Immunisation is one of the most important and effective strategies in public health.1 A nationally funded National Immunisation Program schedule, combined with the Australian Childhood Immunisation Register (ACIR), has markedly increased vaccination coverage over the past decade. Australia wide in 2005, 92% of children had received all routine schedule vaccines at 2 years of age.2 Timeliness, or administering vaccines at the recommended age, has become more of a priority as immunisation coverage has improved. This is an increasing challenge in an ever more crowded schedule, with five new vaccines added to the National Immunisation Program schedule since 2003.
Attendance at any health-care contact provides opportunities to assess a child's immunisation status and potentially catch-up on any vaccines that may be due or overdue. As highlighted by Ressler et al. in this edition of the Journal, unfortunately in hospitals many of these opportunities are ‘missed’.3 Missed opportunities to vaccinate can be defined as when ‘a child is identified as being eligible for vaccination during the visit, with no contraindication for vaccination, but failed to receive the needed dose(s)’.4 Ressler et al. also noted that the critical first step of identifying that catch-up vaccinations are required is often not occurring. This is despite immunisations being part of the standardised national paediatric clinical indicators, introduced through the Australian Council of Healthcare Standards.
In the community, barriers to immunisation include: access to services, waiting times and duration of appointments. None of these barriers exist in hospital where the admission process, even if for less than 1 day, provides time to take an immunisation history, verify this against official records and update the records, or give immunisations before discharge as appropriate. In some community-based studies missed opportunities to vaccinate have been as high as 50% of visits.5 A hospital study targeting junior doctors found 14% of inpatients had a missed opportunities for an age-appropriate immunisation.6 This study by Ressler et al. was based on nursing assessments, but similarly found 24% of vaccination opportunities were missed. This suggests that current mechanisms to identify and vaccinate children entering or already in hospital are not overly effective and new strategies are required.
Social determinants also effect vaccination status, with those not up-to-date (UTD) generally being more socially disadvantaged and with less access to health-care services. This is particularly the case in those partially immunised, with the Millennium cohort study in the United Kingdom finding this group were more likely to be socially disadvantaged, have single or teenage parents and be from an ethnic minority.7 Interestingly, the study also found that admission to hospital by 9 months of age was independently associated with partial immunisation, highlighting this as an opportunity to vaccinate a vulnerable group. Concerns over vaccine safety may also affect immunisation status and these issues need to be discussed on individual basis and specialised advice sought if required.
Missed opportunities to vaccinate can take on a number of forms. A US multicentre survey found failure to give all vaccines simultaneously accounted for up to 15% of missed opportunities. Missed opportunities were three times more likely to occur during sick or unwell child visits in primary care.8 As Ressler et al. conducted a hospital study, they were predominantly unwell visits at presentation, but assessment just before discharge for example may have been an opportunity for catch-up vaccinations to be given. Not giving all needed vaccines simultaneously will lead to a child being more likely to remain not UTD, particularly in the absence of a clear vaccination catch-up plan. True contraindications to vaccination are few, but need to be considered in hospitalised patients, for example, those who are immunocompromised. Missed opportunities to vaccinate when true contraindications do not exist will leave patients who may already be in a high-risk group vulnerable to vaccine preventable diseases.
While Ressler et al. focused on routine-scheduled immunisations, many children admitted to hospital are also part of ‘special risk groups’, such as ex-preterm infants who may require additional doses of specific vaccines (e.g. hepatitis B if born <32 weeks gestation). The vaccination requirements of these special risk groups are outlined in the Australian Immunisation Handbook.9 For example, some children with a chronic illness are recommended to have annual influenza vaccination and a pneumococcal vaccine booster at 4–5 years of age, so these groups need to be identified at health-care visits. Immunisation discussions should also include consideration of newer vaccines such as varicella if the patient does not have a history of clinical infection or vaccination.
So how can missed opportunities to vaccinate be addressed? A systematic review by Jacobson et al. has shown that almost all patient reminder systems will produce an improvement in immunisation UTD status, ranging from 1% to 20%.10 These were predominantly in primary care settings and telephone reminders were the most effective, but also the most expensive intervention. Postcards were also effective and reminders worked whether it was from a private or public clinic. ACIR currently sends out letters to parents whose child is overdue and linking this to government-funded payments has also contributed to the improved vaccination coverage in Australia today. Missed opportunities are still occurring; however, so new additional strategies are required. Using electronic health records with an immunisation alert has also been shown to markedly improve UTD status by more than 8%.11 Paper-based health records still predominate in Australian hospitals and outpatient clinics, but with progression to electronic records, opportunities exist to make immunisation status one of the key performance benchmarks in utilising this technology.
Effective use of electronic immunisation records such as ACIR was also highlighted by Ressler et al. as an essential component to address missed opportunities to vaccinate. Currently, ACIR only captures vaccinations on the routine schedule for children under 7 years of age. The push to make it a lifelong register is gaining momentum and this will mean missed opportunities to vaccinate could be minimised not only for children but also for adults.12 The introduction of new vaccines such as HPV to the National Immunisation Program in April 2007 has highlighted the benefit of developing links between immunisation status and other databases; in this case, the cervical cancer registry. This would be much easier to do with a whole of life immunisation register and allow vaccination programmes to be more systematically implemented and assessed. Available access to ACIR (currently requiring a software download and individual password) on hospital wards and in outpatient clinics needs to broaden if this resource is to be used effectively.
In summary, improved procedures in hospital and in community health-care settings need to be put in place to both identify and then minimise the number of missed opportunities to vaccinate. This should be in conjunction with education of health-care professionals as well as patients and their families. Education alone, however, has been shown to be of uncertain benefit and system changes or improved processes are required to produce an actual change in practice.13 The following considerations are some of those that need to be addressed to minimise missed opportunities to vaccinate:
- • Immunisation status according to the child's age and medical condition should be assessed at each health-care contact.
- • Only true medical contraindications should delay immunisations.
- • Needed vaccines should be administered simultaneously to avoid confusion and further missed opportunities.
- • All vaccinations should be recorded in the personal health record as well as in ACIR.
- • ACIR needs to be readily available to all health-care providers.