Bacteria employed to fight parasitic disease.

• Position: Listeria, Leishmaniasis - Brief article

Leishmaniasis is a disease caused by parasites that are transmitted by sand fly bites, and considered one of the most important emerging parasitic diseases--with 2,000,000 new cases annually--second only to malaria in terms of the number of affected people. Iraq and Afghanistan, where the U.S. military is on active duty, are among the 88 nations where this disease is prevalent.

Cutaneous leishmaniasis causes skin ulcers on the face, arms, and legs that, without treatment, leave significant scarring. The conventional drugs used to treat it are highly toxic and expensive--and the parasites are becoming resistant.

Helene Marquis, associate professor of microbiology at Cornell University, Ithaca, N.Y., has been approached by the Department of Defense to develop vaccines that use the bacteria Listeria as a delivery device. "Listeria is primarily known as a food-borne microbe that has the ability to multiply in a large variety of cell...