Risk factors for respiratory infections among children attending day care centres.

Background: Upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI) and acute otitis media (AOM) are common in children attending day care centres.

Objective: This study aimed to characterize the risk factors of URTI, LRTI and AOM in children attending day care.

Methods: A cross-sectional study was conducted in children aged up to 3 years (n = 152) of six day care centres in Porto. Logistic regression was used on independent variables: mother-related, household-related, child-related and day care-related risk factors as predictors of the dependent variables: URTI, LRTI and AOM.

Results: The risk of URTI increased as the number of children decreased [odds ratio (OR) = 0.620, 95% CI = 0.411-0.935], as the area per child decreased (OR = 0.434, 95% CI = 0.206-0.914) and as the disinfection of WC/diapers-change increased (OR = 2.56, 95% CI = 1.089-6.017). There was a higher risk of URTI if nasal aspirators (OR = 6.763, 95% CI = 1.022-44.753), rather than physiologic serum (OR = 5.296, 95% CI = 1.097-25.559), were used at day care centres. The risk of LRTI increased as the household size decreased (OR = 0.213, 95% CI = 0.048-0.937) and it was higher if the child had no siblings (OR = 7.831, 95% CI = 1.065-57.578). The risk of LRTI was higher if the child was not exclusively breastfed (OR = 24.612, 95% CI = 1.108-546.530) and the risk increased as the duration of exclusive breastfeeding decreased (OR = 0.396, 95% CI = 0.170-0.920). The risk of AOM increased as the birth body mass index (OR = 2.247, 95% CI = 1.011-4.992) and weight (OR = 1.607, 95% CI = 1.014-2.545) increased and if nasal aspirators were used (OR = 6.763, 95% CI = 1.022-44.753).

Conclusions: URTI were related with day care centres' risk factors, LRTI were associated with mother-related and household-related risk factors and AOM was connected with child-related risk factors.