Impact of the introduction of a universal childhood influenza vaccination programme on influenza-related admissions to paediatric intensive care units in England

Abstract

IntroductionA universal childhood influenza vaccination programme was introduced in the UK in September 2013. We examine the impact of the gradual introduction of this programme on influenza-related paediatric intensive care unit (PICU) admission rates in England.MethodsWe extracted data on all influenza-related admissions to PICUs in England in resident children aged 0–15 years old between October 2003 and March 2017 from the Paediatric Intensive Care Audit Network (PICANet) database. We estimated influenza-associated PICU admission rates per 100 000 children by age group, sex and winter season (October to March), and used Poisson regression models to estimate incidence rate ratios (IRRs) in the winter seasons since the introduction of universal childhood vaccination compared with the two winters before the introduction of the programme (2011–2013).ResultsWe identified 929 influenza-related PICU admissions among 873 children. 48.3% of admissions were among children aged less than 2 years old. The influenza-associated PICU admission rate was 1.32 per 100 000 children (95% CI 1.23 to 1.40). We identified a significant increase in influenza PICU admissions in the winters following the introduction of the universal childhood vaccination programme compared with the winters of 2010/2011–2012/2013 among children aged <5 years old: IRR 1.58 (1.05, 2.37) in children <1 year, 2.71 (1.43, 5.17) in 1 year-olds and 1.98 (1.18, 3.31) in children 2–4 years old. No significant difference was found among children aged 5–15 years.ConclusionThe universal childhood influenza vaccination has not yet reduced the influenza-associated burden on PICUs in England during its early phase of introduction. Monitoring of influenza PICU admission rates needs to continue in England to assess the long-term impact of universal paediatric influenza vaccination. Linkage between PICANet and national infection surveillance databases would better enable such monitoring.

Uptake and impact of vaccinating primary school children against influenza: Experiences in the fourth season of the live attenuated influenza vaccination programme, England, 2016/2017

“…Non‐significant reductions were noted amongst primary school aged children for primary care consultations and swab positivity, secondary care swab positivity, laboratory confirmed hospitalisations and ED attendances. As shown previously and in other studies, it continues to be evident that the impact and greater effect sizes are in primary care indicators in comparison to those in secondary care, in both targeted and non‐targeted populations 26–29 …”

“…As shown previously and in other studies, it continues to be evident that the impact and greater effect sizes are in primary care indicators in comparison to those in secondary care, in both targeted and non-targeted populations. [26][27][28][29] Findings from historical trends for GP ILI consultations, hospitalisations and ICU/admissions suggest significant differences post-programme introduction in GP ILI consultations in all age groups; however, these differences should be interpreted with caution due to pre-existing differences between the pilot and non-pilot areas prior to the programme. Nonetheless, as seen previously, reductions remain evident in targeted populations and there continues to be evidence that an indirect effect on the <5 year olds is present.…”

“…As shown previously and in other studies, it continues to be evident that the impact and greater effect sizes are in primary care indicators in comparison to those in secondary care, in both targeted and non‐targeted populations. 26 , 27 , 28 , 29…”

Human metapneumovirus in paediatric intensive care unit (PICU) admissions in the United Kingdom (UK) 2006–2014

“…A similar study using PICAnet data looking at PICU admissions related to influenza between October 2003 and March 2017 showed an average of 64 PICU admissions per year. Assuming an average of 16,000 PICU admissions per year this would account for approximately 4 per 1000 PICU admissions [23]. Similar data for UK PICU admissions related to RSV are not available, however, one study has investigated all cause bronchiolitis admissions to UK PICUs.…”