Life‐course of atopy and allergy‐related disease events in tropical sub‐Saharan Africa: A birth cohort study
Atopy (defined by elevated allergen‐specific immunoglobulin E [asIgE] or skin prick test [SPT] positivity to common allergens) is associated with ARDs in high‐income countries (HICs) 5, but a heterogeneous picture is described in LMICs 5, suggesting coexistence of atopic and non‐atopic ARD 7.
In HICs, eczema is usually the first presentation in the sequential manifestation of ARDs, and often lessens by age 4 years, when asthma and/or allergic rhinitis emerge, a transition known as the ‘Atopic [or Allergic] March’ 1. Early atopic sensitization is linked to the subsequent development of ARDs 8. However, little is known about the life‐course of ARDs in low‐income tropical environments, which differ from HICs in many aspects of lifestyle and the intensity of exposure to infections, especially chronic parasitic infections.
The Entebbe Mother and Baby Study (EMaBS) is a birth cohort, initially designed to investigate whether anthelminthic treatment in pregnancy and early childhood influences children's response to vaccines and infections 9. Helminths and anthelminthic treatment showed only modest effects on infants’ response to vaccines 10, but hookworm infection in pregnancy was inversely associated with childhood eczema 12, and anthelminthic treatment in pregnancy increased the incidence of infantile 13 and childhood eczema 14. We describe the prevalence, phenotype, severity, inter‐relationships and life‐course of ARD events among children in this tropical birth cohort, to age 9 years.