Showing papers on "Visceral leishmaniasis published in 2006"

Drug Resistance in Leishmaniasis

Abstract: Leishmaniasis is a complex disease, with visceral and cutaneous manifestations, and is caused by over 15 different species of the protozoan parasite genus Leishmania. There are significant differences in the sensitivity of these species both to the standard drugs, for example, pentavalent antimonials and miltefosine, and those on clinical trial, for example, paromomycin. Over 60% of patients with visceral leishmaniasis in Bihar State, India, do not respond to treatment with pentavalent antimonials. This is now considered to be due to acquired resistance. Although this class of drugs has been used for over 60 years for leishmaniasis treatment, it is only in the past 2 years that the mechanisms of action and resistance have been identified, related to drug metabolism, thiol metabolism, and drug efflux. With the introduction of new therapies, including miltefosine in 2002 and paromomycin in 2005-2006, it is essential that there be a strategy to prevent the emergence of resistance to new drugs; combination therapy, monitoring of therapy, and improved diagnostics could play an essential role in this strategy.

Current scenario of drug development for leishmaniasis.

Abstract: Although three new drugs or drug formulations, liposomal amphotericin B (AmBisome), miltefosine and paromomycin should be available for the treatment of visceral leishmaniasis (VL) within the next year, they all suffer from limitations of either cost, specific toxicities or parenteral administration. As part of research to identify better treatments for VL and cutaneous leishmaniasis (CL), alternative and potentially cheaper formulations of amphotericin B, alklyphosphocholines other than miltefosine and improved formulations of paromomycin for CL have been identified. Other drugs or compounds that have demonstrated activity in experimental rodent models of infection include licochalcone derivatives, quinoline derivatives, bisphosphonates and a maesabalide; further chemistry based upon these leads is warranted. The process for discovery and development of new antileishmanials would also benefit from improved models, for example, transfected parasites, and non invasive methods of measuring parasite load in rodent models of infection.

Immunology of canine leishmaniasis.

Abstract: The role of dogs as the main reservoir of visceral leishmaniasis has led to an increased interest in the immune responses and in Leishmania antigens implicated in protective cellular immunity in canine visceral leishmaniasis. The primary goal is to control the prevalence of human disease. Immune responses in canine visceral leishmaniasis are reviewed. Cellular immune responses toward a Th1 subset mediated by IFN-gamma and TNF-alpha predominate in asymptomatic dogs exhibiting apparent resistance to visceral leishmaniasis. On the other hand, while the role of Th2 cytokines, such as IL-4 and IL-10, in symptomatic animals is still controversial, there is increasing evidence for a correlation of these cytokines with progressive disease. CD8+ cytotoxic T cells seem also likely to be involved in resistance to visceral leishmaniasis. Several Leishmania antigens implicated in protective immune responses are described and some pivotal points for development of an effective vaccine against canine visceral leishmaniasis are discussed.

Visceral leishmaniasis in Brazil: revisiting paradigms of epidemiology and control

Abstract: In the last 20 years, despite the known underestimation of cases, Brazil registered a marked increase in the incidence of visceral leishmaniasis. The main goal of this review is to reflect on some aspects of this zoonosis in Brazil and also to encourage the discussion in order to find more viable, effective and affordable strategies to be implemented by the Brazilian Leishmaniasis Control Program. The current situation of visceral leishmaniasis in Brazil might be seen as a paradox: the most important aspects of the disease are known, but so far the control of this disease has not yet been achieved. The current control strategies have not been able to prevent the geographical expansion, and even a rise in the incidence and lethality of visceral leishmaniasis. There is a need not only for a better definition of priority areas, but also for the implementation of a fieldwork monitoring system to the disease surveillance that could permit a further evaluation of the control program in areas where visceral leishmaniasis is endemic.

Leishmaniasis vaccine candidates for development: a global overview.

