[1] St Marys Hosp, David Hide Asthma & Allergy Res Ctr, Newport PO30 5TG, Wight, England
[2] Univ Southampton, Fac Med, Clin & Expt Sci, Southampton, Hants, England
[3] Univ Memphis, Div Epidemiol Biostat & Environm Hlth, Sch Publ Hlth, Memphis, TN 38152 USA
[4] Michigan State Univ, Dept Large Anim Clin Sci, E Lansing, MI 48824 USA
[5] Univ Colorado, Sect Allergy & Immunol, Children Hosp Colorado, Denver, CO 80202 USA
[6] Univ Southampton, Fac Med, Human Dev & Hlth, Southampton, Hants, England