Welcome to the WSPID 2022 Virtual Congress Calendar

Background

Despite vaccination being one of the great global public health successes, uptake amongst children and young people (CYP) remains below WHO targets for many diseases. UK guidance recommends vaccination status be checked routinely in all healthcare settings, e.g. the Paediatric Emergency Department (PED). This is most commonly done via a basic question such as “Is this child up-to-date?”.

Aims

The aim of this work was to estimate the accuracy of parent/carer recall (the routine source of data during a PED consultation). It is part of a project exploring the potential for PED-based vaccination interventions, with an initial focus on ways of reliably identifying those at higher risk of being under-immunised.

Methods

Full ethics approval was obtained. Participants were recruited from attendees (< 16 years old) at one PED in England. Parents/carers were asked if the attendee was up-to-date with vaccinations (yes/no/not sure) and consent was requested to access community-held vaccination records (assumed to be correct as vaccines are mostly given in the community).

Results

Only 4% of CYP were reported by parents/carers as not being fully immunised, however community-held records showed this figure to be 14%. Nearly one in five (18%) of parents/carers inaccurately reported their child’s status, with the majority over-estimating vaccination coverage.

Conclusions

CYP attending the PED may benefit from targeted interventions to improve their vaccination coverage. However, parent/carer recall is not sufficiently reliable as a source of accurate vaccination data. More work needs to be done to look at alternative sources of data for identifying under-vaccinated CYP during a PED visit.

Background

In countries with pediatric pneumococcal conjugate vaccine (PCV) national immunization programs (NIPs), some children remain unvaccinated or partially vaccinated with PCV. Incompletely vaccinated children may be at an increased risk of pneumococcal disease compared with children fully vaccinated with the recommended three or four dose PCV schedule.

Aims

Estimate the number of children born in countries with PCV NIPs who are unvaccinated or partially vaccinated.

Methods

Adherence to PCV recommended schedules were obtained from the latest year of the World Health Organization’s complete first (PCV1), second (PCV2), and final (PCV3) dose data by country. The calculated percentages of children who received no, one, or two PCV dose(s) in the series were multiplied by each country’s 2019 birth cohort. The number of children receiving no, one, or two PCV dose(s) by country was summed to estimate the global percentage of unvaccinated or partially vaccinated children.

Results

Globally, an estimated 14.9%, 4.0%, and 6.8% of children born in countries with PCV NIPs complete no, one, or two doses of the PCV series, respectively (Table 1). This equates to approximately 15.0 million unvaccinated children and 10.9 million partially vaccinated children across PCV-eligible countries in 2019. Overall, countries in Asia, Africa, the Middle East, and Latin America with larger birth cohorts had a higher number of incompletely vaccinated children (Table 2).

Conclusions

Of children born in countries with PCV NIPs, nearly 26% are unvaccinated or partially vaccinated with PCVs. Country-specific tactics should be explored to increase PCV vaccination rates and subsequent vaccine impact.

Background

Lack of a timely receipt of vaccines causes challenges such as uncertain immune response and under-vaccination. Hence, timely vaccination is crucial to ensure an infant’s early protection.

Aims

To identify the age of presentation for the birth dose vaccination, vaccine antigens received, and determinants of timely presentation for vaccinations in Northern Nigeria.

Methods

A descriptive cross-sectional study involving 1952 mother-infant pairs enrolled from five different states in Northern Nigeria. Data collected include the socio-demographic, antenatal care (ANC) and delivery details, dates of birth, presentation for vaccination, and birth vaccine antigens received. Data analysis was done with SPSS-21.

Results

The median age of the infants at presentation for the birth dose vaccines was six (interquartile range 2-16) days. 413 (21.2%) mother-infant pairs presented on the day of birth (Day 0) or the next day (Day 1), while one-fifth (403, 20.6%) mother-infant pairs came after Day 28. The Bacille-Calmette-Guerin vaccine was most frequently received at 91.2% (1781 infants), oral polio vaccine 1703(87.2%) and hepatitis B vaccine birth dose (HBV-BD) the lowest at 75.1% (1565). The commonest reasons proffered for the delayed presentations were an ill baby (24.7%) and an ill mother, 21.9%. Determinants of presentation within 24 hours post-birth were hospital delivery (OR-1.67, 95% CI; 1.28-2.19), first child (OR-1.4; 95%CI; 1.02-1.93), Christianity (OR-2.141 95%C.I; 1.63-2.81) and mother with tertiary education (OR-1.62, 95%CI; 1.05-2.48).

Conclusions

Timely presentation for birth dose vaccines is low in Northern Nigeria. Furthermore, some babies do not get the required vaccines despite presenting for vaccination.Missed opportunities due to vaccine unavailability is a concern.

