The threat of infectious disease in Americans returning from Operation Desert Storm

Genetic micro-heterogeneity of Leishmania major in emerging foci of zoonotic cutaneous leishmaniasis in Tunisia

Tunisia is endemic for zoonotic cutaneous leishmaniasis (ZCL), a parasitic disease caused by Leishmania (L.) major. ZCL displays a wide clinical polymorphism, with severe forms present more frequently in emerging foci where naive populations are dominant. In this study, we applied the multi-locus microsatellite typing (MLMT) using ten highly informative and discriminative markers to investigate the genetic structure of 35 Tunisian Leishmania (L.) major isolates collected from patients living in five different foci of Central Tunisia (two old and three emerging foci). Phylogenetic reconstructions based on genetic distances showed that nine of the ten tested loci were homogeneous in all isolates with homozygous alleles, whereas one locus (71AT) had a 58/64-bp bi-allelic profile with an allele linked to emerging foci. Promastigote-stage parasites with the 58-bp allele tend to be more resistant to in vitro complement lysis. These results, which stress the geographical dependence of the genetic micro-heterogeneity, may improve our understanding of the ZCL epidemiology and clinical outcome.

Expression analysis of viscerotropic leishmaniasis gene in Leishmania species by real-time RT-PCR

Viscerotropic leishmaniasis (VTL) is a parasitic disease with non-specific manifestations caused by Leishmania tropica. Specific antigens produced by Viscerotropic leishmaniasis gene have been used for diagnosis of VTL. The aim of this study was to compare the expression level of VTL gene among the viscerotropic L. tropica isolates (n: 3) and visceral L. infantum isolates (n: 4). Also, the expression level was compared in L. tropica (n: 21) and L. major (n: 8) isolates, the main causes of cutaneous leishmaniasis in Iran by real time-RT-PCR. Results showed viscerotropic leishmaniasis gene was expressed in all 3 species; L. tropica, L. major and L. infantum. The most expression rate was in L. tropica and L. major as the cutaneous species and the lowest in visceral isolates including L. infantum and viscerotropic L. tropica strains respectively.

CONCLUSION

Results revealed that VTL gene can play an important role in visceralization process of L. tropica although there are other mechanisms to keep parasite visceralized. According to these primary results, increased the expression level of VTL gene probably could contribute to inhibit the invasive behavior of Leishmania parasites. However, more experimental researches are needed to confirm this idea.

Imaging of pediatric pathology during the Iraq and Afghanistan conflicts

United States Armed Forces radiologists deployed to Afghanistan and Iraq in modern military conflicts may encounter pediatric patients as a casualty of war or when providing humanitarian assistance to the indigenous population. Pediatric patients account for 4-7% of admissions at U.S. military hospitals during the Iraq and Afghanistan conflicts. It is pertinent for radiologists in the humanitarian care team to be familiar with imaging pediatric trauma patients, the pathology endemic to the local population, and delayed presentations of congenital and developmental disorders to adequately care for these patients. The radiological manifestations of various pediatric disorders seen in the setting of the Iraq and Afghanistan conflicts will be explored.

Utility of the microculture method for Leishmania detection in non-invasive samples obtained from a blood bank

In recent years, the role of donor blood has taken an important place in epidemiology of Leishmaniasis. According to the WHO, the numbers of patients considered as symptomatic are only 5-20% of individuals with asymptomatic leishmaniasis. In this study for detection of Leishmania infection in donor blood samples, 343 samples from the Capa Red Crescent Blood Center were obtained and primarily analyzed by microscopic and serological methods. Subsequently, the traditional culture (NNN), Immuno-chromatographic test (ICT) and Polymerase Chain Reaction (PCR) methods were applied to 21 samples which of them were found positive with at least one method. Buffy coat (BC) samples from 343 blood donors were analyzed: 15 (4.3%) were positive by a microculture method (MCM); and 4 (1.1%) by smear. The sera of these 343 samples included 9 (2.6%) determined positive by ELISA and 7 (2%) positive by IFAT. Thus, 21 of (6.1%) the 343 subjects studied by smear, MCM, IFAT and ELISA techniques were identified as positive for leishmaniasis at least one of the techniques and the sensitivity assessed. According to our data, the sensitivity of the methods are identified as MCM (71%), smear (19%), IFAT (33%), ELISA (42%), NNN (4%), PCR (14%) and ICT (4%). Thus, with this study for the first time, the sensitivity of a MCM was examined in blood donors by comparing MCM with the methods used in the diagnosis of leishmaniasis. As a result, MCM was found the most sensitive method for detection of Leishmania parasites in samples obtained from a blood bank. In addition, the presence of Leishmania parasites was detected in donor bloods in Istanbul, a non-endemic region of Turkey, and these results is a vital importance for the health of blood recipients.

