Dog dust may benefit infant immune systems

Dogs that bring outdoor dust into the house might actually be doing a favor for babies in the home. Research suggests that exposure to doggy dust imparts immune protection to infants. A study of mice shows that the benefits derive from microbes in the dust that enter the intestines and improve the microbial mix, steering the immune system toward fighting disease and away from initiating allergic reactions.

The findings present a microbial twist in the hygiene hypothesis, which argues that a less-than-sanitary early life may prime a child’s immune system against overreacting to grass, dust mites and other ordinary substances. Past studies suggested that babies exposed to multiple siblings, daycare, pets or farm living grow up to have less asthma or allergy.