HELMINTH INFECTION AND ALLERGIC SENSITIZATION IN ESWATI CHILDREN

Abstract

Introduction The link between helminth infection and allergic conditions is complex and the two conditions have been noted to be both indirectly and directly related. Here we describe helminth infection, allergic symptoms, environmental exposures, and allergen sensitization among patients at a clinic in Mbabane, Swaziland. Methods Participants are enrolled in a longitudinal umbrella study which houses the nested case control study presented here. Allergic symptoms are defined by clinician H&P, and interviewer-guided modified International Survey on Allergies and Asthma in Childhood survey in Siswati. Environmental exposures were identified using interviewer-guided survey in Siswati. IgE sensitization to more than 160 allergen molecules was detected using ImmunoCAP ISAC technology. Results On average patients were 8 years old and 44% were male. Nineteen percent (38/188) of participants have current helminth infection and 8% (15/188) have remote helminth infection. Sixty-eight percent (128/188) of participants surveyed were positive for one or more allergic symptom. Eczema/rash was more prevalent in children with exposure to a miner in the home. Remotely infected patients had less allergy symptoms. House dust mite allergens were the most common allergens recognized in this population 28% (45/160). Allergen sensitization was strikingly absent or low in patients with helminth infection. Conclusions Our evidence suggests that allergic symptoms are common in this population and allergies are less likely among patients with remote helminth infection. There is a dampening of allergen sensitization in patients with helminth infection and allergy symptoms in patients with remote helminth infection. These results support the hygiene hypothesis, in part, and further elucidate its complexities.