Detection of antileishmanial antibodies in blood sampled from blood bank donors in Istanbul

Aims: According to the WHO, only 5–20% of the total cases of leishmaniasis are symptomatic leishmaniasis; the other cases are identified as asymptomatic leishmaniasis. In recent studies, it has been demonstrated that donor blood plays an important role in the epidemiology of asymptomatic leishmaniasis. However, the number of the studies on this subject is still insufficient. Additionally, donor blood samples obtained from Istanbul, which is the biggest metropolitan area in Turkey, have not been investigated with regard to Leishmania. Moreover, there is no information about the sensitivity of noninvasive serological methods that are used in the detection of leishmaniasis donor blood samples. Accordingly, this study aimed to investigate the presence of antileishmanial antibodies in blood samples obtained from blood bank donors in Istanbul, by using different serologic methods, and to determine the most sensitive detection method. Materials & methods: Blood samples were taken from 188 healthy blood bank donors to the Capa Turkish Red Crescent Blood Bank (Istanbul, Turkey), and the presence of antileishmanial antibodies was measured by indirect immunofluorescent antibody test (IFAT), ELISA, immunochromatographic dipstick rapid test, and western blot (WB). Results: Antileishmanial antibodies were determined in 12 out of 188 samples by IFAT (6.4%), and six out of these 12 donors were found to be positive at diagnostic titer 1:128 (3.2%). One hundred and eighty eight samples were investigated by ELISA and one (0.5%) of them gave a positive result. None of 188 samples provided a positive result by immunochromatographic test. WB applied to the 12 seroreactive donors showed that three out of 12 donors were positive. Conclusion: In this study, the presence of antileishmanial antibodies in blood samples of blood bank donors from Istanbul has been demonstrated by using feasible and low-cost serological methods. Additionally, in comparison with other simple and low-cost detection methods, WB was used for confirmation. IFAT has a higher sensitivity and therefore may be preferred as a prescreening method in endemic or nonendemic areas.

Leishmania: risk to the blood supply

Leishmania infection is most often transmitted to humans via the bite of the phlebotomine sandfly, but transmission of Leishmania by transfusion has also been reported. There has been a huge increase in the incidence of cutaneous and visceral leishmaniasis in Iraq and Afghanistan. The deployment of US troops to these countries and published case reports of transmission to soldiers in endemic areas, by transfusion to infants with immature immune systems, and to individuals immunocompromised by disease or immunosuppressive therapy beckon a reexamination of blood donor deferral procedures. The length of the ongoing military conflict and the nature of exposure indicate that prior decisions regarding blood donor deferral made during the first Gulf War may no longer apply. Operation Iraqi Freedom and Operation Enduring Freedom present a much greater Leishmania threat than did Operation Desert Storm. Because most transmission by transfusion occurs in endemic areas, and visceral infection is asymptomatic in healthy individuals such as blood donors, it is difficult to determine the absolute risk of transmission by transfusion, but review of the literature provides many clues as to the appropriate measures to be taken for blood donor deferral.

Impact of phlebotomine sand flies on U.S. Military operations at Tallil Air Base, Iraq: 1. background, military situation, and development of a "Leishmaniasis Control Program"

One of the most significant modern day efforts to prevent and control an arthropod-borne disease during a military deployment occurred when a team of U.S. military entomologists led efforts to characterize, prevent, and control leishmaniasis at Tallil Air Base (TAB), Iraq, during Operation Iraqi Freedom. Soon after arriving at TAB on 22 March 2003, military entomologists determined that 1) high numbers of sand flies were present at TAB, 2) individual soldiers were receiving many sand fly bites in a single night, and 3) Leishmania parasites were present in 1.5% of the female sand flies as determined using a real-time (fluorogenic) Leishmania-generic polymerase chain reaction assay. The rapid determination that leishmaniasis was a specific threat in this area allowed for the establishment of a comprehensive Leishmaniasis Control Program (LCP) over 5 mo before the first case of leishmaniasis was confirmed in a U.S. soldier deployed to Iraq. The LCP had four components: 1) risk assessment, 2) enhancement of use of personal protective measures by all personnel at TAB, 3) vector and reservoir control, and 4) education of military personnel about sand flies and leishmaniasis. The establishment of the LCP at TAB before the onset of any human disease conclusively demonstrated that entomologists can play a critical role during military deployments.

