Kate Hagan September 12, 2012
Participants of a recent study conducted by the Murdoch Children’s Research Institute, Zane Slater, 4, and his sister Jaya, 7, both suffer from food allergies. Photo: Joe Armao
HAVING siblings and a pet dog that comes inside the home can protect infants from developing egg allergies by age one, new research has shown.
In a study of 5000 Victorian infants, researchers from the Murdoch Children's Research Institute found that 10.2 per cent of those without a pet dog had egg allergies, compared with only 5.9 per cent of those who did.
Siblings also had a significant effect, with the incidence of egg allergies in infants decreasing with the number of brothers and sisters they had.
A total of 10.8 per cent of infants with no siblings had egg allergies, which affected just 3.7 per cent of infants with three or more siblings.
Egg allergy was the most common food allergy, affecting one in 10 children in the study. Children with an egg allergy usually outgrow it but are at increased risk of other allergic diseases including asthma.
Lead researcher Jennifer Koplin said young siblings and dogs might have a protective effect by exposing infants to infections and germs, which were thought to be important in training their immune systems to respond appropriately to threats.
''If the immune system doesn't get this exposure, we think it responds inappropriately to things that are completely harmless, in this case foods,'' she said.
Dr Koplin said the study, published in journal Allergy, provided support for the theory that food allergies were more prevalent than in the past due to increasing hygiene, in combination with genetic factors.
Among the participants in the study was Zane Slater, 4, who is allergic to egg white, sesame and peanuts. His sister Jaya, 7, also has allergies to egg, sesame and nuts.
Mum Suba Slater said Zane attended a ''nut-free'' kindergarten and understood that he could not eat certain foods - including birthday cake.