Abstract: A vaccine against different forms of leishmaniasis should be feasible considering the wealth of information on genetics and biology of the parasite, clinical and experimental immunology of leishmaniasis, and the availability of vaccines that can protect experimental animals against challenge with different Leishmania species However, there is no vaccine against any form of leishmaniasis for general human use One major factor is the lack of a conceived market for human leishmaniasis vaccines Hence pharmaceutical industries involved in vaccine development are not interested in investing millions of dollars and a decade that is required for developing a new vaccine Besides, leishmaniasis is a local/regional problem and not a global one According to the estimates of the World Health Organization, 90 per cent of visceral leishmaniasis occurs in five countries (Bangladesh, Brazil, India, Nepal and Sudan) Those in need are amongst the poorest people in these countries It should therefore be the objectives of these countries to develop a vaccine Fortunately, both Brazil and India have designated the control of visceral leishmaniasis as a top priority for their respective Ministries of Health The purpose of this review is to present only the vaccines in use and those in development for use in dogs or humans This is not an exhaustive review of vaccine discovery or the principles of clinical immunology underlying vaccine development

Canine Visceral Leishmaniasis, United States and Canada, 2000-2003

Abstract: Visceral leishmaniasis, caused by protozoa of the genus Leishmania donovani complex, is a vectorborne zoonotic infection that infects humans, dogs, and other mammals. In 2000, this infection was implicated as causing high rates of illness and death among foxhounds in a kennel in New York. A serosurvey of >12,000 foxhounds and other canids and 185 persons in 35 states and 4 Canadian provinces was performed to determine geographic extent, prevalence, host range, and modes of transmission within foxhounds, other dogs, and wild canids and to assess possible infections in humans. Foxhounds infected with Leishmania spp. were found in 18 states and 2 Canadian provinces. No evidence of infection was found in humans. The infection in North America appears to be widespread in foxhounds and limited to dog-to-dog mechanisms of transmission; however, if the organism becomes adapted for vector transmission by indigenous phlebotomines, the probability of human exposure will be greatly increased.

Resistance to Antimony and Treatment Failure in Human Leishmania (Viannia) Infection

Abstract: Background. Failure of antimonial therapy has been increasingly reported in anthroponotic visceral leishmaniasis and in cutaneous disease. The role of drug resistance in treatment failure has been difficult to ascertain because therapeutic response is multifactorial, and the efficacy of antimonial drugs depends on an effective immune response. In this study, we sought to determine whether standard treatment selects for resistant organisms and whether drug resistance contributes to treatment failure. Methods. We evaluated the susceptibility to antimony of 19 strains isolated before treatment with meglumine antimoniate and 21 strains isolated at treatment failure from 20 patients. The 50% effective dose (ED 50 ) of antimony in the form of additive-free meglumine antimoniate was determined for intracellular amastigotes in human promonocytic U-937 cells. Results. Before treatment, 16% of strains (3/19) showed primary resistance (ED 50 of>128 μg Sb/mL), whereas 84% (16/19) were susceptible (ED 50 of 128 μg Sb/mL. At treatment failure, 40% of strains (8/20) were resistant. Secondary resistance was documented in 4 patients. Conclusions. Primary and secondary resistance to antimony can contribute to treatment failure in American cutaneous leishmaniasis. Selection for resistance to antimony occurs during standard treatment with antimonial drugs, and primary resistance to antimony supports the plausibility of anthroponotic transmission.

Development of miltefosine as an oral treatment for leishmaniasis

Abstract: Miltefosine was originally formulated and registered as a topical treatment for cutaneous cancers. For this indication and in subsequent development for leishmaniasis, a large body of non-clinical data has been generated. The gastrointestinal organ is the main site of toxicity, in both animal and in human studies. The testis and retina were identified as target organs in rats, although corresponding changes were not observed in clinical studies in humans. In terms of pharmacokinetics, the terminal elimination half-life is long (84h and 159h in rats and dogs respectively). Miltefosine is widely distributed in body organs and not metabolized by cytochrome P450 enzymes in vitro. The drug is embryotoxic and fetotoxic in rats and rabbits, and teratogenic in rats but not in rabbits. It is therefore contraindicated for use during pregnancy, and contraception is required beyond the end of treatment in women of child-bearing age.