Technology Insight: monoclonal antibody imaging of prostate cancer

Imaging is a critical component of diagnosis, staging and monitoring, all of which factor heavily in treatment decision-making for cancer patients. Agents, such as antibodies, can target molecules that are relatively unique to cancer cells. Prostate-specific membrane antigen (PSMA) is the most well-established, highly restricted prostate-cancer-related cell membrane antigen known. Ten years ago, the FDA approved (111)In-capromab pendetide for use in imaging soft-tissue, but not bone, sites of metastatic prostate cancer for presurgical staging or the evaluation of PSA relapse after local therapy. For presurgical patients with high-risk disease but negative bone, CT and MRI scans, capromab demonstrated the ability to identify some patients with positive nodes, thereby sparing them an unnecessary surgical procedure. But there have been no follow-up studies to indicate that high-risk patients with a negative capromab scan have a lower failure rate after surgery. In the setting of PSA relapse, capromab is compromised by its inability to sensitively image bone metastases; bone is the first site of metastatic prostate cancer in 72% of patients. The problem with imaging bone metastases is that capromab detects an antigenic site on the intracellular portion of PSMA-a site not accessible to circulating antibodies. Early results indicate that second-generation antibodies that target the extracellular domain of PSMA might provide significant benefits in the imaging of prostate cancer.

The surgical pathology and cytopathology of US Persian Gulf War military veterans

BACKGROUND

Tens of thousands of Persian Gulf War veterans (GWVs) have presented with medical symptoms since Operation Desert Shield and Operation Desert Storm. The Kuwait Registry at the Armed Forces Institute of Pathology was established to act as a repository for surgical pathology, cytopathology, and autopsy material from GWVs.

OBJECTIVE

To identify conditions known to be endemic to the theater of operations in our cohort of GWVs.

METHODS

The Kuwait Registry database was searched by computer for listed conditions endemic to the Persian Gulf region included in the registry through December 31, 1997.

RESULTS

Of the 2582 patients in this cohort, 1 patient with hepatitis B and 15 patients with hepatitis C were identified. Other known endemic conditions of the Persian Gulf region were not found.

CONCLUSIONS

Viral hepatitis (B and C), which is prevalent in the US population, was the only listed endemic condition identified in surgical pathology or cytopathology specimens in our cohort of GWVs.

The dermatologist in military operations

The military dermatologist has a specific and significant role in military operations--in time of war as well as in peace. Many dermatologists are unfamiliar with the impact that our specialty and cutaneous disease has upon the ability of the military to fulfill the missions, duties, and responsibilities assigned by our government. This article highlights a few of the recent or ongoing types of military operations in which our specialty plays a prominent part.

Fever in the returned traveler

The most important cause of fever in the returned traveler is malaria. All febrile patients in which malaria is epidemiologically possible require urgent evaluation for P. falciparum malaria, which can be rapidly fatal in the nonimmune patient. Early diagnosis and therapy can prevent severe morbidity and mortality. Other less common causes of undifferentiated fever include acute schistosomiasis, the enteric fevers, rickettsial diseases, leptospirosis, and dengue fever. Early empiric therapy for suspected leptospirosis and the rickettsial infections is encouraged to decrease morbidity and mortality. About a quarter of febrile patients do not have an etiologic agent determined for their illness but recover without sequelae. Patients with fever and hemorrhagic manifestations within 3 weeks of their return need to be isolated for the remote possibility of a highly transmissible agent. Although the febrile traveler is always a challenge, the real world differential diagnosis is limited and a systematic approach via the history, physical examination, and selected laboratory tests is usually sufficient to confirm the diagnosis or eliminate potentially serious infections.

