Allergic disorders are characterized by predominance of Th2 cells, and hypothetically, the the Th1-dependent mechanisms for fighting respiratory infections may be less active.
Previously, it has been reported that allergic children have more numerous and severe respiratory infections than nonallergic ones. This study focused on adult patients and involved 600 subjects in Italy followed for 2 years, 202 of them had allergic rhinitis.
The study showed that adult allergic patients have more numerous and prolonged respiratory infections than nonallergic subjects (P < 0.001).
References: Allergic patients have more numerous and prolonged respiratory infections than nonallergic subjects. Cirillo I, Marseglia G, Klersy C, Ciprandi G. Allergy. 2007 Jun 18.
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