Does early animal exposure reduce allergy and asthma risk?

Look at any social media app, such as Instagram, and you’ll find plenty of pictures of infants curled up with the family cat or dog. Does this close bond between child and animal play a role in developing asthma or allergy? An investigation in Pediatrics Allergy and Immunology takes a look.¹

Researchers enrolled children who were participating in the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Nutrition Study. When the child was aged 5 years, researchers administered a validated version of the International Study of Asthma and Allergies in Childhood questionnaire to find information on asthma, allergic disease, and exposure to farm animals and indoor pets within the first year. Serum samples were used for allergen‐specific immunoglobulin E antibody analysis.

Among the 3781 participants, investigators found that having a dog in the house was inversely tied to the risk of asthma (hazard ratio 0.60; 95% confidence interval [CI], 0.38‐0.96), allergic rhinitis (odds ratio [OR] 0.72; 95% CI, 0.53‐0.97), and atopic sensitization (OR 0.77; 95% CI, 0.63‐0.96). Houses with cats had a decreased risk of atopic eczema (OR 0.68; 95% CI, 0.51‐0.92). Farm animals, either on their own or in conjunction with house pets, had no association with outcomes.

The investigators concluded that exposure to a dog or cat in the first year of life may provide some protection against both allergy and asthma. They stated that future research would be required to determine specific exposures and whether those exposures could be recommended to prevent allergies.

Reference:

1. Ojwang V, Nwaru B, Takkinen H et al. Early exposure to cats, dogs and farm animals and the risk of childhood asthma and allergy. Pediatric Allergy and Immunology. 2020;31(3):265-272. doi:10.1111/pai.13186