Malaria

The preeminent infectious threat to unwary tropical travelers, malaria is a preventable, mosquito-borne protozoan infection of red blood cells, which causes fever, anemia, respiratory failure, coma, and death. Malaria is a true medical emergency that requires rapid diagnosis and treatment. Unfortunately, in two thirds of tropical travelers who die of malaria, either treatment is delayed or the diagnosis is simply missed. Every tropical traveler with fever or unexplained, flu-like illness must be assumed to have life-threatening malaria and must have thick and thin blood smears immediately examined to confirm the diagnosis.

Health data from Operation Resolute (Bosnia). Part 1: Primary care data

This paper describes routine sickness events occurring during Weeks 1-19 of Operation Resolute (Bosnia). The period covered is 20 December 1995 to 28 April 1996. Primary care data were collected and analysed through an HQ ARRC epidemiological surveillance system which encompassed all British personnel in theatre. There was a total of 17,054 primary care consultations in the British force, which at its peak in late January numbered 10,832 personnel. 11,472 of these consultations were due to disease (67% of the total) and 5568 to non-battle injury (32% of the total). The observed rate of sickness due to disease was close to the predicted rate, which was 1.35% of the force per day. The observed rate of sickness due to non-battle injury was between 6 and 10 times higher than the predicted rate of 0.05% of the force per day. There were only 14 primary care consultations due to battle injury.

Whipple's disease presenting as chronic wastage and abdominal lymphadenopathy

We describe a 24-year-old man who presented with chronic wastage and massive abdominal lymphadenopathy which strongly resembled a malignant neoplasm. Biopsy of mesenteric lymph nodes with ancillary studies led to the correct diagnosis of Whipple's disease. These symptoms began 2 months after the patient returned from military service in the Persian Gulf.

International migration and control of communicable diseases

The epidemiology and policy implications of communicable disease (CD) transmission associated with international migration have received little systematic study. This is a review of clinical and epidemiological reports in search of strategies to assess and manage the impact of international migration on the transmission of CDs. The economics and demography of migration from less developed to industrialized nations is considered. Migration-related transmission should differentiate between actual transmission as opposed to geographic relocation of disease. Limitations of current screening and disease prevention strategies are discussed. Social and ecological processes through which migration can contribute to increased CD transmission are described, including placement in refugee camps, unclear legal status of migrants in recipient nations, and temporary return migration. Strategies for non-discriminatory and non-punitive control of migration-related CDs, needed changes in clinical practice, and complexities presented by CDs of long latency (such as HIV infection) are reviewed.

Isolation of virulence genes directing surface glycosyl-phosphatidylinositol synthesis by functional complementation of Leishmania

Trypanosomatid parasites of the genus Leishmania cause a spectrum of widespread tropical diseases. In the vertebrate host they reside within the macrophage phagolysosome; however, the mechanisms employed in this remarkable survival strategy are not well understood. Recent advances in the molecular genetics of these parasites prompted us to develop methods of functional genetic complementation in Leishmania and apply them to the isolation of genes involved in the biosynthesis of the virulence determinant lipophosphoglycan, an abundant glycosyl-phosphatidylinositol-anchored polysaccharide. LPG1, the gene product identified by complementation of the R2D2 mutant, appears to be a glycosyltransferase responsible for the addition of galactofuranosyl residues to the nascent lipophosphoglycan chain. As galactofuranose is not found in mammalian cells, inhibition of the addition of this sugar could be exploited for chemotherapy. Overall, the success of the functional complementation approach opens the way to the identification of a variety of genes involved in pathogenesis and parasitism.

Visceral infection caused by Leishmania tropica in veterans of Operation Desert Storm

BACKGROUND

Visceral leishmaniasis, usually caused by Leishmania donovani, has rarely been reported from eastern Saudi Arabia, so it was not expected to affect the soldiers of Operation Desert Storm.

METHODS

We evaluated eight soldiers with visceral leishmanial infection, examining their serum with an immunofluorescent-antibody assay, examining their marrow or biopsy tissue for amastigotes with an indirect immunofluorescent-monoclonal-antibody assay, and culturing the parasites. Cultured promastigotes were isolated and characterized by isoenzyme analysis.

