Tungiasis is caused by penetration of the female jigger flea, Tunga penetrans, into the skin of its host. This
parasitic skin disease is almost invariably associated with intense
inflammation around embedded fleas, the underlying mechanisms being unknown. A study was undertaken to determine whether the inflammatory process can be attributed to immune activation induced by a biologically active
foreign body. We determined the concentrations of Th1-mediated (IFN-gamma,
TNF-alpha) and Th2-mediated (IL-4)
cytokines in the sera of patients with
tungiasis. The results were compared with those of controls infected with different helminths or exposed to soil-transmitted helminths. The results show that
tungiasis causes a mixed Th1 and Th2 immune response, characterized by significantly increased concentrations of the pro-inflammatory
cytokines IFN-gamma and
TNF-alpha, with a slightly increased concentration of
IL-4. The preponderance of the Th1 immune response was indicated by a significantly increased
TNF-alpha/IL-4 ratio in patients with
tungiasis, as compared with the control groups.