Application of Direct Agglutination Test (DAT) for the Diagnosis and Seroepidemiological Studies of Visceral Leishmaniasis in Iran

Abstract: Visceral leishmaniasis (VL) is one of the most important parasitic diseases which is endemic in different parts of Iran. Serological studies were conducted by direct agglutination test (DAT) on 12144 human serum samples, collected from four geographical zones of Iran. Sero prevalence, geographical distribution, clinical signs and symptoms for human visceral leishmaniasis based on DAT for the period of 2002 through 2005 were determined. From 516 kala-azar cases detected: 50.6% were from Meshkin-shahr and Moghan districts in Ardabil Province, northwest of Iran and 49.4% were detected from other areas of Iran. In physical examination of seropositive cases, which were detected by DAT with anti-leishmanial antibodies at titers of 1: 3200 to 1: 102400, almost 50% of suspected individuals showed the classical kala-azar signs and symptoms. Predominant signs and symptoms in 233 hospitalized patients with anti-Leishmania antibodies at 1:3200 and higher, were fever (88.0%) and splenomegaly (84.5%). Statistically significant difference was found between males (58%) and females (42%) (P< 0.01). Moreover, 93.6% of the VL patients were < 5 yr of age, and 6.4% were older than 5 yr that this difference was statistically significant (P< 0.01). From 1383 serum samples collected from domestic dogs in the villages that are known as endemic foci of human leishmaniasis, 152 (11.0%) were positive by DAT (≥ 1:320). Parasitological and serological examinations that were performed in 30 wild canines showed that 10% of these animals were infected by L. infantum. L. infantum Lon49 is the principal agent of the disease in human as well as animal reservoir hosts in different parts of Iran. For the first time in Iran, L. tropica isolated from both skin lesions in the face and bone marrow aspiration in a HIV + man who co-infected with VL as well as in an infected dog from Ardabil Province.

Miltefosine — discovery of the antileishmanial activity of phospholipid derivatives

Abstract: Miltefosine (hexadecylphosphocholine, Impavidotrade mark), a novel antiprotozoal drug used for the treatment of visceral and cutaneous leishmaniasis, was identified and evaluated independently in the early 1980s as a potential anticancer drug in Germany and as an antileishmanial drug in the UK. Although miltefosine is not the most active compound of its class against Leishmania parasites in vitro, the early demonstration of activity after oral administration in experimental models of visceral leishmaniasis helped to bring this compound to the attention of WHO TDR for further development in a unique collaboration model with the pharmaceutical industry (Zentaris GmbH). Miltefosine is active against most Leishmania species, including those that cause cutaneous disease.

Animal models for vaccine studies for visceral leishmaniasis.

Abstract: Received April 7, 2005Visceral leishmaniases (VL) or kala-azar is the most dreaded and devastating amongst the variousforms of leishmaniases. The disease, though localized in certain areas only, has gained immenseimportance because of high mortality rate, mainly in children. The parasite is responsible for aspectrum of clinical syndromes, which can, in most extreme cases, go from an asymptomatic infectionto a fatal form of VL. Chemotherapeutic measures, alone are not sufficient to control and containthe disease. As an alternate strategy, vaccination is also under experimental and clinical trails.The situation unquestionably demands the use of proper screening system, rationale chemicalsynthesis, vaccine development and targeted vaccine delivery. Thus, development of an acceptablevaccine is not an easy task.While the factors, which determine clinical outcomes, are in part, a feature of the parasite, it is thenature of the host and its genetic make up and immune status that play crucial role. The prerequisiteof reliable animal model is that it should have a considerably good correlation with the clinicalsituation and is expected to mimic the pathological features and immunological responses observedin humans when exposed to a variety of Leishmania spp. with different pathogenic characteristics.Many experimental animal models like rodents, dogs and monkeys have been developed, each withspecific features, but none accurately reproduces what happens in humans. In addition to thenature of the host, the major difference between natural and experimental infections is the parasiteinoculum; in natural conditions, the infected sand fly vector deposits a few hundred metacyclicpromastigotes into the dermis of the host, whereas experimental infections are induced by theinjection (subcutaneous or intravenous) of millions of promastigotes grown in axenic cultures invitro or amastigotes recovered from infected spleens.In public health terms, VL is the disease of humans and dogs (which may be considered secondaryor ‘accidental’ hosts in the leishmanial life cycle) who often exhibit severe clinical signs andsymptoms when infected, whereas reservoir hosts generally show a few, minor or no signs. Thissituation makes the definition of a suitable laboratory model a difficult one since the variousexperimental hosts may behave either like a reservoir or an accidental host.This review discusses the concept of animal models for VL and provides a critical evaluation of themost common experimental models and their respective advantages and disadvantages. Particularemphasis is given to the value of using mouse, hamster, dog and primate models, especially in thecontext of testing potential antileishmanial vaccines.Key words Amastigotes - dog - hamster - mice - monkey - promastigotes - vaccines - visceral leishmaniasis

