National rates and disparities in childhood vaccination and vaccine-preventable disease during the COVID-19 pandemic: English sentinel network retrospective database study

Impact of COVID-19 on vaccine confidence and uptake: A systematic literature review

During the coronavirus disease 2019 (COVID-19) pandemic, scheduled vaccinations were postponed, mass vaccination programmes were suspended and opportunities for healthcare workers to administer vaccines ad hoc decreased. The aims of this systematic literature review were to determine the impact of the COVID-19 pandemic on vaccine confidence, intent and uptake in preexisting routine childhood or adult vaccination programmes, and to identify factors associated with changes in acceptance, intent and uptake of preexisting vaccines. Medline and Embase were searched for studies in Australia, Brazil, Canada, China, Japan, the USA, and European countries, published between 1 January 2021 and 4 August 2022. A complementary gray literature search was conducted between 11 and 13 October 2022, and supplemented with additional gray research in October 2023. In total, 54 citations were included in the review. Study design and geography were heterogeneous. The number of adults who received or intended to receive an influenza or pneumococcal vaccine was higher during the pandemic than in previous seasons (n = 28 studies). In addition, increased acceptance of adult vaccinations was observed during 2020-21 compared with 2019-20 (n = 12 studies). The rates of childhood vaccinations decreased during the COVID-19 pandemic across several countries (n = 11 studies). Factors associated with changes in intention to receive a vaccination, or uptake of influenza vaccine, included previous vaccination, older age, higher perceived risk of contracting COVID-19, anxiety regarding the pandemic and fear of contracting COVID-19. Acceptance and uptake of influenza and pneumococcal vaccines generally increased after onset of the COVID-19 pandemic.

Worth a Shot: Experience and Lessons From an Unsuccessful Pediatric Immunization Quality Improvement Effort in a Large Health System During the COVID-19 Pandemic

INTRODUCTION

During the coronavirus disease of 2019 (COVID-19) pandemic, routine childhood immunization rates dropped dramatically across the world, and the Military Health System (MHS) was no exception. In the MHS, which is a large, universally covered, low-to-no-cost health system, the immunization rates with the measles, mumps, and rubella (MMR) vaccine remain below the rate necessary to prevent community transmission of measles. We aimed to improve childhood immunization rates in the MHS with an expansive quality improvement project.

MATERIALS AND METHODS

Measles, mumps, and rubella immunization rates served as proxy outcome measures for routine immunization rates tracked by the Center for Disease Control multi-immunization combination measures. The tracked measure was the percentage of 16- to 18-month olds and 6-year olds who had received MMR #1 and MMR #2, respectively. Various countermeasures were implemented throughout the study period, and standard quality improvement analyses informed the effect of countermeasures.

RESULTS

By January 2023, the percentage of 16- to 18-month olds and 6-year olds who had received MMR #1 and MMR #2 was 85% and 91%, respectively, with no positive shift in immunization rates despite various countermeasures introduced during the study period. For reference, the MMR immunization rates of commercial health maintenance organization and commercial preferred provider organization for 24-month-old populations were 92% and 90.3%, respectively. On chart review, the most common cause for under-immunization (55%) was vaccine abandonment. MMR #1 rates rose to 92% in 24-month olds.

CONCLUSIONS

Measles, mumps, and rubella immunization rates within the MHS remained below commercial health system rates and below public health standards required for herd immunity despite various countermeasures throughout the COVID-19 pandemic. Immunization rates increased with age, suggesting that children within the MHS eventually catch up despite potential barriers.

'Why did nobody ask us?': A mixed-methods co-produced study in the United Kingdom exploring why some children are unvaccinated or vaccinated late

OBJECTIVE

Childhood vaccine uptake in the United Kingdom (UK) is sub-optimal leading to outbreaks of preventable diseases. We aimed to explore UK parents' perspectives on why some children are unvaccinated or vaccinated late.

METHODS

We undertook a mixed-methods, co-production study involving a survey using a questionnaire followed by focus groups. We partnered with The Mosaic Community Trust (Mosaic) who are based in a more deprived, ethnically diverse, low vaccine uptake area of London. Targeted recruitment to complete the questionnaire (either on paper or online) was done through Mosaic, community networks and social media promotion. We collected demographic data alongside parents' views on routine childhood vaccination, their vaccine decisions, and experiences of accessing childhood vaccine appointments We report descriptive findings from the questionnaire and thematic analysis of free-text questionnaire answers and focus groups guided by the COM-B model of Capability, Opportunity, and Motivation.

