Letters

Risk factors for winter outbreak of acute diarrhoea in France

BMJ 1998; 317 doi: https://doi.org/10.1136/bmj.317.7151.145 (Published 11 July 1998) Cite this as: BMJ 1998;317:145

Winter outbreaks of diarrhoea occur in United Kingdom too

  1. Tamara Djuretic, Specialist registrar,
  2. Mary E Ramsey, Consultant epidemiologist, immunisation division,
  3. Paddy C Farrington, Deputy head of statistics unit,
  4. Douglas M Fleming, Director,
  5. David Brown, Director
  1. Public Health Laboratory Service Communicable Disease Surveillance Centre, London NW9 5EQ
  2. Royal College of General Practitioners, Birmingham B17 9DB
  3. Enteric and Respiratory Virus Laboratory, Central Public Health Laboratory, London NW9 5EQ
  4. Centre for Applied Public Health Medicine, University of Wales College of Medicine, Gwent Health Authority, Pontypool, Gwent NP4 0YP
  5. Institute of Public Health, Makerere University Medical School, PO Box 7072, Kampala, Uganda
  6. INSERM Unit 444, Institut Fédératif Saint-Antoine de Recherches sur la Santé, Paris, France
  7. Réseau National de Santé Publique, Saint-Maurice, France

    EDITOR—Letrilliart et al conclude that the winter epidemic of diarrhoea in France in 1995-6 was not associated with consumption of tap water or shellfish, that person to person spread was implicated, and that the epidemic was of viral aetiology.1 Despite considerable reservations about the validity of their evidence we agree that the epidemic may have been largely attributable to viral diarrhoea.

    Mean weekly incidence of infectious intestinal disease seen in general practice, by four week period and age group (from Royal College of General Practitioners' weekly return service, 1992-6)

    Winter outbreaks of viral diarrhoea associated with shellfish have been described in the United Kingdom,2 but the French study's failure to show an association may have been because of the methods used. Infection with small round structured virus, the most frequently identified cause of foodborne viral gastroenteritis, induces short term immunity,3 which could produce perverse effects in a study of this design—for example, people who eat oysters frequently might be differentially immune owing to higher exposure to risk inducing an apparent protective effect for frequent consumption. Separate analysis of primary and secondary cases would be more appropriate to test the primary hypothesis that food and water consumed were responsible for the epidemic.

    The descriptive epidemiology and the design of the study are inadequate to explain the hypotheses selected. …

    View Full Text

    Sign in

    Log in through your institution

    Subscribe