arasitic infections and other diseases usually associated with the developing world are cropping up with alarming frequency among U.S. poor, especially in states along the U.S.-Mexico border, the rural South and in Appalachia, according to researchers.
Government and private researchers are just beginning to assess the toll of the infections, which are a significant cause of heart disease, seizures and congenital birth defects among black and Hispanic populations.
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The insect-borne diseases -- among them, Chagas and dengue fever -- thrive in shanty towns along the Mexican border, where many homes have no window screens and where poor drainage allows standing puddles for bugs to breed. Outbreaks of a bacterial infection transmitted in rat urine have cropped up among the urban poor in Baltimore and Detroit.
Such parasites as toxocara -- shed in animal feces -- thrive in the soil and sandpits where poor children often play. There are an estimated 10,000 toxocara infections a year in the U.S. Symptoms include wheezing, fever and retinal scarring severe enough to blind. These diseases share a common thread. "People who live in the suburbs are at very low risk," Dr. Hotez said. But for the 37 million people in the U.S. who live below the poverty line, he said, "There is real suffering."
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