RESULTS

Between June-October 2022, 518 parents were surveyed of whom 25% (n = 130), were from ethnic minorities (13%, n = 68-unknown ethnicity). In 2023 we held four focus groups with 22 parents (10 from ethnic minorities). Only 15% (n = 78) parents had delayed or refused a vaccine for their child. A quarter of parents felt they had not been given enough information nor an opportunity to ask questions before their children's vaccinations. Inconsistent reminders and difficulties booking or attending appointments impacted vaccine uptake with negative experiences influencing future vaccine decisions. Parents had mixed views on vaccinations being given in different locations and wanted trusted health professionals to vaccinate their children.

CONCLUSION

To reverse declining vaccine uptake and prevent future outbreaks it needs to be easier for UK parents to speak to health professionals to answer their childhood vaccine questions, alongside simplified booking systems and easier access to routine childhood vaccine appointments.

Vaccine Coverage at 36 Months and 7 Years by Parental Birth Country, Washington State

BACKGROUND AND OBJECTIVES

Ensuring equitable vaccination access for immigrant communities is critical for guiding efforts to redress health disparities, but vaccine coverage data are limited. We evaluated childhood vaccination coverage by parental birth country (PBC) through the linkage of Washington State Immunization Information System data and birth records.

METHODS

We conducted a retrospective cohort evaluation of children born in Washington from January 1, 2006 to November 12, 2019. We assessed up-to-date vaccination coverage status for measles, mumps, and rubella (MMR), diphtheria, tetanus, and pertussis (DTaP), and poliovirus vaccines at ages 36 months and 7 years. Children with ≥1 parent(s) born in selected non-US countries were compared with children with 2 US-born parents, using Poisson regression models to provide prevalence ratios.

RESULTS

We identified 902 909 eligible children, of which 24% had ≥1 non-US-born parent(s). Vaccination coverage at 36 months by PBC ranged from 41.0% to 93.2% for ≥1 MMR doses and ≥3 poliovirus doses and 32.6% to 86.4% for ≥4 DTaP doses. Compared with children of US-born parents, the proportion of children up to date for all 3 vaccines was 3% to 16% higher among children of Filipino-, Indian-, and Mexican-born parents and 33% to 56% lower among children of Moldovan-, Russian-, and Ukrainian-born parents. Within-PBC coverage patterns were similar for all vaccines with some exceptions. Similar PBC-level differences were observed at 7 years of age.

CONCLUSIONS

The linkage of public health data improved the characterization of community-level childhood immunization outcomes. The findings provide actionable information to understand community-level vaccination determinants and support interventions to enhance vaccine coverage.

Impact of pregnancy vaccine uptake and socio-demographic determinants on subsequent childhood Measles, Mumps and Rubella vaccine uptake: A UK birth cohort study

BACKGROUND

We examined the association between socio-demographic determinants and uptake of childhood Measles, Mumps & Rubella (MMR) vaccines and the association between pregnant women's pertussis vaccine uptake and their children's MMR vaccine uptake.

METHODS

We used nationally-representative linked mother-baby electronic records from the United Kingdom's Clinical-Practice-Research-Datalink. We created a birth cohort of children born between 01.01.2000 and 12.12.2020. We estimated the proportion vaccinated with first MMR vaccine by age 2 years and first and second MMR vaccines by age 5 years. We used survival-analysis and Cox proportional hazard models to examine the association between deprivation, ethnicity and maternal age and pertussis vaccination in pregnancy and children's MMR uptake.

RESULTS

Overall, 89.4 % (710,797/795,497) of children had first MMR by age 2 years and 92.6 % (736,495/795,497) by age 5 years. Among children still in the cohort when second MMR was due, 85.9 % (478,480/557,050) had two MMRs by age 5 years. Children from the most-deprived areas, children of Black ethnicity and children of mothers aged < 20 years had increased risk of being unvaccinated compared with children from the least-deprived areas, White children and children of mothers aged 31-40 years: first MMR by 5 years, adjusted Hazard Ratios (HR):0.86 (CI:0.85-0.87), HR:0.87 (CI:0.85-0.88) & HR:0.89 (CI:0.88-0.90) respectively. Deprivation was the determinant associated with the greatest risk of missed second MMR: adjusted HR:0.82 (CI:0.81-0.83). Children of mothers vaccinated in pregnancy were more likely than children of unvaccinated mothers to have MMR vaccines after adjusting for ethnicity, deprivation, and maternal age (First and Second MMRs adjusted HRs:1.43 (CI:1.41-1.45), 1.49 (CI:1.45-1.53).

