Childhood chickenpox protects against atopic dermatitis
MedWire News: Children who have had chickenpox may be less likely to develop atopic dermatitis than those who have not had the viral infection, say researchers.
They examined the medical records of 256 children and teenagers with atopic dermatitis, a type of eczema that arises from allergic reactions and causes itchy rashes, and 422 similarly aged individuals without atopic dermatitis.
The team looked back in the records to see who had been infected with chickenpox. The results showed that 20% of children who had atopic dermatitis had previously been infected with chickenpox, compared with 28% of children without atopic dermatitis.
Indeed, children previously infected with chickenpox were 45% less likely to have atopic dermatitis than children who had not had chickenpox, but only if they had been infected up to the age of 8 to 10 years. For chickenpox contracted after the age of 10 years there was no association with atopic dermatitis.
Being vaccinated against chickenpox did not protect against atopic dermatitis; vaccinated children were as likely to have atopic dermatitis as uninfected children.
Chickenpox infection, in addition to reducing the risk for atopic dermatitis, chickenpox infection, also delayed the onset of the condition and reduced the severity in those who did develop it.
The team of researchers, led by Jonathan Silverberg, from State University of New York Downstate Medical Center in the USA, say that the effects of a risk for secondary diseases should be considered when determining the cost-effectiveness of vaccination for chickenpox.
"Perhaps delaying vaccination until 8 to 10 years of age would improve long-term outcomes of atopic dermatitis particularly among those who are high risk for developing this condition, without comprising herd immunity," Dr Silverberg told MedWire News.
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By Lucy Piper