RESULTS

None of the eight soldiers had classic signs or symptoms of visceral leishmaniasis (kala-azar). Seven soldiers had unexplained fever, chronic fatigue, malaise, cough, intermittent diarrhea, or abdominal pain that began up to seven months after they returned to the United States; one had no symptoms. Five had adenopathy or mild, transient hepatosplenomegaly. None had cutaneous manifestations. Diagnoses were made by bone marrow aspiration (seven patients) or lymph-node biopsy (one patient). Six isolates have been identified as L. tropica, which usually causes only cutaneous disease. Of the six patients treated with sodium stibogluconate, five improved and one remained symptomatic.

CONCLUSIONS

L. tropica can produce visceral infection that can cause unexplained systemic illness in persons returning from areas where this organism is endemic.

[Epidemiology and clinical aspects of imported tropical diseases]

The number of people travelling of the tropical countries is in constant progression and today represents about 5% of the population of the developed countries. Mortality is mainly accidental. Morbidity essentially concerns transmissible diseases. Diarrhoeal symptoms occur in 20-55% of travellers, are bacterial in 2 cases out of 3, and can be prevented. Cholera should soon have an efficient oral vaccine. Hepatitis A is frequent in some travellers (2-3%) and can be prevented by vaccination. Hepatitis E is beginning to be observed. Strongyloidiasis can in some cases evolve to serious complications; it may be latent, so should be sought systematically after any visit to the tropics. Most affections on returning to the industrialised world concern paludism of the Plasmodium falciparum type, leading to a still high mortality rate of 400 per year in Europe, while the preventive and curative means available are sufficient. Any fever should therefore be suspected and suitable treatment given. Other causes of fever are acute viral hepatitis, typhoid fever, the arboviroses, and numerous other conditions. Dermatoses represent the third reason for consultation on returning. These mainly concern pruriginous symptoms with filariases and abnormal hosts being evidenced. Furunculous lesions indicate a diagnosis of cutaneous leishmaniosis or myases. Any form of pruritus should suggest a diagnosis of HIV infection, or pruritus should suggest a diagnosis of HIV infection, or particularly trypanosomiasis. The risk of sexually transmissible disease is overall 6-fold higher in tropical travellers; advice before travelling is therefore of paramount importance. Should a seropositive subject travel to the tropics?(ABSTRACT TRUNCATED AT 250 WORDS)

Travel to the Persian Gulf. Medical guidelines for visitors

The disease, destruction, and destitution created by the recent conflicts in the Persian Gulf have resulted in increased international travel to affected countries for relief and reconstruction. Such travel involves more than minimal health risks, but effective preparation of travelers by primary care physicians can help, as discussed by the authors.

Diarrheal disease during Operation Desert Shield

BACKGROUND

Under combat conditions infectious disease can become a major threat to military forces. During Operation Desert Shield, there were numerous outbreaks of diarrhea among the U.S. forces. To evaluate the causes of and risk factors for diarrheal disease, we collected clinical and epidemiologic data from U.S. troops stationed in northeastern Saudi Arabia.

METHODS

Between September and December 1990, stool cultures for enteric pathogens were obtained from 432 military personnel who presented with diarrhea, cramps, vomiting, or hematochezia. In addition, a questionnaire was administered to 2022 soldiers in U.S. military units located in various regions of Saudi Arabia.

RESULTS

A bacterial enteric pathogen was identified in 49.5 percent of the troops with gastroenteritis. Enterotoxigenic Escherichia coli and Shigella sonnei were the most common bacterial pathogens. Of 125 E. coli infections, 39 percent were resistant to trimethoprim-sulfamethoxazole, 63 percent to tetracycline, and 48 percent to ampicillin. Of 113 shigella infections, 85 percent were resistant to trimethoprim-sulfamethoxazole, 68 percent to tetracycline, and 21 percent to ampicillin. All bacterial isolates were sensitive to norfloxacin and ciprofloxacin. After an average of two months in Saudi Arabia, 57 percent of the surveyed troops had at least one episode of diarrhea, and 20 percent reported that they were temporarily unable to carry out their duties because of diarrheal symptoms. Vomiting was infrequently reported as a primary symptom, but of 11 military personnel in whom vomiting was a major symptom, 9 (82 percent) had serologic evidence of infection with the Norwalk virus.

CONCLUSIONS

Gastroenteritis caused by enterotoxigenic E. coli and shigella resistant to a number of drugs was a major problem that frequently interfered with the duties of U.S. troops during Operation Desert Shield.