CONCLUSION

Children from most-deprived areas are less likely to have MMR vaccines compared with children from least-deprived areas. Mothers who take up pregnancy vaccines are more likely to have their children vaccinated with MMR. Healthcare services should promote and facilitate access to both maternal and childhood vaccines during pregnancy.

Child Opportunity Index Disparities in Pediatric Surgical Encounters During the Coronavirus 2019 Pandemic

OBJECTIVE

Surgical encounters decreased during the coronavirus disease (COVID-19) pandemic and may have been deferred more in children with impeded health care access related to social/community risk factors. We compared surgery trends before and during the pandemic by Child Opportunity Index (COI).

METHODS

Retrospective analysis of 321,998 elective surgical encounters of children ages 0-to-18 years in 44 US children's hospitals from January 1, 2017 to December 31, 2021. We used auto-regression to compare observed versus predicted encounters by month in 2020-21, modeled from 2017 to 2019 trends. Encounters were compared by COI score (very low, low, moderate, high, very high) based on education, health/environment, and social/economic attributes of the zip code from the children's home residence.

RESULTS

Most surgeries were on the musculoskeletal (28.1%), ear/nose/pharynx (17.1%), cardiovascular (15.1%), and digestive (9.1%) systems; 20.6% of encounters were for children with very low COI, 20.8% low COI, 19.8% moderate COI, 18.6% high COI, and 20.1% very high COI. Reductions in observed volume of 2020-21 surgeries compared with predicted varied significantly by COI, ranging from -11.3% (95% confidence interval [CI] -14.1%, -8.7%) for very low COI to -2.6% (95%CI -3.9%, 0.7%) for high COI. Variation by COI emerged in June 2020, as the volume of elective surgery encounters neared baseline. For 12 of the next 18 months, the reduction in volume of elective surgery encounters was the greatest in children with very low COI.

CONCLUSIONS

Children from very low COI zip codes experienced the greatest reduction in elective surgery encounters during early COVID-19 without a subsequent increase in encounters over time to counterbalance the reduction.

'Unable to have a proper conversation over the phone about my concerns': a multimethods evaluation of the impact of COVID-19 on routine childhood vaccination services in London, UK

OBJECTIVES

Investigating the completion rate of 12-month vaccinations and parental perspectives on vaccine services during COVID-19.

STUDY-DESIGN

Service evaluation including parental questionnaire.

METHODS

Uptake of 12-month vaccinations in three London general practices during three periods: pre-COVID (1/3/2018-28/2/2019, n = 826), during COVID (1/3/2019-28/2/2020, n = 775) and post-COVID first wave (1/8/2020-31/1/2021, n = 419). Questionnaire of parents whose children were registered at the practices (1/4/2019-1/22/2021, n = 1350).

RESULTS

Comparing pre-COVID and both COVID cohorts, the completion rates of 12-month vaccines were lower. Haemophilus influenzae type B/meningococcal group C (Hib/MenC) vaccination uptake was 5.6% lower (89.0% vs 83.4%, P=<0.001), meningococcal group B (MenB) booster uptake was 4.4% lower (87.3% vs 82.9%, P = 0.006), pneumococcal conjugate vaccine (PCV) booster uptake was 6% lower (88.0% vs 82.0%, P < 0.001) and measles, mumps and rubella (MMR) vaccine uptake was 5.2% lower (89.1% vs 83.9%, P = 0.003). Black/Black-British ethnicity children had increased odds of missing their 12-month vaccinations compared to White ethnicity children (adjusted odds ratio 0.43 [95% confidence interval 0.24-0.79, P = 0.005; 0.36 [0.20-0.65], P < 0.001; 0.48 [0.27-0.87], P = 0.01; 0.40 [0.22-0.73], P = 0.002; for Hib/MenC, MenB booster, PCV booster and MMR. Comparing pre-COVID and COVID periods, vaccinations coded as not booked increased for MMR (10%), MenB (7%) and PCV booster (8%). Parents reported changes to vaccination services during COVID-19, including difficulties booking and attending appointments and lack of vaccination reminders.

CONCLUSION

A sustained decrease in 12-month childhood vaccination uptake disproportionally affected Black/Black British ethnicity infants during the first wave of the pandemic. Vaccination reminders and availability of healthcare professionals to discuss parental vaccine queries are vital to maintaining uptake.

