The burden of infectious intestinal disease (IID) in the community: a survey of self-reported IID in The Netherlands

In 2009, a 1-year retrospective survey was performed in The Netherlands to estimate the incidence and the disease burden of infectious intestinal disease (IID) in the community, to study the selection of patients consulting a general practitioner and to identify potential risk factors for IID in the community. A questionnaire was sent to 6000 persons selected at random from the population registries of 28 municipalities, with 500 persons being approached per month. A total of 1975 (33%) persons participated. The incidence rate of IID was 964/1000 person-years. Potential risk factors associated with IID in the community were young age (0-4 years) [odds ratio (OR) 3.9, 95% confidence interval (CI) 1.5-10.5], having asthma as a child (OR 3.4, 95% CI 1.1-10.3) and use of gastric acid suppressive medication by persons aged >= 45 years (OR 2.8, 95% CI 1.4-5.6). Of the 146 cases with IID, 11 (8%) consulted a physician. Cases with a long duration of symptoms, blood in the stool, children with IID and cases with a low level of education were more likely to consult a physician. Two cases had a stool sample taken and one was admitted to hospital. In conclusion, IID is common and has a significant burden of illness in The Netherlands. Our data indicate that about 15.9 million episodes of IID occur in The Netherlands per year. The incidence rate is substantially higher than the rate of 283/1000 person-years as estimated in 1999 in The Netherlands. This is probably largely due to the retrospective nature of the present study and, to a lesser extent, to differences in case definitions.