Risk factors of acute diarrhoea in summer – a nation-wide French case-control study

The aim of this study was to identify risk factors for acute diarrhoea (AD) during the summer in France. A matched case-control study was conducted at a national level among patients of 500 general practitioners (GPs). From July to September 1996, 468 case-control pairs were included. Cases were more likely than controls (i) to live away from their main residence (OR 3·0; 95% CI 1·6–5·7), (ii) to have returned from a country at high risk of AD (OR 4·6; CI 0·9–23·1), and (iii) to have been in contact with a case of AD (OR 2·0; CI 1·3–3·1). A significantly decreased risk of AD was found for consumption of well-cooked chicken (OR 0·5; CI 0·3–0·8) and raw or undercooked home-made egg-containing products (OR 0·6; CI 0·4–0·8). These findings suggest that travel to high-risk areas, or travel within France, and being in contact with a case of AD, are risk factors for the occurrence of AD in summer in France.