Immunogenicity and safety of concomitant administration of the sabin-strain-based inactivated poliovirus vaccine, the diphtheria-tetanus-acellular pertussis vaccine, and measles-mumps-rubella vaccine to healthy infants aged 18 months in China

OBJECTIVES

During the COVID-19 pandemic, there was a decline in vaccine coverage, and the implementation of combined vaccines and co-administration strategies emerged as potential solutions to alleviate this predicament. Our objective is to delve into the concurrent administration of the sabin-strain-based inactivated poliovirus vaccine (sIPV), the diphtheria-tetanus-acellular pertussis vaccine (DTaP), and measles-mumps-rubella vaccine (MMR), with the intention of bridging the evidentiary gap pertaining to vaccine co-administration in Chinese infants, and to ensure a safe and effective vaccination strategy, ultimately leading to an augmentation in immunization coverage.

METHODS

This study was a follow-up trial of the "Immunogenicity and safety of concomitant administration of the sIPV with the DTaP vaccine in children: a multicenter, randomized, non-inferiority, controlled trial." Blood samples were collected on day 0 and day 30, and serum antibody levels were detected to measure antibody responses to each of the antigens. Local and systemic adverse events were monitored and compared among groups. This study is the first to fill the knowledge gap in China regarding the safe and effective combined vaccination of sIPV, DTaP, and MMR vaccines.

RESULTS

The geometric mean titer of the poliovirus types I, II, and III neutralizing antibodies were 1060.22 (95% CI: 865.73-1298.39), 1537.06 (95% CI: 1324.27-1784.05), and 1539.10 (95% CI: 1296.37-1827.29) in group I on day 30; geometric mean titer of antibodies against DTaP and MMR in the simultaneous vaccination group was non-inferior to those in the DTaP alone and MMR alone group. Reporting rates of local and systemic adverse reactions were similar between groups and no serious adverse events were reported throughout the clinical study period.

CONCLUSION

Co-administration of the sIPV, DTaP, and MMR was safe and did not impact immunogenicity, which would help to mitigate administrative costs and enhance vaccine coverage rates.

COVID-19 lockdown effect on healthcare utilization and in-hospital mortality in children under 5 years in Cape Town, South Africa: a cross-sectional study

BACKGROUND

COVID-19 pandemic measures resulted in the de-escalation of non-COVID-19 healthcare provision.

METHODS

A retrospective cross-sectional study of routinely collected data was done to investigate the effect of COVID-19 policies on the healthcare utilization and mortality of children younger than 5 years in Eastern Cape Town, South Africa. We compared visits to primary and urgent care facilities, hospitalization, in-hospital deaths, and vaccine uptake from 1 January to 31 December 2020 to similar periods in 2018 and 2019.

RESULTS

During April and May 2020, the most restricted period, visits to primary care facilities declined from 126 049 in 2019 to 77 000 (1.8-fold; p < 0.05). This corresponded with a 1.2-fold reduction in the provision of the first dose of measles vaccine at 6 months compared to 2019. Throughout 2020 there was a 4-fold decline in the number of fully immunized children at 1 year of age (p = 0.84). Emergency room visits fell by 35.7% in 2020 (16 368) compared to 2019 (25 446). Hospital admissions decreased significantly (p < 0.01) in 2020 (9810) compared to 2018 (11 698) and 2019 (10 247). The in-hospital mortality rate increased from 2.3% (96/4163) in 2019 to 3.8% (95/2498) (p < 0.01) in Tygerberg Hospital, where 80% (95/119) of deaths were recorded. Twelve of the 119 (10%) deaths occurred in HIV-positive children (p = <0.01).

CONCLUSION

Measures instituted during the COVID-19 pandemic disrupted access to healthcare services for children. This resulted in an immediate, and potential future, indirect effect on child morbidity and mortality in Cape Town.

Recurrent or unusual infections in children - when to worry about inborn errors of immunity

Recurrent infections are a common presenting feature in paediatrics and, while most times considered part of normal growing up, they are also a classical hallmark of inborn errors of immunity (IEI). We aimed to outline the value of currently used signs for IEI and the influence of the changing epidemiology of infectious diseases due to implementation of new vaccines and the effect of the COVID-19 pandemic on the assessment of children with recurrent infections. Warning signs for IEI have been developed, but the supporting evidence for their effectiveness is limited, and immune dysregulation is more commonly recognised as a feature for IEI, making reliable identification of children who should be screened for IEI on clinical grounds difficult. In addition, the epidemiology of infectious diseases is changing due to restrictions related to Covid-19 as well as immunisations, which may change the threshold to screen children for IEI. Treatments for IEI are evolving and are often more effective and less complicated when started early. Screening for IEI can be initiated by the non-immunologist and should be considered early to ensure optimal treatment outcomes.

