It was believed for many years that a child who attended a crèche would be exposed to germs and illnesses more than a child who was cared for in a home, and therefore would build immunity to developing asthma and allergies. A recent landmark study found this to be false.
Children who are exposed to more germs and illnesses will suffer more colds, wheezing, and allergy symptoms early on, but in no way does this build immunity to asthma or allergies in later life.
The study, carried out by Dutch researchers, followed 3,600 children from birth through 8 years of age and found that when children started care in a crèche early they were two times more likely to have illnesses in their first year of life that children cared for at home.
However, the study did show that at the age of 5, these same children had fewer illnesses such as the common cold. So, there may be some merit to the fact that exposure can build an immunity to the common cold; however, by age 8, the study showed that there was no difference in the amounts of asthma and allergies between the two groups.