- Anthony Harnden (), university lecturer1,
- Cameron Grant, associate professor of paediatrics2,
- Timothy Harrison, deputy director3,
- Rafael Perera, senior research fellow in statistics1,
- Angela B Brueggemann, senior research fellow in molecular biology1,
- Richard Mayon-White, epidemiologist1,
- David Mant, professor of general practice1
- 1 Department of Primary Health Care, University of Oxford, Oxford OX3 7LF,
- 2 Department of Paediatrics, University of Auckland, Starship Children's Hospital, Auckland, New Zealand,
- 3 Respiratory and Systematic Infection Laboratory, Health Protection Agency, Centre for Infections, London NW9 5HT
- Correspondence to: A Harnden
- Accepted 3 May 2006
Objective To estimate the proportion of school age children with a persistent cough who have evidence of a recent Bordetella pertussis infection.
Design Prospective cohort study (October 2001 to March 2005).
Setting General practices in Oxfordshire, England.
Participants 172 children aged 5-16 years who presented to their general practitioner with a cough lasting 14 days or more who consented to have a blood test.
Main outcome measures Serological evidence of a recent Bordetella pertussis infection; symptoms at presentation; duration and severity of cough; sleep disturbance (parents and child).
Results 64 (37.2%, 95% confidence interval 30.0% to 44.4%) children had serological evidence of a recent Bordetella pertussis infection; 55 (85.9%) of these children had been fully immunised. At presentation, children with whooping cough were more likely than others to have whooping (odds ratio 2.85, 95% confidence interval 1.39 to 5.82), vomiting (4.35, 2.04 to 9.25), and sputum production (2.39, 1.14 to 5.02). Children with whooping cough were also more likely to still be coughing two months after the start of their illness (85% v 48%; P = 0.001), continue to have more than five coughing episodes a day (P = 0.049), and cause sleep disturbance for their parents (P = 0.003).
Conclusions For school age children presenting to primary care with a cough lasting two weeks or more, a diagnosis of whooping cough should be considered even if the child has been immunised. Making a secure diagnosis of whooping cough may prevent inappropriate investigations and treatment.
Contributors AH, RM-W, and DM obtained funding for the programme of research. AH was principal investigator throughout the study. AH and CG wrote the protocol. TH provided the serology, and TH and ABB gave microbiological advice. RP did the data analysis, supervised by AH and RM-W. AH wrote the manuscript, and all authors commented on the text. AH is the guarantor.
Funding The research was funded by the Medical Research Council as part of a programme grant in childhood infection in primary care (G0000340).
Competing interests None declared.
Ethical approval Oxfordshire research ethics committee (C00.180).