Skip to main content

Risk factors for influenza-related complications in children during the 2009/10 pandemic: a UK primary care cohort study using linked routinely collected data

  • J. J. Lee (a1), C. Bankhead (a1), M. Smith (a1), A. A. Kousoulis (a2), C. C. Butler (a1) and K. Wang (a1)...

Primary care clinicians have a central role in managing influenza/influenza-like illness (ILI) during influenza pandemics. This study identifies risk factors for influenza-related complications in children presenting with influenza/ILI in primary care. We conducted a cohort study using routinely collected linked data from the Clinical Practice Research Datalink on children aged 17 years and younger who presented with influenza/ILI during the 2009/10 pandemic. We calculated odds ratios (ORs) for potential risk factors in relation to influenza-related complications, complications requiring intervention, pneumonia, all-cause hospitalisation and hospitalisation due to influenza-related complications within 30 days of presentation. Analyses were adjusted for potential confounders including age, vaccination and socio-economic deprivation. Asthma was a risk factor for influenza-related complications (adjusted OR 1.48, 95% confidence interval (CI) 1.21–1.80, P < 0.001), complications requiring intervention (adjusted OR 1.44, 95% CI 1.11–1.88; P = 0.007), pneumonia (adjusted OR 1.64, 95% CI 1.07–2.51, P = 0.024) and hospitalisation due to influenza-related complications (adjusted OR 2.46, 95% CI 1.09–5.56, P = 0.031). Neurological conditions were risk factors for all-cause hospitalisation (adjusted OR 4.25, 95% CI 1.50–12.07, P = 0.007) but not influenza-related complications (adjusted OR 1.46, 95% CI 0.83–2.56, P = 0.189). Community-based early interventions to prevent influenza-related clinical deterioration should therefore be primarily targeted at children with asthma and neurological conditions.

Corresponding author
Author for correspondence: Dr Joseph Lee, E-mail:
Hide All
1.Kunin, M, et al. (2015) Challenges of the pandemic response in primary care during pre-vaccination period: a qualitative study. Israel Journal of Health Policy Research 4, 32.
2.Department of Health. Immunisation against infectious disease. Chapter 19: Influenza. Available at (21st April 2017). (Accessed 28 August 2015).
3.Prevention and Control of Seasonal Influenza with Vaccines. Recommendations of the Advisory Committee on Immunization Practices – United States, 2016–17 Influenza Season. Available at (Accessed 14 August 2017).
4.Goossens, H, et al. (2005) Outpatient antibiotic use in Europe and association with resistance: a cross-national database study. Lancet 365(9459), 579587.
5.Stephenson, I, et al. (2009) Neuraminidase inhibitor resistance after oseltamivir treatment of acute influenza A and B in children. Clinical Infectious Diseases 48(4), 389396.
6.Fleming, DM, et al. (2016) Influenza-attributable burden in United Kingdom primary care. Epidemiology and Infeciont 144(3), 537547.
7.Anon. Joint Committee on Vaccination and Immunisation – Minutes of the meeting held on Friday 13 April 2012. Available at (Accessed 14 August 2017).
8.Green, HK, et al. (2016) Illness absenteeism rates in primary and secondary schools in 2013–2014 in England: was there any impact of vaccinating children of primary-school age against influenza? Epidemiology and Infecttion 144(16), 34123421.
9.Yin, JK, et al. (2017) Systematic review and meta-analysis of indirect protection afforded by vaccinating children against seasonal influenza: implications for policy. Clinical Infectious Diseases 65(5), 719728. doi: 10.1093/cid/cix1420.
10.Lim, WS (2007) Pandemic flu: clinical management of patients with an influenza-like illness during an influenza pandemic. Thorax 62, 146.
11.Gill, PJ, et al. (2015) Identification of children at risk of influenza-related complications in primary and ambulatory care: a systematic review and meta-analysis. Lancet Respiratory Medicine 3(2), 139149.
12.Herrett, E, et al. (2015) Data resource profile: Clinical Practice Research Datalink (CPRD). International Journal of Epidemiology 44(3), 827836.
13.Herbert, A, et al. (2017) Data resource profile: Hospital Episode Statistics admitted patient care (HES APC). International Journal of Epidemiology 46(4), 10931093i. doi: 10.1093/ije/dyx1015.
14.Meier, CR, et al. (2000) Population-based study on incidence, risk factors, clinical complications and drug utilisation associated with influenza in the United Kingdom. European Journal of Clinical Microbiology and Infectious Diseases 19, 834842.
15.SIGN 153 British guideline on the management of asthma. September 2016. Available at (Accessed 11 May 2017).
16.Li-Kim-Moy, J, et al. (2017) Influenza hospitalizations in Australian children. Epidemiology and Infecttion 145(7), 14511460.
17.Mertz, D, et al. (2013) Populations at risk for severe or complicated influenza illness: systematic review and meta-analysis. British Medical Journal 347, f5061. doi: 5010.1136/bmj.f5061.
18.Millman, AJ, et al. (2016) Community-Acquired pneumonia hospitalization among children with neurologic disorders. Journal of Pediatrics 173, 188195.e184.
19.National Institute for Health and Care Excellence (NICE). Neutropenic sepsis: prevention and management in people with cancer. Clinical guideline [CG151] Published date: September 2012.
20.Little, P, et al. (2005) Information leaflet and antibiotic prescribing strategies for acute lower respiratory tract infection: a randomized controlled trial. JAMA 293(24), 30293035.
21.Hardelid, P, et al. (2015) Recording of influenza-like illness in UK primary care 1995-2013: cohort study. PLoS ONE 10(9), e0138659.
22.Rutter, P, et al. (2014) Access to the NHS by telephone and internet during an influenza pandemic: an observational study. BMJ Open 4, e004174.
23.Maeda, S, et al. (1999) Efficacy of antibiotics against influenza-like illness in an influenza epidemic. Paediatrics International 41, 274276.
24.Smith, M, et al. (2015) Influenza vaccination in children with neurologic or neurodevelopmental disorders. Vaccine 33(20), 23222327.
25.Hardelid, P, et al. (2017) Risk factors for admission to hospital with laboratory-confirmed influenza in young children: birth cohort study. The European Respiratory Journal 50(3), 111.
26.Public Health England. The national childhood Flu immunisation programme 2017/18. Published July 2017. Available at (Accessed 20 November 2017).
27.Pebody, R, et al. (2016) Effectiveness of seasonal influenza vaccine for adults and children in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2015/16 end-of-season results. Euro Surveillance 21(38). doi: 10.2807/
28.Rajaram, S, et al. (2016) Uptake of childhood influenza vaccine from 2012-2013 to 2014-2015 in the UK and the implications for high-risk children: a retrospective observational cohort study. BMJ Open 6(8), e010625.
29.Verbakel, JY, et al. (2016) Should all acutely ill children in primary care be tested with point-of-care CRP: a cluster randomised trial. BMC Medicine 14(1), 131. doi: 110.1186/s12916-12016-10679-12912.
30.Brendish, NJ, et al. (2017) Routine molecular point-of-care testing for respiratory viruses in adults presenting to hospital with acute respiratory illness (ResPOC): a pragmatic, open-label, randomised controlled trial. Lancet Respiratory Medicine 5(5), 401411.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Type Description Title
Supplementary materials

Lee et al. supplementary material
Lee et al. supplementary material

 Word (40 KB)
40 KB


Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed