[Prevalence rates of recent illnesses in Danish children, 1994 and 2000]

This study aims to describe the prevalence, types and seasonal variation of recent illnesses in Danish children in 1994 and 2000, and to identify their determinants.

Participants in the Danish Health and Morbidity Survey, 1994 and 2000, were interviewed about the illnesses during the previous 14 days of the children under age 16 living at home. Answers were given for 2,136 children in 1994 and 7,670 in 2000. The data were weighted to provide a nationally representative sample. The illnesses were grouped into ten categories. Logistic regression analysis was used to identify determinants.

The prevalence rate for recent illness did not differ significantly between 1994 and 2000 (13.4-14.0%), but for fever and influenza it increased from 1994 to 2000 (from 1.9% to 3.0%), and in boys from 1 to 2 years of age the total illness rate increased significantly (from 26.7% to 31.9%). Attendance at day care increased the prevalence of recent illness in those 0-2 years old. In 2000, the age-specific prevalence rates were: 0 years: 21.2%, 1-2 years: 29.0%, 3-5 years: 15.7%, 6-8 years: 9.3%, 9-12 years: 9.3% and 13-15 years: 11.5%. The prevalence rates were highest in the January-March quarter: 18.9%. The specific illness rates were: cold/sore throat: 4.5%; fever/influenza: 3.0%; gastrointestinal infection: 1.9%; middle ear infection: 1.3%, lower respiratory infection/asthma: 1.1%; skin disease: 0.6%; conjunctivitis: 0.4%; headache: 0.4%; injury: 0.3%; other: 0.9%.

The rising trend is due in particular to an influenza epidemic in 2000. The high prevalence of infections in 1-to-2-year-olds underscores the need to decrease the spread of infections in day care and to avoid the most vulnerable infants' being cared for along with many other children.