There is a large body of literature evaluating the relationship between early childhood exposure to animals and the risk of asthma, allergies, and respiratory illness. This study, conducted in Finland, focuses specifically on the effect of dog and cat contacts on respiratory tract infections during a child’s first year of life. The authors found a benefit to increased contact with dogs and cats.
Data on almost 400 children were included in the analysis, and the data collection method was particularly strong. The researchers used a prospective study approach—i.e., they identified the participants and then tracked their data going forward, in this case through a weekly diary completed by parents. This approach is superior in most cases to retrospective studies, which rely on personal recall. Researchers also asked the families to fill out questionnaires about additional factors including family size, birth weight, smoking, and family history of respiratory illness.