KEY POINTS FROM THIS ARTICLE: 1) This is the first study that has evaluated the significance of pet contacts duringchildhood for the development of respiratory tract infections. The object of this studywas to investigate the effect of dog and cat contacts on the frequency of respiratorysymptoms and infections during the first year of life. This study is a prospective cohortstudy of 397 children on respiratory tract infections and animal exposures during thefirst year of life. 2) Assessed co-variables included birth month, birth weight, number of older siblings,maternal smoking, parental atopy (asthma, allergic eczema, or rhinitis), paternaleducational levels, and breast-feeding status. 3) Viral respiratory infections are frequent, occurring between 3 and 6 episodesduring the first of year life. 4) Children having dogs at home were healthier (had fewer respiratory tractsymptoms or infections) than children with no dog contacts, by 31%. 5) Children having dog contacts at home had less frequent otitis [by 44%] andtended to need fewer courses of antibiotics [by 29%] than children without suchcontacts. 6) Both the weekly amount of contact with dogs and cats and the average yearlyamount of contact were associated with decreased respiratory infectious. 7) Dog contacts may have a protective effect on respiratory tract infections duringthe first year of life. 8) During the first year of life, animal contacts are important, possibly leading tobetter resistance to infectious respiratory illnesses during childhood. 9) Breast-feeding reduces the risk of infant respiratory infections. 10) Parent smoking increases the risk of infant respiratoryinfections. 11) If children had dog or cat contacts at home, they were significantly healthierduring the study period. These children had fewer weeks with cough, otitis, and rhinitisand also needed fewer courses of antibiotics than children with no cat or dog contacts at all.