Astma in Children: Can Exposure to Pests and Dust Decrease Odds?

Key Takeaways:

• Exposure to pests and pet allergens in early years may decrease the likelihood of developing asthma, according to a recent study of inner-city children.
• Maintaining clean homes remains crucial as homes with higher levels of harmful bacteria in the dust are linked to child asthma. Significant influences on a child’s asthma risk also include maternal smoking, stress, and depression during pregnancy.
• The findings suggest a possible reconsideration of home allergen reductions as the primary asthma prevention strategy. More focus may be needed on mitigating prenatal smoking and managing maternal stress and depression during pregnancy and infancy.
• There is a definitive link between the home’s microbial diversity and a child’s asthma risk status. Greater diversity of beneficial bacteria in homes was seen in children who remained asthma-free.
• The health habits of mothers, such as smoking during pregnancy or severe stress or depression, increase the likelihood of the child developing asthma by age 7.

Could early exposure to pests and pet allergens, like cockroaches and mice droppings, actually be beneficial for children? A recent study involving inner-city children suggests just this.

“This aligns with similar findings from last year that challenge the traditional thinking,” comments Dr. Kelvin MacDonald, a pediatric lung specialist. “Ironically, a spotless, disinfected home might not be the best safeguard.”

Control Exposure but Keep the Duster

It’s worth noting, however, that if a child has already been diagnosed with asthma, reducing their exposure to these allergens is critical for the management of their respiratory condition. Additionally, research has found high levels of harmful bacteria, including fecal bacteria, in the dust of homes where children developed asthma by age 7.

Significant influences on a child’s asthma risk also include maternal smoking during pregnancy, maternal stress, and depression, according to the study spearheaded by Dr. George O’Connor, a professor of medicine.

Influence on Asthma Prevention Strategies

These findings could lead to a new approach for preventing asthma, a condition that affects more than 8 percent of Americans and often results in emergency room visits and hospital admittances due to bouts of inflammation and narrowing of the airways, causing disruptive wheezing and coughing.

A potential rethink on current prevention strategies: “Our findings invite a reconsideration of home allergen reduction as the primary prevention strategy for childhood asthma in low-income urban communities. A more projective approach may rest in mitigating prenatal smoking as well as maternal stress and depression during pregnancy and infancy,” the authors pointed out.

Investigative Overview

The study, which monitored 560 children from birth to the age of 7 in Baltimore, Boston, New York City and St. Louis, found that children who had higher levels of exposure to certain allergens such as cockroach, mouse and cat during their early years showed a decreased likelihood of developing asthma. A slight association with dog allergens was also noted.

Microbes Matter

Fascinatingly, the study revealed significant connections between home microbial diversity (or “microbiome”) and asthma risk status. The homes of the children who developed asthma tended to have higher levels of harmful bacteria, while homes of children who remained asthma-free had a richer variety of beneficial bacteria.

Dr. James Gern, co-author of the study, noted that pests and pets have a significant impact on a home’s microbiome which, in turn, could contribute to a collective protective effect against asthmatic development in children.

This seemed comparable to how farm children benefit from early exposure to diverse plant and animal allergens, or how suburban kids with dogs at home appear to have fewer allergies and asthma.

“In three distinct environments, we’re deriving a similar narrative,” said Gern.

Mother’s Health and Habits

The study further reinforces existing knowledge about the links between a mother’s health habits and her child’s risk of developing asthma.

Specifically, children whose mothers smoked during pregnancy or experienced severe stress or depression during the child’s early years were more likely to have asthma by age 7. The underlying reasons for this are yet unclear, and researchers insisted that these associations do not automatically imply causality.

More information is available from the American Academy of Allergy, Asthma & Immunology.