Dogs & Cats Linked to Healthier Babies

Respiratory and ear infections are lower in infants when they live with dogs and cats

(RxWiki News) When you bring a new baby into the home, what is the impact of the "babies" you already own… the four-legged furry ones who are baffled by this new creature?

According to a new study, owning a dog or a cat - especially a dog - can have a positive impact on the respiratory health of infants, who seem to get fewer respiratory infections and fewer ear infections.

"Living with dogs and cats may help babies stay healthy."

In a study led by Eija Bergroth, MD, of the Department of Pediatrics at Kuopio University Hospital in Finland, researchers investigated what living with dogs and cats might mean for babies in terms of respiratory and ear infections.

The researchers looked at 397 children, born between September 2002 and May 2005 in Finland, starting from their mothers' pregnancy, and they tracked how often the children experienced respiratory infections and symptoms.

They also tracked the babies' contact with dogs and cats during their first year using weekly diaries from the parents and a questionnaire when the children were a year old.

The weekly questionnaires asked whether children had been healthy in the previous seven days and, if not, whether the child had a cough, wheezing, a cold, a fever, an ear infection, diarrhea, a urinary tract infection, an itchy rash or another illness.

The researchers specifically looked at responses regarding fevers and respiratory symptoms like coughing, wheezing and colds as well as ear infections.

They also looked at whether the dogs or cats that lived with children spent more time indoors or outdoors to assess the average contact with the animals for each child. A total of 62 percent of the children lived with a dog, and 34 percent lived with a cat for some period of time during the study.

The researchers found that children who lived with dogs at home were healthier in terms of their respiratory systems and even had fewer ear infections than children not living with dogs. There was similar but weaker evidence for living with cats.

Children who shared their homes with dogs were 1.3 times more likely to have fewer respiratory symptoms and were about half as likely to get ear infections - which meant they used antibiotics less often as well.

Children without a dog at home were healthy about 65 percent of the time according to the weekly questionnaires. Children with a dog inside the home less than six hours a day were healthy 76 percent of the time.

Children with a dog inside from six to 16 hours were healthy 74 percent of the time, and children with a dog inside most of the time (more than 16 hours) were healthy about 72 percent of the time.

The researchers were not sure why the differences occurred regarding how much time the dogs spent indoors or outdoors, but they hypothesized that dogs spending more time outdoors may bring in more dirt.

The additional dirt, with exposure to a greater variety of bacteria, might also contribute to helping kids remain healthier more often as their bodies develop immunities to a broader range of pathogens.

Rates among children with and without exposure to cats were similar. The kids without a cat at home were healthy 66 percent of the time, compared to kids living in proximity to indoor cats, who were healthy 69 to 78 percent of the time. These results were not as strong as the results with dogs, though.

"Cat ownership seemed to also have an overall protective effect, although weaker than dog ownership, on the infectious health of infants," the researchers wrote.

When the researchers took into account the children's gender, birth weight, season when they were born, their number of siblings, whether their mother smoked, whether either parent was allergic to animals, their living environment (rural versus suburban) and whether they were breastfed, the rates remained similar.

The healthiest children after these adjustments were those who had dogs inside often (between six and 16 hours). They were healthy 81 percent of the time compared to the kids without dogs at all, who were healthy 64 percent of the time.

Among cat owners, those with a cat inside temporarily (less than six hours a day) were healthy most often, 82 percent of the time, compared to the kids without cats, who were healthy 66 percent of the time.

Based on background research mentioned in the story, other factors that can lead to increases in respiratory infections among babies include attending daycare, having older siblings (who catch bugs and pass them along), not being breastfed and having a parent who smokes or has asthma.

The study was limited because the researchers did not evaluate the animals separately. Some of the dog owners may have had cats while other families had only a dog or a cat. The study also could not establish that having the animals causes the children to be healthier.

Additionally, it may be that parents who are allergic to animals - and whose children may be more likely to be allergic to dogs or cats - simply choose not to have pets, though the researchers tried to account for this in their calculations.

The study was published July 9 in the journal Pediatrics. The research was funded by the Foundation for Pediatric Research, the Kerttu and Kalle Viikki, Päivikki and Sakari Sohlberg and Juho Vainio Foundations, EVO funding, Farmers’ Social Insurance Institution-Mela, the Academy of Finland and Kuopio University Hospital in Finland. The authors declared no conflicts of interest.

Review Date: 
July 6, 2012