To cite this article: Mullins RJ, Clark S, Katelaris C, Smith V, Solley G, Camargo CA, Jr. Season of birth and childhood food allergy in Australia. Pediatric Allergy Immunology 2011; 22: 583–589.
Background: Recent studies suggest a possible role for low ultraviolet radiation exposure and low vitamin D status as a risk factor for food allergy. We hypothesized that children born in autumn/winter months (less sun exposure) might have higher food allergy rates than those born in spring/summer.
Methods: We compared IgE-mediated food allergy rates by season of birth in 835 children aged 0–4 yr assessed 1995–2009 in a specialist referral clinic, using population births as controls. To address potential concerns about generalizability, we also examined national prescriptions for adrenaline autoinjectors (2007) and infant hypoallergenic formula (2006–2007).
Results: Although live births in the general ACT population showed no seasonal pattern (50% autumn/winter vs. 50% spring/summer), autumn/winter births were more common than spring/summer births among food allergy patients (57% vs. 43%; p < 0.001). The same seasonal pattern was observed with peanut (60% vs. 40%; p < 0.001) and egg (58% vs. 42%; p = 0.003). Regional UVR intensity was correlated with relative rate of overall food allergy (β, −1.83; p = 0.05) and peanut allergy (β, −3.27; p = 0.01). National data showed that autumn/winter births also were more common among children prescribed EpiPens (54% vs. 46%; p < 0.001) and infant hypoallergenic formula (54% vs. 46%; p < 0.001).
Conclusions: The significantly higher rates of food allergy in children born autumn/winter (compared to spring/summer), the relationship between relative food allergy rates and monthly UVR, combined with national adrenaline autoinjector and infant hypoallergenic formula prescription data, suggest that ultraviolet light exposure/vitamin D status may be one of many potential factors contributing to childhood food allergy pathogenesis.