Description: The leishmaniases are a diverse group of diseases
caused by protozoan parasites of the genus Leishmania that are
transmitted by the bite of infected female sand flies. The
leishmaniases include a wide spectrum of diseases ranging from a
relatively benign, ultimately self-healing cutaneous form (cutaneous
leishmaniasis, CL) to a potentially fatal systemic disease (visceral
leishmaniasis, VL). The cutaneous form of the disease can sometimes
cause highly disfiguring lesions secondary to scar formation or, with
certain species of Leishmania present in the Americas, can spread to
the nose or mouth causing a form of the disease called mucosal
leishmaniasis (ML) that causes disfiguring damage to the face.
Visceral leishmaniasis is the most serious form of the disease and
involves infection of the spleen, liver, bone marrow, and lymph
nodes. Untreated VL is usually fatal.

Symptoms: People with CL have one or more non-healing sores on the
skin, which are typically not responsive to treatment with
antibiotics or steroids. Sores my change in size and appearance over
time and some may heal by themselves. Sores can be painful or
painless. Some people have swollen lymph nodes near the sores.
People who have VL usually have long-term fever, weight-loss, and
sometimes an enlarged spleen or liver. People with VL usually have
elevated liver function tests or low blood counts (low white blood
cell count, low red cell count and/or low platelet count).

Occurrence: An estimated 12 million people in 88 countries on five
continents suffer from the leishmaniases, with an estimated 350
million persons at risk. More than one million new cases of human
leishmaniasis are estimated to occur every year worldwide, but
underreporting of the disease is suspected due to lack of available
screening methods and lack of universal access to up-to-date
diagnostic methods.

Impact on Military Operations: Both CL and VL occurred in thousands
of soldiers in World Wars I and II. In Operation Desert Shield/Storm
(1990-91), there were 20 reported cases of CL and 12 cases of VL.
Since January 2003, over 500 cases of CL and two cases of VL have
been diagnosed among troops deployed to Operations Enduring Freedom
and Iraqi Freedom.

Prevention: There are no U.S. Food and Drug Administration-licensed
prophylactic drugs or vaccines for leishmaniasis. The primary method
of preventing leishmaniasis is to prevent infected sand fly bites.
Methods currently used for the prevention of leishmaniasis include
use of Personnel Protective Measures (PPM), insecticides and animal
control. PPM include the use of topical DEET lotion (an insect
repellent) and the proper wearing of insecticide-treated clothing.
Sand flies can get through standard mosquito nets, so bed nets and
tents need to be permethrin-treated as well.

Current Research Efforts: Funding for the military leishmaniasis
research program was discontinued after FY02. However, the research
did lead to the development of two products, a candidate Leishmania
Skin Test Antigen and a topical formulation of the well-known anti-
leishmanial drug, paromomycin. These products are in clinical trial;
however, resources have not been adequate and FDA licensure of these
products is still several years away. Another drug, Sitamaquine, was
discovered by the U.S. Army. A commercial partner is completing its
development for treatment of VL at no cost to the program. A
clinical trial is currently underway at the Walter Reed Army Medical
Center to evaluate an FDA approved localized current radio frequency
device (ThermoMed™, Thermosurgery Technologies, Inc., Phoenix,
AZ)for treatment of patients with CL.

If funding is obtained, the proposed research efforts for this fiscal
year are directed at development of: (a) a point-of-care (i.e.,
without a laboratory) diagnostic system for use in the area of
operations, (b) a rapid test for Leishmania infection in sand flies
that will provide preventive medicine personnel advance knowledge of
the Leishmania threat in areas of deployment and encampment, and (c)
a device for screening for latent leishmaniasis (infection without
disease) to protect the blood supply.

More Information. Contact COL David W. Vaughn, M.D., M.P.H. at Fort
Detrick, Maryland, (301) 619-7567
email: david.vaughn@....