The epidemiology of visceral leishmaniasis in Bangladesh: prospects for improved control.

Abstract: The parasitic disease kala-azar (visceral leishmaniasis, VL) was first described in 1824 in Jessore district, Bengal (now Bangladesh) Epidemic peaks were recorded in Bengal in the 1820s, 1860s, 1920s, and 1940s After achieving good control of the disease during the intensive vector control efforts for malaria in the 1950s-1960s, Bangladesh experienced a VL resurgence that has lasted to the present Surveillance data show an increasing trend in incidence since 1995 Research in recent years has demonstrated the utility of non-invasive diagnostic modalities such as the direct agglutination test and rapid tests based on the immune response to the rK39 antigen In common with its neighbours India and Nepal, VL in Bangladesh is anthroponotic Living in proximity to a kala-azar case is the strongest risk factor for disease, while consistent use of bed nets in the summer months and the presence of cattle are protective Shortages of first-line antileishmanial drugs and insecticide for indoor spraying programmes have hindered VL treatment and vector control efforts Effective control of VL will require activities to improve availability and access to diagnostic testing and antileishmanial drugs, enhanced surveillance for kala-azar, post-kala-azar dermal leishmaniasis and VL treatment failures, and increased coverage and efficacy of vector control programmes

Visceral leishmaniasis (kala-azar): Challenges ahead

Abstract: Indian visceral leishmaniasis (VL) is a parasitic disease caused by a haemoflagellete Leishmania donovani and transmitted by the bite of sand fly Phlebotomus argentipes. It affects various age groups. In India about 1,00,000 cases of VL are estimated to occur annually; of these, the State of Bihar accounts for over than 90 per cent of the cases. Diagnosis of VL typically relies on microscopic examination of tissue smears but serology and molecular methods are better alternatives currently. Notwithstanding the growing incidence of resistance, pentavalent antimony complex has been the mainstay for the treatment of VL during the last several decades. The second line drugs such as amphotericin B, lipid formulations of amphotericin B, paromomycin and recently developed miltefosine are the other alternatives. In spite of significant development in various areas of Leishmania research, there is a pressing need for the technological advancement in the understanding of immune response, drug resistance and the pathogenesis of leishmaniasis that could be translated into field applicable and affordable methods for diagnosis, treatment, and control of the disease.

Challenges in the diagnosis of post kala-azar dermal leishmaniasis.

Abstract: Post kala-azar dermal leishmaniasis (PKDL) is a dermatosis that occurs as a sequel of visceral leishmaniasis (VL). Elimination of VL requires detection and treatment of PKDL, necessarily because of its capacity to serve as a reservoir for the causative parasite, Leishmania donovani. Diagnosis of PKDL presents a challenge due to low parasite burden in the lesions. In this article we have reviewed the recent advances in the development of immunological and molecular methods for diagnosis of PKDL.

Mixed inflammatory/regulatory cytokine profile marked by simultaneous raise of interferon-gamma and interleukin-10 and low frequency of tumour necrosis factor-alpha(+) monocytes are hallmarks of active human visceral Leishmaniasis due to Leishmania chagasi infection.

