Exposure to Other Children Linked to Asthma

Children who attend day care or have many siblings may have a lower risk of developing seasonal allergies, but an increased risk of developing asthma, according to the findings of a recent European research study. The new findings are based on interviews with over 18,000 adults between the ages of 22-44, from 36 countries, including the U.S., New Zealand, Australia, and Europe. The researchers concluded that children who were in day care or had numerous siblings were less likely to develop seasonal allergies or hay fever when they got older, even if their parents suffered from seasonal allergies and hay fever. The risk for allergies also declined the more siblings a child had. However, the report also indicates that children with two or more siblings were more likely to have asthma when adults, and children enrolled in day care before age 5 were also more likely to have symptoms of asthma, such as wheezing. The results may be attributed to the fact that exposure to other children and other germs sets up immunity to possible allergens, but increases the exposure to infections of the lower airways and the lungs, leading to asthma, the researchers concluded.