An study reported in the Journal of Allergy and Clinical Immunology published in June 2014, titled Effects of early-life exposure to allergens and bacteria on recurrent wheeze and atopy in urban children, followed a group 560 at-risk newborns to see how their exposure during the first year of life to allergens and bacteria correlated with the development of asthma and other allergic symptoms at age three.
“Children free of wheezing and allergies at age 3 had grown up with the highest levels of household allergens and were the most likely to live in houses with the richest array of bacterial species.”
The sum findings: Children exposed during their first year of life to allergens (cat and mouse and cockroach) and certain strains of bacteria were least likely to develop asthma and other allergy symptoms. When the exposure happened later in life (age 3) it did not have the same preventive effect.
A dose of prevention: By the time children turn 3, half of them have wheezing which may go on to become full blown asthma. Maybe its time to get those kiddos playing on the floor and outside in the dirt!