Abstract: Considering the complexity of the immunological events triggered during active visceral Leishmaniasis (VL), the relevance of the segregation of the immune response during human VL into type 1 and type 2 still remains unclear. For this purpose, in individuals living in risk areas for VL, we have evaluated especially asymptomatic individuals and patients with active VL, the plasmatic levels of cytokines and reactive nitrogen species under ex vivo conditions. In addition, we have also performed an analysis of intracellular cytokine patterns of circulating leucocytes after short-term culture, particularly in the absence of antigenic-specific stimulation, in order to reflect dynamic events of immune response in vivo during Leishmania chagasi infection. Although asymptomatic individuals and non-infected subjects presented a similar immunological profile, an outstanding inflammatory/regulatory profile, based on higher plasmatic levels of cytokines such as interleukin (IL)-8, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, IL-6 and IL-10, was associated with clinical status observed in active VL. In this context, we hypothesize that IL-10, through its ability to inhibit anti-leishmanial macrophage activation, associated with the lower frequency of TNF-alpha(+) monocytes and ordinary levels of nitrite and nitrate are the major mechanisms associated with disease onset.

Oral miltefosine for the treatment of Indian visceral leishmaniasis.

Abstract: Summary Large-scale antimony resistance in the treatment of visceral leishmaniasis (VL) in north Bihar, India, has led to the development of miltefosine as an alternative therapy. In a pilot study and later in three Phase II studies involving 249 patients, oral miltefosine, 100–150 mg/day for 28 days, was shown to cure ∼90% patients with reasonable safety. In the pivotal Phase III trial, 299 patients were treated at three centres with amphotericin B as the comparator drug (99 patients). In this trial 38% and 20% patients had mild to moderate vomiting and diarrhoea respectively, similar to previous studies. Asymptomatic transient elevation of hepatic transaminases and mild renal dysfunction were observed in 15% and 10% patients respectively. The final cure rate was 94% with miltefosine and 97% with amphotericin B; based on these results, the drug was approved in India. Subsequently in two paediatric studies involving 119 patients in the age group of 2–11 years, the safety and efficacy of miltefosine (2.5 mg/kg daily for 28 days) was established with a cure rate (94%) similar to that seen in adults. Miltefosine is the first oral antileishmanial drug with a high degree of safety and efficacy for the treatment of VL.

Comparison of New Diagnostic Tools for Management of Pediatric Mediterranean Visceral Leishmaniasis

Abstract: New techniques are available for diagnosing leishmaniasis, but their efficacy in the identification of pediatric visceral leishmaniasis (VL) has not been compared with that of traditional methods. Blood, bone marrow, and urine samples were taken from 25 children with VL during their first clinical episode, 22 days after the start of treatment with liposomal amphotericin B (3 mg/kg/day on 6 days over a 10-day period), and when a relapse was suspected during follow-up. The results obtained suggest that antibody detection techniques, the antigen detection in urine (KAtex kit), and Leishmania nested PCR (LnPCR) analysis of the blood could be used for diagnosis of the first clinical episode. After treatment, clinical improvement was associated with negativization of Novy-MacNeal-Nicolle culture and microscopy of bone marrow aspirate, KAtex test, and LnPCR blood analysis results. Interestingly, LnPCR analysis of the bone marrow aspirate showed that sterile cure was not achieved in eight patients, two of which suffered a relapse within 10 to 20 weeks. All of the new noninvasive techniques tested showed high diagnostic sensitivity. However, LnPCR analysis of the bone marrow was the most sensitive; this test was able to detect the persistence of parasites and predict potential relapses.

Epidemiology of visceral leishmaniasis through spatial analysis, in Belo Horizonte municipality, state of Minas Gerais, Brazil.

Abstract: The geographic information system approach has permitted integration between demographic, socio-economic and environmental data, providing correlation between information from several data banks. In the current work, occurrence of human and canine visceral leishmaniases and insect vectors (Lutzomyia longipalpis) as well as biogeographic information related to 9 areas that comprise the city of Belo Horizonte, Brazil, between April 2001 and March 2002 were correlated and georeferenced. By using this technique it was possible to define concentration loci of canine leishmaniasis in the following regions: East; Northeast; Northwest; West; and Venda Nova. However, as for human leishmaniasis, it was not possible to perform the same analysis. Data analysis has also shown that 84.2% of the human leishmaniasis cases were related with canine leishmaniasis cases. Concerning biogeographic (altitude, area of vegetation influence, hydrographic, and areas of poverty) analysis, only altitude showed to influence emergence of leishmaniasis cases. A number of 4673 canine leishmaniasis cases and 64 human leishmaniasis cases were georeferenced, of which 67.5 and 71.9%, respectively, were living between 780 and 880 m above the sea level. At these same altitudes, a large number of phlebotomine sand flies were collected. Therefore, we suggest control measures for leishmaniasis in the city of Belo Horizonte, giving priority to canine leishmaniasis foci and regions at altitudes between 780 and 880 m.

