Tropical diseases usually common in Africa, Asia and Latin American appear to be also common among the poor in the United States, according to a report published by the Public library of Science’s journal Neglected Tropical Diseases.

About 36 million people in the U.S. live below the poverty line, thus increasing their risk of contracting tropical diseases. These people are located in the Mississippi Delta, Appalachia, inner cities, and Mexican borderlands.

Lead author of the report Peter Hotez of the Global Network for Neglected Tropical Diseases, part of Sabin Vaccine Institute says the diseases are caused by chronic viral, bacterial and parasitic infections, leaving thousands of people suffering complications such as mental retardation, heart disease and epilepsy, Reuters reports.

The most common diseases include Chagas, spread by blood-sucking insects; cysticercosis, spread by tapeworm eggs in dirty drinking water and worm diseases usually spread by pets living near soil houses and have not been dewormed. Other infections spread by pets are toxoplasmosis, an infection resulting from exposure to parasites carried by cats and toxocariasis, a parasite transmitted in dog droppings.

Dengue fever, carried by mosquitoes is also common among the U.S. poor. The disease can cause a deadly hemorrhagic fever. Cysticercosis, a parasitic worm infection is now considered the leading cause of epilepsy among Hispanics, the report found.

Strongyloidiasis, caused by a threadworm that lives throughout the body, infects 68,000 to 100,000 people. One threat to babies is cytomegalovirus, which infects 27,002 newborn annually causing deafness and mental retardation. Syphilis and trichomoniasis constitute other reasons of concern among the poor.

Dr. Hotez said the statistics are the more shocking as the U.S. is spending $1 billion a year preparing for outbreaks of diseases that have not occurred, including smallpox, anthrax, and avian influenza. Moreover, he considers the rising of these tropical diseases an “unintended form of racism” as they “are occurring among voiceless people,” to which authorities pay little attention.