Widening Disparities in Teen HPV Vaccinations during COVID-19 Pandemic: A Case Study from Veneto Region (Italy)

INTRODUCTION

In Local Health Unit 7, human papilloma virus (HPV) vaccination campaigns for 12-year-olds have long been implemented by the vaccination services of the Department of Prevention. Due to the pressure of the COVID-19 pandemic on these services, an emergency vaccination campaign was directly managed by primary care pediatricians (PCPs). An initial evaluation of this experience was conducted.

MATERIALS AND METHODS

Data on 12-year-olds assisted by PCPs belonging to the 2006 (pre-pandemic) and 2008 (pandemic) birth cohorts were extracted, along with HPV vaccination data. Health district, gender, citizenship, socioeconomic status, and PCPs were evaluated as possible influencing factors in a two-level logistic regression (second level: single PCP).

RESULTS

The HPV vaccination gap between males and females increased significantly for the 2008 birth cohort compared to the 2006 birth cohort (11 vs. 4 percentage points). As for PCPs, the vaccination uptake range was 4-71% for the 2008 birth cohort vs. 32-85% for the 2006 cohort. The proportion of variance explained at the second level was overall equal to 9.7% for the 2008 cohort vs. 3.6% for the 2006 cohort.

CONCLUSIONS

The vaccination campaign carried out during the peak of the COVID-19 pandemic increased the HPV vaccination gaps among Health Districts, genders, and individual PCPs, probably due to a lack of homogeneity in professional practices and attitudes toward HPV vaccination. Catch-up interventions are required in the immediate term, while an equity-lens approach should be taken for reprogramming the vaccination campaign. Greater involvement of schools and families could ensure a more equitable approach and a better uptake.

Impact of the COVID-19 pandemic on timeliness and equity of measles, mumps and rubella vaccinations in North East London: a longitudinal study using electronic health records

OBJECTIVES

To quantify the effect of the COVID-19 pandemic on the timeliness of, and geographical and sociodemographic inequalities in, receipt of first measles, mumps and rubella (MMR) vaccination.

DESIGN

Longitudinal study using primary care electronic health records.

SETTING

285 general practices in North East London.

PARTICIPANTS

Children born between 23 August 2017 and 22 September 2018 (pre-pandemic cohort) or between 23 March 2019 and 1 May 2020 (pandemic cohort).

MAIN OUTCOME MEASURE

Receipt of timely MMR vaccination between 12 and 18 months of age.

METHODS

We used logistic regression to estimate the ORs (95% CIs) of receipt of a timely vaccination adjusting for sex, deprivation, ethnic background and Clinical Commissioning Group. We plotted choropleth maps of the proportion receiving timely vaccinations.

RESULTS

Timely MMR receipt fell by 4.0% (95% CI: 3.4% to 4.6%) from 79.2% (78.8% to 79.6%) to 75.2% (74.7% to 75.7%) in the pre-pandemic (n=33 226; 51.3% boys) and pandemic (n=32 446; 51.4%) cohorts, respectively. After adjustment, timely vaccination was less likely in the pandemic cohort (0.79; 0.76 to 0.82), children from black (0.70; 0.65 to 0.76), mixed/other (0.77; 0.72 to 0.82) or with missing (0.77; 0.74 to 0.81) ethnic background, and more likely in girls (1.07; 1.03 to 1.11) and those from South Asian backgrounds (1.39; 1.30 to 1.48). Children living in the least deprived areas were more likely to receive a timely MMR (2.09; 1.78 to 2.46) but there was no interaction between cohorts and deprivation (Wald statistic: 3.44; p=0.49). The proportion of neighbourhoods where less than 60% of children received timely vaccination increased from 7.5% to 12.7% during the pandemic.

CONCLUSIONS

The COVID-19 pandemic was associated with a significant fall in timely MMR receipt and increased geographical clustering of measles susceptibility in an area of historically low and inequitable MMR coverage. Immediate action is needed to avert measles outbreaks and support primary care to deliver timely and equitable vaccinations.