Since 2001, the government has spent almost $50 billion for national biodefense at sites such as Fort Detrick and other specialty laboratories and universities, and this amount is likely to increase further with ambitious plans to build high-containment laboratories across the country. To be sure, there is an excellent rationale for improving our defense against biological threats. But the diseases that we are preparing against do not currently exist in our country. There is no inhalational anthrax, smallpox or bird flu, and it is unclear whether we are likely to face such biological threats any time soon.

However, there is a largely unaddressed biological threat that does exist in America today - especially in places where poverty is concentrated, such as Baltimore. It is a hidden underbelly of poverty-related diseases that are ordinarily thought of as health problems in less-developed countries. The mainly Hispanic and African-American populations living in inner cities and rural areas are suffering from high rates of these ailments, known as the "neglected infections of poverty."

That these diseases exist in large numbers in the world's most prosperous nation is reason for shame and alarm - and action.

Neglected infections of poverty are so named because they affect the voiceless poor and because they actually cause poverty by impairing child development and memory, causing bad pregnancy outcomes and harming worker productivity. For instance, cysticercosis - a brain infection caused by a tapeworm parasite - occurs in an estimated 169,000 Hispanics in whom it is now a leading cause of epilepsy and seizures. Hundreds of thousands of Hispanics living in poverty in the U.S. are also at risk from acquiring Chagas disease, a cause of heart failure that results from infection with a protozoan parasite transmitted by the bite of assassin bugs resembling large cockroaches.

But these are not immigrant diseases. Baltimore, for example, is far from immune to these debilitating conditions. Since the 1990s, it has been known that leptospirosis is transmitted among residents of Baltimore who are exposed to rat urine. (A study published in 1992 found that 16 percent of black males at an STD clinic tested positive for leptospirosis, which can cause a debilitating illness called Weil's disease.)

Up to 2.8 million African-Americans, mostly children, living in inner cities in the Mid-Atlantic and the South are infected with the roundworm Toxocara parasite that has been linked to asthma. And compared with white women, young black women have up to a fiftyfold greater risk of acquiring cytomegalovirus (CMV) during their pregnancy and then passing it onto their unborn babies. The resulting congenital CMV infection is a major reason why babies are born with mental retardation and deafness.

High rates of the parasitic infection trichomoniasis have also been seen in Baltimore; one study found a rate of 8.6 percent among the city's female intravenous drug users. Another study, with a larger sample size, found the disease in 97 of 337 women, a rate of 29 percent.

The high burden of neglected infections among African-Americans builds on another recent finding by the Black AIDS Institute: that rates of HIV among blacks living in the U.S. are as high as in some African countries. Together, the neglected infections and HIV/AIDS represent an important reason why minorities often cannot escape poverty.

The American public would not tolerate it if children in wealthy suburbs were subjected to these diseases. There would be a national outcry for increased measures to learn more about neglected infections and how we could prevent and treat them. Instead, because they occur almost exclusively among the poorest people in our society, most of whom are people of color, they have become forgotten diseases among forgotten people.

Both major presidential candidates are working to establish robust policies for health care reform that include increasing access, lowering costs and improving quality. We also need a national dialogue about these neglected infections that makes cysticercosis, Chagas disease, toxocariasis and congenital CMV infection household words.

Expanded national efforts are needed to determine the full extent of these neglected infections and then to find ways to prevent them, either with existing methods or by developing new drugs, diagnostics and vaccines. This initiative should involve the Centers for Disease Control and Prevention, the National Institutes of Health and major academic institutions such as the Johns Hopkins Bloomberg School of Public Health.

We need to take measures - soon - to eliminate this most glaring of health disparities.

Dr. Peter Hotez is president of the Sabin Vaccine Institute and Walter G. Ross professor and chair of microbiology, immunology and tropical medicine at George Washington University. His e-mail is mtmpjh@gwumc.edu.