Immunohistological features of visceral leishmaniasis in BALB/c mice

Abstract: SUMMARY It has been reported that the level of protection provided by vaccines against murine visceral leishmaniasis (VL) is low and that progress in research on VL may be due to the lack of appropriate models to study protective immunity. We have analysed the immunohistological features occurring in BALB/c mice after intravenous administration of 10 3 , 10 5 and 10 6 parasites of Leishmania infantum . Our results show that in all cases parasite administration leads to the establishment of infection and to the development of quantifiable immunohistological features which are dependent on the inoculum size. This study demonstrates that differences in the parasite challenge result in changes in the evolution of some of the parameters associated with the degree of the infection in the BALB/c model: level of anti- Leishmania antibodies, upregulation of spleen arginase activity, balance between IFN- γ and IL-10, extent of lymphoid follicle depletion in the splenic white pulp and ineffective development of hepatic granulomas. Also, and depending on the initial infectious inoculum, the absence of parasites in the bone marrow and the number of mature and empty type granulomas were parameters associated with protection. We think that in this model a challenge of the order of 10 5 parasites should prove useful for vaccine studies against VL.

Phenotypic features of circulating leucocytes as immunological markers for clinical status and bone marrow parasite density in dogs naturally infected by Leishmania chagasi.

Abstract: Canine visceral leishmaniasis (CVL) manifests itself as a broad clinical spectrum ranging from asymptomatic infection to patent severe disease. Despite relevant findings suggesting changes on lymphocytes subsets regarding the CVL clinical forms, it still remains to be elucidated whether a distinct phenotypic profile would be correlated with degree of tissue parasite density. Herein, we have assessed the correlation between the clinical status as well as the impact of bone marrow parasite density on the phenotypic profile of peripheral blood leucocytes in 40 Brazilian dogs naturally infected by Leishmania chagasi. Our major findings describe the lower frequency of B cells and monocytes as the most important markers of severe CVL. Our main statistically significant findings reveal that the CD8(+) T cell subset reflects most accurately both the clinical status and the overall bone marrow parasite density, as increased levels of CD8(+) lymphocytes appeared as the major phenotypic feature of asymptomatic disease and dogs bearing a low parasite load. Moreover, enhanced major histocompatibility complex (MHC)-II density as well as a higher CD45RB/CD45RA expression index seems to represent a key element to control disease morbidity. The association between clinical status, bone marrow parasitism and CD8(+) T cells re-emphasizes the role of the T cell-mediated immune response in the resistance mechanisms during ongoing CVL. Higher levels of circulating T lymphocytes (both CD4(+) and CD8(+) T cells) and lower MHC-II expression by peripheral blood lymphocytes seem to be the key for the effective immunological response, a hallmark of asymptomatic CVL.

Evaluation of a new recombinant k39 rapid diagnostic test for sudanese visceral leishmaniasis

Abstract: A new rK39 rapid diagnostic dipstick test (DiaMed-IT-Leish) was compared with aspiration and a direct agglutination test (DAT) for diagnosis of visceral leishmaniasis (VL) in 201 parasitologically confirmed cases, 133 endemic controls, and in 356 clinical suspects in disease-endemic and -epidemic areas in Sudan. The sensitivity of the rK39 test in parasitologically confirmed VL cases was 90%, whereas the specificity in disease-endemic controls was 99%. The sensitivity of the DAT was 98%. In clinically suspected cases, the sensitivity of the rK39 test was 81% and the specificity was 97%. When compared with the diagnostic protocol based on the DAT and aspiration used by Medecins sans Frontieres in epidemic situations, the positive predictive value was 98%, and the negative predictive value was 71%. This rK39 rapid diagnostic test is suitable for screening as well as diagnosis of VL. Further diagnostic work-up of dipstick-negative patients with clinically suspected VL is important. The ease and convenience of the dipstick test will allow decentralization and improved access to care in disease-endemic areas in Sudan.

