“…Individuals exposed to helminthes for a short time often have allergic-like manifestations (Cooper, 2009). Lynch and collaborators (Lynch et al, 1984(Lynch et al, , 1987(Lynch et al, , 1992(Lynch et al, , 1997 have shown that the intensity of helminth transmission determines the effect of helminth infection on allergic reactivity -in high income urban areas where the transmission is low, the allergic reactivity is high whereas in urban and rural areas where people are chronically infected by helminthes, the allergic reactivity is low. Geohelminth parasite with pulmonary larval stages, such as Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale and Strongyloides stercoralis, are found to cause Loeffler's syndrome which is characterized by eosinophilic infiltrate into the lungs after parasitic infection (Loefller, 1959).…”