http://www.allergysa.org/journals/June2014/2014_June_Allergy_SA_Mag_OrgRea2.pdf (http://www.allergysa.org/journals/June2014/2014_June_Allergy_SA_Mag_OrgRea2.pdf)
I added this study as UK currently doesnt give children chicken pox vaccine. Some doctors are trying to get this added to the immunisation list with NHS.