Leishmaniasis in ancient Egypt and Upper nubia.

Abstract: To the Editor: Leishmaniasis is a disease caused by parasites of the genus Leishmania. The infection is transmitted to humans through the bites of female sandflies and manifests mainly in 3 forms: visceral, cutaneous, and mucocutaneous. Visceral leishmaniasis or kala-azar, the often fatal form of the disease, is caused by species of the Leishmania donovani complex. These parasites were responsible for severe recent outbreaks in Sudan and other countries and are thought to originate in East Africa (1–4). In this report, we describe the successful amplification of L. donovani DNA in ancient Egyptian and Christian Nubian mummies dating back 4,000 years. Besides the first proof for visceral leishmaniasis in paleopathology, we provide evidence that leishmaniasis was present in Nubia in the early Christian period and that the organism also infected ancient Egyptians, probably because of close trading contacts to Nubia, during the Middle Kingdom. We analyzed 91 bone tissue samples from ancient Egyptian mummies and skeletons and 70 bone marrow samples from naturally mummified human remains from Upper Nubia. The Egyptian material derived from the Pre- to Early Dynastic site of Abydos (n = 7; 3500–2800 BC), a Middle Kingdom tomb in Thebes West (42; 2050–1650 BC), and different tomb complexes in Thebes West, which were built and used between the Middle and New Kingdom until the Late Period (42; c. 2050–500 BC). The Nubian samples were taken before the flooding caused by the Aswan Dam from 2 early Christian burial sites at Kulubnarti, between the second and third cataracts of the Nile River in northern Sudan. One site was on an island in the Nile and dated from 550 to 750 AD. The other was on the western bank of the Nile and was in use from c.750 to 1500 AD. All samples were tested for Leishmania spp. DNA and further characterized by direct sequencing. In 4 of the 91 Egyptian and 9 of the 70 Nubian samples, a 120-bp fragment of a conserved region of the minicircle molecule of kinetoplastid mitochondrial DNA of the parasite (5,6) could be successfully amplified and, with the first primer pair, unambiguously related to L. donovani species after sequencing (Figure). The positive samples from ancient Egypt exclusively originated from the Middle Kingdom tomb, while no molecular evidence for ancient Leishmania DNA was found in the Pre- to Early Dynastic and the New Kingdom to Late Period specimens. Figure PCR amplification of a 120-bp fragment of kinetoplastid mitochondrial DNA of Leishmania spp. in Egyptian and Nubian mummies. Lane 1, 50-bp ladder lanes 2–8, mummy samples; lanes 9,10, extraction controls; lane 11, PCR controls. Lane 6 provides ... In the Middle Kingdom, the Egyptians extended trade relationships and military expeditions to Nubia, the modern Sudan, with particular interest in the gold resources of the country and in obtaining slaves to serve as servants or soldiers in the pharaoh’s army. Today, the Sudan is one of the highly endemic countries for visceral leishmaniasis or kala-azar, which is thought to have originated in East Africa and later spread to the Indian subcontinent and the New World (4). Therefore, the high incidence of Leishmania DNA in the Middle Kingdom samples (4 [9.5%] of 42) and the lack of findings in earlier or later time periods, may indicate that leishmaniasis was introduced into Egypt at this time. Leishmaniasis did not likely become endemic in the Egyptian Nile Valley because the disease is closely linked to its vector, the phlebotomine sandfly, and the distribution of Acacia-Balanites woodland (7). That ancient Egyptians became infected because of close trade contacts and associated travel with Nubia during the Middle Kingdom seems more plausible. The high frequency of Leishmania DNA–positive samples in the Nubian mummies (12.9%) suggests that leishmaniasis was endemic in Nubia during the Early Christian period and, in light of the data on the ancient Egyptian mummies, probably already several thousand years before. Taken together, our results support the theory that Sudan could have been indeed the original focus of visceral leishmaniasis (4). Our study shows a completely new aspect of molecular paleopathology. The detection of ancient pathogen DNA is not only used to identify a certain disease and gain information on its frequency and evolutionary origin but also to trace back cultural contacts and their role in the transmission and spread of infectious diseases.