Methods: Specific IgE (sIgE) levels were determined to 12 inhalant and food allergens in 659 6-year old children from Wellington (n=316) and Christchurch (n=343) from a birth cohort. Allergens tested were D. pteronyssinus, cat pelt, dog hair, horse hair, cockroach, A. fumigatus, Alternaria, olive pollen, rye grass, egg white, cow's milk and peanut by a 3rd generation liquid chemiluminescent enzyme immunoassay (Siemens IMMULITE 2000). Atopic sensitisation was defined as at least one sIgE ≥ 0.35 kU/L.
Results: Sensitisation was present in 299 children (45.4%). Sensitisation to D. pteronyssinus was most prevalent with 176 children sensitised (26.7%) and with the highest sIgE levels (geometric mean: 9.1 kU/L; 95% CI: 6.2-13.2). The next highest sensitisation rate was to rye grass (141 children, 21.4%) followed by egg white (124 children, 18.8%). Mono-sensitisation was observed in 122 children (18.5%): 44 to egg white, 35 to D. pteronyssinus, 18 to rye grass, 6 to cat pelt, 5 to cow's milk, 4 to peanut, 3 to horse hair, 3 to dog hair, and 1 each to cockroach, A. fumigatus, Alternaria and olive pollen. The other 177 children were poly-sensitised: 60 to two allergens, 40 to three, 26 to four, 22 to five, 17 to six, 3 to seven, 5 to eight, 3 to nine and 1 to all twelve. Of those poly-sensitised the highest sIgE level in three-quarter of these children was to D. pteronyssinus followed by rye grass.
Conclusions: Sensitisation to inhalant and food allergens is high in New Zealand 6-year old children with sensitisation to D. pteronyssinus the most prevalent and with very high sIgE levels.