases through universal vaccination. As one disease after another has been driven from memory, it is vaccination programs themselves that have come to occupy the public's mind. With increased scrutiny comes the promise that vaccines will become even safer, but there is also the threat that ill-founded concerns will result in reduced immunization rates, and diseases will resurge. This article reviews scientific data relating to current vaccine safety concerns.