Establishing an opportunistic catch up immunisation service for children attending an acute trust in London

Vaccine-preventable disease susceptibility in a British paediatric assessment unit

Aims: To evaluate practice within a paediatric secondary-care centre before and after introduction of simple interventions to improve identification of under-immunised children and facilitate catch-up immunisations. Methods: The population-based child health database was used to check immunisation status for two cohorts of 200 consecutive admissions before and after routine printing of immunisation histories from the database and raising staff awareness. Vaccine-preventable disease (VPD) susceptibility burdens were calculated for each child. Case notes were assessed for accuracy and documentation of ward-based interventions. Results: Fourteen per cent of all children were under-immunised on admission and 27% of these were more than five years behind schedule. Under-immunised children's VPD susceptibility burdens ranged from 0-40,858 days and in 59% exceeded 1,000 days. Over one month the paediatric admission unit saw children with a combined VPD susceptibility burden of 1,323 child-years. Positive identification of under-immunised children increased by 40% (95% confidence interval: 12-62, p=0.002) following the introduction of routine database printouts. Conclusion: Children presenting to British secondary care units have large VPD susceptibility burdens. Positive identification of under-immunised children substantially improved after the introduction of routine database printouts, but catch-up immunisation rates did not increase.

Using routinely collected data to improve immunisation histories

Immunisation is one of the most effective health interventions in existence yet outbreaks of vaccine-preventable diseases continue to occur in developed countries. High rates of cover are needed to provide adequate herd immunity and there is evidence that a significant proportion of paediatric inpatients are not up to date even in areas with high levels of community cover. A proportion of these children will have parents who consciously declined immunisation, however the remaining children represent a vulnerable cohort whose under-immunisation is not routinely identified.

Two-hundred consecutive admissions to rural paediatric assessment unit had their routinely documented vaccination histories checked against their records on the regional Child Health Information System (CHIS). 30 children (15%) were not up to date on the CHIS, yet routine clerking only identified 5 of these children (17%). After introduction of a simple system whereby ward clerks and doctors were taught how to access and print full immunisation histories from the CHIS, a further 200 consecutive admissions were audited. A similar number were not up to date (29/200) but the proportion of children with missing immunisations correctly identified in the clerking documentation increased to 52% (15 children). This is a 35% improvement (95% CI; 12–58%).

Access to routinely collected data can significantly improve identification of under-immunised children and contribute towards higher levels of individual and herd-immunity.