Environment and Demographic Risk Factors for Egg Allergy

Egg allergies are one of the most common food allergies among young children.  A recent study of about five thousand infants in Australia looked at the incidence of egg allergies at twelve months of age.

Research Question: 

What are the common factors in egg allergic infants?

Findings: 

Families enrolled in the study were asked to complete a questionnaire about their child’s eating habits and reactions to eggs.  Allergy skin testing was also performed on the children.

Out of 5276 children surveyed, 873 were skin test positive to egg white.  699 underwent an egg challenge (given egg to eat in the doctor’s office to see if they had symptoms of an allergic reaction). This would help to determine who exactly had an egg allergy. 

453 of these children had confirmed egg allergy (8.6% of all children in the survey).

Researchers then looked for factors that the egg allergic children had in common.

Results:

Children were less likely to have an egg allergy at one year of age if they had older siblings and if there was a dog in the house.

Children were more likely to have an egg allergy if someone in their immediate family (parent or sibling) had allergies.

Children whose parent or parents were born in East Asia were most likely to have an egg allergy.  Although the parents themselves are less likely to have allergies, their children are more likely to have eczema and egg allergy.

Conclusion: 

Children who live with a dog and who have older siblings have a lower chance of developing egg allergy. Living with pets and older children may expose a baby to viruses and bacteria that help develop a healthy immune system. 

The childhood environment of a baby’s parents may also play a role in the child’s immune system.  In this study, children whose parents were born in East Asia were at highest risk of having an egg allergy.

Environmental and demographic risk factors for egg allergy in a population-based study of infants. Koplin JJ, Dharmage SC, Ponsonby AL, Tang ML, Lowe AJ, Gurrin LC, Osborne NJ, Martin PE, Robinson MN, Wake M, Hill DJ, Allen KJ; HealthNuts Investigators.Allergy. 2012 Nov;67(11):1415-22. doi: 10.1111/all.12015. Epub 2012 Sep 7.