Dogs are no longer just man's best friend - the furry family members may also protect infants against breathing problems and infections, according to a European study.
Researchers, whose report appeared in the journal Pediatrics, found that Finnish babies who lived with a dog - or, to a lesser extent, a cat - spent fewer weeks with ear infections, coughs or runny noses. They were also less likely to need antibiotics than infants in pet-free homes.
"These results suggest that dog contacts may have a protective effect on respiratory tract infections during the first year of life," wrote lead author Eija Bergroth, at Kuopio University Hospital in Finland, and colleagues.
"Our findings support the theory that during the first year of life, animal contacts are important, possibly leading to better resistance to infectious respiratory illnesses during childhood."
The researchers studied 397 infants who were born at their hospital between September 2002 and May 2005 for their first year. Parents filled out weekly diaries starting when the child was nine weeks old, recording information on the babies' health as well as their contact with cats and dogs.
Based on those diaries and a year-end questionnaire, the researchers determined that 35 per cent of the children spent the majority of their first year with a pet dog and 24 per cent in a home with a cat.
Before their first birthday, 285 of the babies had at least one fever, 157 had an ear infection, 335 had a cough, 128 wheezed, 284 got stuffy or runny noses and 189 needed to take antibiotics at some point, parents reported.
The researchers found that contact with dogs, more than cats, was tied to fewer weeks of sickness for babies.
For example, infants with no dog contact at home were healthy for 65 per cent of parents' weekly diary reports. That compared to between 72 and 76 per cent for those who had a dog at home.
Babies in dog-owning families were also 44 per cent less likely to get inner ear infections and 29 per cent less likely to need antibiotics.
Infants who spent more than zero but fewer than six hours per day at home with a dog were the least likely to get sick, the researchers said.
"A possible explanation for this interesting finding might be that the amount of dirt brought inside the home by dogs could be higher in these families because (the dog) spent more time outdoors," the researchers wrote.
Bergroth told Reuters Health in an email that the dirt and germs a dog brings into the house may cause a child's immune system to mature faster, which makes it better at defending against viruses and bacteria that cause respiratory problems.
Experts said that while not all research agrees that exposure to dogs and cats helps protect children against breathing problems, there is an overall trend in that direction.
Bergroth also warned that the research couldn't rule out the possibility that people who owned dogs were less likely to get sick for another reason, and not due to protection offered by pets.