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From Weina, Neafie, Wortmann, Polhemus and Aronson, "Old World Leishmaniasis: An Emerging Infection among Deployed US Military and Civilian Workers", Clinical Infectious Diseases 39:1674-1680, 2004:
Many veterans of Operation Iraqi Freedom are now returning to the United States after potential exposure to leishmaniasis. In the past year, large numbers of leishmaniasis cases of a magnitude not encountered in the United States since World War II have challenged clinicians in both the military and the civilian sectors. Many Reserve and National Guard troops were deployed to Iraq and are now back in their communities. Hundreds of leishmaniasis cases, which were managed by a few practitioners initially, permitted further appreciation of the epidemiology and diagnostic and treatment options for Old World leishmaniasis. We describe the current situation, with on-the-ground experience, complimented by a literature review, and we provide a practical list of options for the clinician likely to encounter this parasitic infection in the coming months and years.
In the past year, there were >600 cases of cutaneous leishmaniasis and 4 cases of visceral leishmaniasis diagnosed in American soldiers deployed to Iraq, Kuwait, and Afghanistan <1>. Leishmaniasis is a sandfly-borne parasitic disease caused by protozoa that live inside macrophages in mammals. Sandflies become infected after feeding on the reservoir animal (rodents, dogs, and other small mammals) or infected humans and can then transmit the parasite to other humans. Leishmaniasis is characterized by diverse clinical manifestations ranging from asymptomatic infections to self-limited cutaneous disease to life-threatening visceral disease. There are 3 major clinical syndromes: visceral disease (in which the parasite replicates throughout the reticuloendothelial system), cutaneous disease (in which it replicates in the dermis), and mucosal disease (in which it involves in the naso-oropharyngeal mucosa).
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Old World visceral disease is associated with Leishmania infantum and Leishmania donovani. Visceral leishmaniasis usually begins in the absence of any recognizable skin lesion or scar. The symptoms are nonspecific and include some or all of the following: irregular high fever, cough, weight loss, anemia or pancytopenia, hepatosplenomegaly, lymphadenopathy, and fatigue. In untreated adults, especially in those who are protein malnourished or coinfected with other pathogens (e.g., HIV), and in young children, visceral leishmaniasis can be fatal.
In Operation Iraqi Freedom, US soldiers had intense vector exposures and often reported receiving hundreds of insect bites starting in late April 2003. Over 50,000 sandflies were collected from 14 sites in Iraq. Infection rates in sand flies, which were determined using batch PCR testing, ranged from 0.06% to 2.78% <4>. Of 310 patients with leishmaniasis who were interviewed at the Leishmaniasis Treatment Center of Walter Reed Army Medical Center (Washington, DC), 80% had used topical repellents, but 26% noted that these were unavailable at some times during their deployment, 17% had ever treated their uniforms with permethrin, and 10% slept under a bednet.
From Zapor and Moran, "Infectious diseases during wartime", Current Opinion in Infectious Diseases 18:395-399, 2005:
During the period August 2002–February 2004, cutaneous leishmaniasis was diagnosed in 522 military personnel serving in Afghanistan, Iraq or Kuwait and evaluated at the WRAMC <1•>. In each case, the diagnosis was confirmed by microscopy, culture and/or polymerase chain reaction (PCR). Isoenzyme electrophoresis of cultured parasites provided speciation in 176 cases and, in each case, Leishmania major was the etiologic organism. The actual number of confirmed cases in Army personnel is now approximately 827. Presumably, there are many more undiagnosed cases. In their review of the subject, our colleagues Weina et al. <2••> provide demographic information about the cases of cutaneous leishmaniasis among US and coalition soldiers serving in OIF. Most cases occurred among Army troops and most lesions appeared between August and November 2003 (nearly one-half of which occurred between September and October). In the same article, Weina et al. <2••> describe the methods employed for diagnosis (identification of amastigotes in Giemsa-stained skin scrapings, parasite culture and PCR using a genus-specific probe developed at the Walter Reed Army Institute of Research). Weina et al. <2••> also review the treatment modalities, including cryotherapy, thermosurgery, topical S-nitroso-N-acetylpenicillamine, topical paromomycin, oral azoles and the pentavalent antimonies. The latter are administered in the USA under investigational new drug protocols held by the Centers for Disease Control and the Army Surgeon General. Of note, the number of newly diagnosed cases of cutaneous leishmaniasis evaluated at the WRAMC is waning significantly. The reasons for this are multi-factorial and probably include better shelters for OIF soldiers, command emphasis on the use of insect repellents and a change in Department of Defense policy that now permits treatment with oral azoles or the ThermoMed device in the theater of operations with intravenous pentavalent antimony reserved for refractory cases. Cutaneous leishmaniasis is also endemic to Afghanistan and has been diagnosed in soldiers participating in OEF. In a survey of 16 Afghan refugee camps, Kolaczinski et al. <3> found the prevalence of active leishmania lesions and scars to be 2.7 and 2.4%, respectively. In a subsequent paper, Brooker et al. <4> report that the prevalence of cutaneous leishmaniasis in northwest Pakistan is similar in both Afghan refugees and Pakistanis. Although L. major is the most commonly identified species in soldiers evacuated to WRAMC, other species are also endemic to the theaters of operation. To date, four confirmed cases of visceral leishmaniasis (kala azar) have been diagnosed in OEF soldiers treated at the WRAMC, and at least one elsewhere <5>. In these cases, PCR amplification implicated species belonging to the Leishmania infantum–donovani complex. Unlike the benign, generally self-limiting manifestations of cutaneous leishmaniasis, visceral leishmaniasis has a more fulminant presentation and may be mistaken for lymphoma. In one representative report, our colleagues and others describe the cases of two Special Forces soldiers serving in Afghanistan who presented with fever, cachexia, hepatosplenomegaly, pancytopenia, hyper--globulinemia and hypoalbuminemia <6•>. In both cases, visceral leishmaniasis was diagnosed by the demonstration of amastigotes in liver biopsy specimens. Both patients were treated with a lipid formulation of amphotericin B. However, one patient relapsed and was subsequently treated with sodium stibogluconate, a pentavalent antimony compound. For an update of cutaneous leishmaniasis in the returning traveler, see the review by Magill <7••>. For a review of current cutaneous and visceral leishmaniasis treatment modalities, see the review by Berman <8••>.
Leishmaniasis sounds nasty and the US doctors are not used to seeing it. Unfortunately, it's one of many diseases popping up.
I'm not a doctor, but I play one on the internet.
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