Science Confirms That Growing Up With A Dog Makes Kids Healthier

Researchers from Finland's National Institute for Health and Welfare, known as THL, have published a study confirming that children who grow up in homes with dogs experience fewer respiratory tract infections during their first year of life and need fewer courses of antibiotics, and for the first time the research has identified a specific biological mechanism explaining why. The study, published in the journal Pediatric Allergy and Immunology and carried out in collaboration with Kuopio University Hospital and the University of Eastern Finland, followed nearly 400 Finnish families and found that the protective effect comes not from the general richness or diversity of bacteria in a dog-owning household, which is higher than in dog-free homes, but from specific microbes that dogs carry with them. When those particular dog-associated bacteria were present in the home environment, children had fewer weeks of illness, fewer weeks of fever, and significantly lower antibiotic use during their crucial first year of development. Three correlated bacterial genera together explained 25 percent of the reduction in antibiotic use, and the strongest protective effect was observed for a bacterium called Pasteurella in relation to fever weeks.

The finding builds on a body of evidence that has been growing for decades, with earlier Finnish studies from the same cohort already establishing that dog-owning families have children with healthier immune profiles, but this study goes further by tracing a specific microbial pathway between the dog and the child's health outcome. Chief researcher Anne Karvonen noted that preventing some early respiratory tract infections through dog-associated microbes may also reduce the child's long-term risk of developing asthma, since early respiratory infections are one of the recognized risk factors for asthma development later in childhood. The greatest health benefits were seen when a dog joined the family during pregnancy or while children were still very young, according to pediatrician and researcher Jenni Mäki, a finding consistent with the understanding that the microbial environment during the first months of life plays a particularly significant role in shaping immune development. The association held even after accounting for family size, living environment, exposure to tobacco smoke, and whether the family lived on a farm, in a rural area, or in a town, and the study's authors said the results support broader public health interest in understanding how everyday animal contact shapes early childhood immunity.

Source:https://yle.fi/a/74-20235109