Vaccine-Preventable Diseases Requiring Hospitalization

Barriers to vaccination in immunocompromised children: A needs assessment in children with childhood-onset SLE and inflammatory bowel disease

Background

Vaccination of immunocompromised children (ICC) remains suboptimal.

Methods

Needs assessment surveys were administered to patients and caregivers during routine ambulatory visits to the rheumatology and gastroenterology clinics at Nationwide Children's Hospital (NCH) from January 1 through August 31, 2018, and to community primary care physicians (PCPs) at their monthly meeting and electronically.

Results

Completed surveys were received for 57 patients (31 with childhood-onset systemic lupus erythematosus (c-SLE) and 26 with inflammatory bowel disease (IBD)) and 30 PCPs. Of the patient cohort, 93% (n = 53) felt their PCP was well informed about vaccines and 84% (n = 47) received vaccinations from either their PCP or local health department. Two patient surveys noted concerns of vaccine safety. Among the 30 responses completed by PCPs 50% (n = 15) preferred to provide all vaccines themselves, however, only 40% (n = 12) of PCPs felt "very confident" when providing vaccines to ICC. Further, 83% (n = 25) did not stock the 23-valent pneumococcal vaccine and only 27% (n = 8) routinely recommended vaccination of household contacts.

Conclusions

Our study found a discordance between parent and PCP comfort in vaccinating ICC, highlighting an important barrier to vaccination in this patient population. In our cohort of patients, vaccine hesitancy was not a barrier to vaccination.

Admissions due to vaccine preventable diseases in a large paediatric intensive care unit in Greece over a 10-year period

AIM

Childhood immunisation is an important preventive measure. However, care givers may delay routine immunisations or seek exemptions from state vaccine mandates. Vaccine refusal creates barriers on vaccine coverage and leads to morbidity and mortality.

METHODS

Our study reviews morbidity and mortality from vaccine preventable diseases (VPDs) in a large paediatric intensive care unit in Greece over a 10-year period.

RESULTS

During the study period, 73 cases of VPDs were recorded, corresponding to 3.5% of total paediatric intensive care unit admissions. Influenza was the most prevalent VPD, followed by pneumococcal disease, measles, pertussis and meningococcal disease. Most patients (83.3%) were unvaccinated for the admission's VPD. Outcome was unfavourable for 31.9% of the patients (17 children died, 6 developed chronic impairment).

CONCLUSION

Absent or incomplete vaccination may result in serious morbidity and mortality from preventable diseases. Strengthening vaccination strategies are needed to improve individual protection as well as herd immunity.

Vaccination patterns of the northeast Ohio Amish revisited

OBJECTIVES

The Holmes County Amish have low vaccination rates, an increasingly diverse population, and have an increased incidence of certain inherited diseases. The objectives were to evaluate; the rate and influences of vaccine hesitancy compared to a decade ago, vaccination patterns between Amish affiliations, vaccine practices of Amish special needs children, and the Amish's acceptance of a COVID-19 vaccine.

STUDY DESIGN

In April of 2020, a survey assessing vaccination patterns and beliefs were mailed to 1000 Amish families, including ultra-conservative Amish sects and special needs families.

RESULTS

The response rate was 39%. Among 391 respondents, 59% did not vaccinate their children, compared to only 14% that refused all vaccinations reported by Wenger et al in the same community only a decade ago. The ultra-conservative Amish rejected vaccines more often. Amish special needs children were more likely to receive vaccines than healthy Amish children. 75% responded they would reject a COVID-19 vaccine. Fear of adverse effects was the most common reason to reject vaccines. Families that accepted vaccines were more likely to cite a healthcare worker as the primary influence to vaccinate. Wives were more likely to cite their spouse as the primary influence to vaccinate. Families that rejected vaccines were more likely to state their bishop was the most influential person on vaccination.

CONCLUSION

The Holmes County Amish have decreasing vaccine acceptance. Efforts to improve vaccination will require a targeted focus on the primary influences and beliefs of sub-populations within the Amish. Physician advocacy, peer mentorship, father-directed education, and close partnership with Church leadership will be needed to limit vaccine-preventable disease. The Amish may be at risk for low uptake of a COVID-19 vaccine.

Pediatric Tetanus in Central Pennsylvania

Approximately 20% of the nationally reported tetanus infections in children aged 0 to 14 years that occurred in the United States between 2005 and 2015 were treated at Penn State Children's Hospital. With an electronic medical record search, we identified 5 cases of pediatric tetanus; 100% of these cases occurred in unimmunized children. Their median length of stay was 10 days, and the costs were significant.

Pertussis outbreak in an Amish Community: Kent County, Delaware, 2018

The Amish lead a very simplistic lifestyle free of modern conveniences. They have unique perceptions and beliefs regarding health and illness and generally do not adhere to conventional preventive measures such as immunizations, which can result in un- or under-immunized populations. Populations with low vaccination coverage are at greater risk of outbreaks compared to vaccinated populations as a result of low herd immunity. Over the past two decades, the Delaware Division of Public Health (DPH) has recorded three distinct outbreaks of pertussis in Delaware's Amish community. The third, and most recent, outbreak was detected in May 2018. DPH conducted an outbreak investigation in the Amish community to identify cases, estimate the burden of disease in the community, and implement control measures including vaccination, treatment, and post-exposure prophylaxis. Through the conduct of active surveillance activities, DPH interviewed 134 families and identified 181 confirmed and probable cases of pertussis. The majority of pertussis cases (77%) occurred among children ≤10 years of age, of which 87% were unvaccinated. DPH engaged the Amish community in meetings, distributed educational materials, and provided medication and vaccines in the community to encourage prevention and implement control measures. DPH officially closed the outbreak investigation on December 20, 2018 following three full incubation periods (63 days) without any new pertussis cases identified in the community.

Characterizing the impact of spatial clustering of susceptibility for measles elimination

Measles elimination efforts are primarily focused on achieving and maintaining national vaccination coverage goals, based on estimates of the critical vaccination threshold (Vc): the proportion of the population that must be immune to prevent sustained epidemics. Traditionally, Vc estimates assume evenly mixing populations, an invalid assumption. If susceptible individuals preferentially contact one another, communities may remain vulnerable to epidemics even when vaccination coverage targets are met at the national level. Here we present a simple method to estimate Vc and the effective reproductive number, R, while accounting for spatial clustering of susceptibility. For measles, assuming R0 = 15 and 95% population immunity, adjustment for high clustering of susceptibility increases R from 0.75 to 1.29, Vc from 93% to 96%, and outbreak probability after a single introduction from <1% to 23%. The impact of clustering remains minimal until vaccination coverage nears elimination levels. We illustrate our approach using Demographic and Health Survey data from Tanzania and show how non-vaccination clustering potentially contributed to continued endemic transmission of measles virus during the last two decades. Our approach demonstrates why high national vaccination coverage sometimes fails to achieve measles elimination, and that a shift from national to subnational focus is needed as countries approach elimination.