Vaccination and allergy
Allergic conditions, particularly food allergies, have become much more common and more severe in the last 20 years. These conditions arise because the affected child's immune system is over-sensitive, and produces a much stronger response to environmental triggers than would normally be expected. Why this hyper-sensitivity should be occurring in so many more children than in previous generations is not known.
Food and other allergies appear to have increased since the phasing out of the original whooping cough vaccine in the late 1990s. The type of immune response to the two vaccines is markedly different, leading some researchers to propose that the original vaccine may have had a protective effect against developing food and other allergies. We are examining this in two different studies.
In the first study, we will look at the health records of children born in the late 1990s and compare the rate of food allergies in children who were vaccinated with the current whooping cough vaccine with those who received the original vaccine. If there is a lower rate of food allergies in the group that only received the original vaccine, it will provide evidence of a protective effect that we can investigate further.
In the second study, we are testing the theory that one dose of the original vaccine at 6-8 weeks of age may reduce the risk of developing food allergies. This study will compare two groups of babies - one group who will receive the current standard vaccine schedule, and the other who will receive a dose of the original vaccine at 6-8 weeks of age and then the standard vaccination schedule after that. We will examine whether the original vaccine is safe and acceptable to mothers, and if there are fewer cases of allergy in that group.