Objective: To describe the influenza-related morbidity and mortality in healthy children aged under 5 years in South Australia, in order to further understand the potential role of influenza vaccination.
Design and setting: We undertook a descriptive analysis of SA hospital separations data and Australian Bureau of Statistics death data for children aged under 5 years admitted to hospital for influenza. All diagnoses related to an influenza admission were examined to determine whether children were at risk of complications from influenza, according to the criteria of the National Health and Medical Research Council.
Main outcome measures: Mean influenza admission rates per 100 000 population per year in children aged under 5 years between 1996 and 2006, and the proportion of children admitted to hospital who did not have a secondary diagnosis putting them at higher risk of influenza-related complications.
Results: From 1996 to 2006, 649 children aged under 5 years were admitted to hospital for influenza. Mean annual admission rates per 100 000 were highest in children aged under 1 year (151.0), and decreased with age. Aboriginal and Torres Strait Islander children aged under 5 years had a mean admission rate of 161.8 per 100 000. Most children under 5 years (81%) admitted to hospital did not have an underlying illness that would put them at risk of influenza-related morbidity.
Conclusion: Healthy children aged under 2 years and Aboriginal and Torres Strait Islander children under 5 years old have high rates of hospital admission, which may have implications for the target group recommendations for influenza immunisation. Currently, vaccination is recommended only for children with specified chronic diseases.
- 1. Beard F, McIntyre P, Gidding H, et al. Influenza related hospitalisations in Sydney, New South Wales, Australia. Arch Dis Child 2006; 91: 20-25.
- 2. Bueving H, van der Wouden J, Berger M, et al. Incidence of influenza and associated illness in children aged 0–19 years: a systematic review. Rev Med Virol 2005; 15: 383-391.
- 3. Izurieta H, Thompson WW, Kramarz P, et al. Influenza and the rates of hospitalization for respiratory disease among infants and young children. N Engl J Med 2000; 342: 232-240.
- 4. Neuzil KM, Mellen BG, Wright PF, et al. The effect of influenza on hospitalizations, outpatient visits, and courses of antibiotics in children. N Engl J Med 2000; 342: 225-231.
- 5. Bhat N, Wright JG, Broder KR, et al. Influenza-associated deaths among children in the United States, 2003–2004. N Engl J Med 2005; 353: 2559-2567.
- 6. Milne B, Williams S, May M, et al. Influenza A associated morbidity and mortality in a paediatric intensive care unit. Commun Dis Intell 2004; 28: 504-508.
- 7. National Health and Medical Research Council. The Australian immunisation handbook. 8th ed. Canberra: NHMRC, 2003.
- 8. Brotherton J, McIntyre P, Puech M, et al. Vaccine preventable diseases and vaccination coverage in Australia, 2001 to 2002. Commun Dis Intell 2004; 28 Suppl 2: vii-S116.
- 9. Menzies R, McIntyre P, Beard F. Vaccine preventable diseases and vaccination coverage in Aboriginal and Torres Strait Islander people, Australia, 1999 to 2002. Commun Dis Intell 2004; 28 Suppl 1: S1-S45.
- 10. Keren R, Wheeler A, Coffin S, et al. ICD-9 codes for identifying influenza hospitalizations in children. Emerg Infect Dis 2006; 12: 1603-1604.
- 11. Salgado C, Farr B, Hall K, Hayden F. Influenza in the acute hospital setting. Lancet Infect Dis 2002; 2: 145-155.
- 12. Isaacs D. Should all Australian children be vaccinated against influenza? Med J Aust 2005; 182: 553-554. <MJA full text>
- 13. Smith S, Demicheli V, Di Pietrantonj C, et al. Vaccines for preventing influenza in healthy children. Cochrane Database Syst Rev 2006; (1): CD004879.
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