Association of deworming with reduced eosinophilia : implications for HIV/AIDS and co-endemic diseases

Abstract

9 /l) decreased from 0.70 in the randomized trial, and 0.61 in the whole-school study, to well within the normal paediatric range of 0.05-0.45 (P < 0.05). The prevalence of eosinophilia declined from 57% to 37% in the randomized trial (mean for 400, 800 and 1200 mg albendazole doses); and from 47% to 24% in the whole-school study (500 mg stat mebendazole). Benzimidazole anthelminthics were highly effective against Ascaris but less so against Trichuris. Activated eosinophils are effector and immuno- regulatory leucocytes of the T-helper cell type 2 (Th2) immune re- sponse to parasitic helminths and atopic disorders. Under conditions of poverty where soil-transmitted helminths are hyperendemic, Th2 polarization of the immune profile is character- istic. Regular anthelminthic treatment should reduce contact with worm antigens, and this may contribute to re-balancing of the immune profile. Suppression of eosinophil recruitment and activa- tion, together with related cellular and molecular immunological changes, might have positive implications for prevention and treatment of co-endemic diseases, including HIV/AIDS, cholera, tuberculosis and atopic disorders.