Background

Due to COVID-19 pandemic restrictions, health-related concerns, and lockdowns, routine adolescent immunization rates declined substantially.

Aims

We sought to assess whether online education would improve pediatricians' knowledge, competence, and confidence related to adolescent vaccinations.

Methods

Pediatricians participated in a 30-minute video lecture. Educational effect was assessed using a repeated-pair design with pre-/post-assessment. 3 questions assessed knowledge/competence, and 1 question rated on a Likert-type scale assessed confidence. A paired-samples t-test was conducted for significance testing on the overall average number of correct responses and for confidence rating, and a McNemar’s test was conducted at the question level (5% significance level, P <.05). Cohen’s d with correction for paired samples estimated the effect size of the education on the number of correct responses (<.20 modest, .20-.49 small, .59-.79 moderate, ≥.80 large). Data were collected from 12/11/20 to 3/1/21.

Results

Average knowledge/competence improved from 50% to 59% (N= 1,777, P<.001, Cohen’s d = 0.34) among pediatricians.

Relative improvements post-participation in specific areas were as follows (P<.001):

10% improvement among pediatricians in findings related to identifying vaccines routinely recommended by the Advisory Committee on Immunization Practices (ACIP).

28% improvement among pediatricians related to correctly identifying if a 9-year old male patient is eligible for the HPV vaccine.

35% of pediatricians had a measurable increase in confidence in their ability to collaborate with the interprofessional team to increase vaccine uptake among adolescents during the pandemic.

Conclusions

This study demonstrated the success of a 30-minute video lecture at improving pediatrician's knowledge, competence, and confidence related to recommendations for adolescent vaccines.

Background

Vaccine hesitancy contributes significantly to suboptimal vaccination of infants from low wealth quintile families in Nigeria and the different strategies that have been employed to address it are yet to yield satisfactory outcomes. Older women infant caregivers are unrecognized stakeholders in infant care despite their cultural and strategic relevance in infant care. Exploring their views about vaccine hesitancy may offer better understanding of the phenomenon within the local context and guide the design of appropriate interventions.

Aims

To explore the views of older women caregivers regarding vaccine hesitancy and describe their experiences and handling of the same in seven urban slum communities of Ibadan, Nigeria.

Methods

Exploratory qualitative study design was used, and data was obtained using 22 focus group discussions among older women (≥35 years). Data was transcribed, and thematic analysis was used to analyze the data.

Results

The older women described vaccine hesitancy as complete avoidance of vaccine, but many did not view delayed or incomplete infant vaccination as vaccine hesitancy. They had all witnessed or experienced vaccine hesitancy in the past and believed it was due to ignorance, misinformation, and lack of trust in government policies. Vaccine hesitancy have been handled by reporting offending parents to community health committees, threatening and educating such parents by the older women.

Conclusions

Older women infant caregivers studied did not recognize the full spectrum of vaccine hesitancy and were handling it using ineffective means. Training these older women about vaccine hesitancy may improve infant vaccination in Nigerian slum communities.

Background

Lower antibody response to the COVID-19 vaccine has been reported in immunocompromised adults. However, data on the humoral and cellular immune response among immunocompromised adolescents are scarce.

Aims

To evaluate the humoral and cellular immune response to the BNT162b2 vaccine in immunocompromised adolescents.

Methods

This prospective cohort study included immunocompromised adolescents aged 12 to 18 years. Two doses of BNT162b2 were administered 21 days apart. The humoral immune response was assessed by surrogate virus neutralization test (sVNT) against Delta variant before and 4 weeks after the second dose. In addition, the ELISpot was used to determine cellular immune response against the S protein. A threshold of > 95 spot-forming units (SFUs)/10⁶ peripheral blood mononuclear cells (PBMCs) indicates detectable T-cell responses.

Results

Thirty-seven immunocompromised adolescents included 8 kidney transplants, 11 bone marrow transplants, 16 rheumatologic disorders, and 2 cancer patients with a median age of 15.6 years (IQR 14.2, 17.8), were enrolled. Among 37 patients, only 3 (8.1%) and 23 (62.2%) patients achieved sVNT > 80% inhibition after the first and the second dose, respectively. Additionally, 29 (76.3%) patients demonstrated T-cell responses with the median spike-specific T-cell response of 220 (IQR 100, 428) SFUs/10⁶ PBMCs. However, there was no correlation between sVNT and the magnitude of T-cell responses (Spearman’s rho: 0.18; P=0.28).

Conclusions

Two-third of immunocompromised adolescents developed humoral immune response after 2 doses of BNT162b2, but discordance between sVNT and T-cell responses was observed. Therefore, assessing only the humoral response may underestimate the immunogenicity of the vaccine.