Autochthonous Visceral Leishmaniasis Research Articles

ANNUAL ANALYSIS OF PARASITIC INFECTIONS IN BULGARIA IN 2022

INTRODUCTION: Infections caused by parasites still represent an important global health problem. Although parasitic infections are responsible for significant morbidity and mortality in developing countries, they are also prevalent in developed countries. This study aims to establish the dynamics of the parasitic infections registered in the country (local and imported) and to analyze the situation, based on data from the previous years. METHODS: We used the annual reports of regional health inspectorates, diagnostic laboratories, medical universities, and data from the National center of infectious and parasitic diseases about all individuals infected with parasitic diseases in the country. RESULTS: A total of 635,522 persons were examined in 2022, of whom 1.82% were diagnosed with various parasitic infections. In the local helminthic zoonoses such as echinococcosis and trichinellosis, a significant decrease in morbidity was observed,1.3%₀₀₀ (n = 89) for cystic echinococcosis and 0.16%₀₀₀ (n = 9) for trichinellosis. For soil-transmitted helminthiases (ascariasis and trichuriasis), the incidence was 6.7%₀₀₀ and 0.5%₀₀₀, respectively. Data on enterobiasis does not show any particular dynamics in 2022 either. The registered prevalence for the country was 1.48%, and for children from various childcare facilities - 2.45%. During the year, seven cases of vector-borne parasitic diseases were registered in the country: imported malaria was diagnosed in 5 patients (4 Bulgarian citizens and one foreigner), and autochthonous visceral leishmaniasis - in two persons. CONCLUSIONS: The analysis shows that, in spite of a trend of declining morbidityfor some socially significant protozoan and helminth infections, human parasitic diseases still represent a significant problem with social and medical consequences for the population of our country. Therefore, it is necessary to preserve and strengthen the surveillance and control network by including new personnel in the medical parasitology structures.

Autochthonous visceral leishmaniasis in the Russian Federation and the role of polymerase chain reaction as an alternative diagnostic method

The aim of the work is to summarize the available literature data on cases of visceral leishmaniasis in children registered in the Russian Federation, as well as to describe our own clinical observation of autochthonous visceral leishmaniasis in a 9-year-old child, in the diagnosis of which the polymerase chain reaction (PCR) method was used.Materials and methods: a review of domestic and foreign literature over the past 20 years, including Internet resources, was carried out. We observed a 9-year-old child hospitalized in the Russian Children's Clinical Hospital. Leishmania DNA was determined in blood serum by PCR using the Amplisens – Leishmania-Fl reagent kit.Results. It was established that the infection of the patient observed by us occurred on the territory of the Russian Federation in the Crimea. The diagnosis of leishmaniasis was confirmed by morphological examination of the bone marrow and the detection of pathogen DNA in the blood serum by PCR.Conclusion. On the territory of the Russian Federation there are foci of autochthonous visceral leishmaniasis in the Crimea and the North Caucasus. Polymerase chain reaction is an alternative to bone marrow aspirate microscopy for the diagnosis of visceral leishmaniasis.

Vigilância epidemiológica da leishmaniose visceral: análise de indicadores e fatores ambientais associados

Objetivo: analisar os indicadores epidemiológicos da Leishmaniose Visceral (LV) em Parnaíba-PI no período de 2010 a 2014. Métodos: foram incluídos 45 casos novos de Leishmaniose Visceral Humana (LVH) autóctone, residentes em Parnaíba e população canina de 2787 cães. Os dados foram obtidos do Sistema de Informação de Agravos de Notificação (SINAN), Sistema de Informação sobre Mortalidade (SIM), Instituto Brasileiro de Geografia de Estatística (IBGE), inquérito canino do Centro de Controle de Zoonoses (CCZ) e questionários semiestruturados. Resultados: observou-se média de nove casos de LVH nos últimos cinco anos, classificando-se como área de transmissão intensa para LV. Ocorreu registro de LVH em todos os meses do ano, com maior número de notificações nos meses de junho (n= 8) e outubro (n=8). A soroprevalência canina foi de 16%, com variação entre 8% a 42% durante o período, ascendendo a partir de 2013, com razão de 1:10 de casos humanos em relação aos caninos. Conclusão: os resultados oferecem subsídios para planejamento estratégico no controle da LV, propondo focalizar intervenções nas áreas estratificadas, incrementando a efetividade das medidas de controle na região.

AUTOCHTHONOUS CASE OF CUTANEOUS LEISHMANIASIS IN HIV INFECTED PATIENT

Single cases of autochthonous visceral leishmaniasis are registered in the Crimea and Dagestan. The article presents the first case of autochthonous cutaneous leishmaniasis in an HIV infected resident of the Republic of Dagestan, where this disease had not previously been registered. The diagnosis was made on the basis of a parasitological study of material taken from an ulcer on the border between the upper lip and the right nostril. Examination of the patient revealed a high burden of HIV (4 473 014 copies/ml) and a low level of CD4+ (76×106/l; 9%), which indicated an advanced stage of HIV infection. The patient underwent antiretroviral therapy (treatment with amphotericin B), against which a good result was obtained. A decrease in viral load and an increase in the content of CD4 lymphocytes in the blood were noted. A scar has formed on the site of a leishmaniasis ulcer.

Dispersion of Lutzomyia longipalpis and expansion of visceral leishmaniasis in S\xe3o Paulo State, Brazil: identification of associated factors through survival analysis

BackgroundIn Brazil, visceral leishmaniasis (VL) is a serious public health problem because of its magnitude, geographical expansion and potential harms caused by illnesses, including death. However, VL is largely ignored in discussions of tropical disease priorities. Thus, this study aimed to identify factors associated with the expansion of VL and the dispersion of its vector, Lutzomyia longipalpis, in the municipalities of the State of São Paulo, Brazil.MethodsInformation about the date of vector detection and the confirmation of autochthonous VL occurrence in humans and canines in São Paulo were obtained between 1997 and 2014. Survival curves were calculated by the Kaplan-Meier and the Cox multiple regression models was used.ResultsThe presence of the Marechal Rondon highway showed the highest positive association with vector dispersion and canine and human VL expansion. The monthly maximum and minimum temperature averages recorded in the municipalities during the study period were also positively associated with these events. The presence of transverse highways was positively associated with the presence of the vector; the border with the State of Mato Grosso do Sul, the presence of a prison, microregion headquarters, and the presence of the Tietê River were positively associated with the occurrence of canine cases, while only the presence of prison was positively associated with the occurrence of human cases. The construction of the Bolivia-Brazil gas pipeline was not associated with any events.ConclusionsSurvival analysis enabled the identification of factors associated with vector dispersion and VL expansion, thus the results of this study may be useful to the improvement of VL surveillance and control activities in the State of São Paulo and throughout Brazil.

Prevalence and risk factors associated with leishmania infection in Trang Province, Southern Thailand

Background Autochthonous cutaneous and visceral leishmaniasis caused by Leishmania martiniquensis and Leishmania siamensis have been considered emerging infectious diseases in Thailand. The disease burden is significantly underestimated, especially the prevalence of Leishmania infection among HIV-positive patients. Methods A cross-sectional study was conducted to determine the prevalence and risk factors associated with Leishmania infection among patients with HIV/AIDS living in Trang Province, southern Thailand between 2015 and 2016. Antibodies against Leishmania infection were assayed using the direct agglutination test (DAT). DNA of Leishmania was detected by ITS1-PCR using the buffy coat. Species of Leishmania were also identified. Results Of 724 participants, the prevalence of Leishmania infection was 25.1% (182/724) using either DAT and/or PCR assays. Seroprevalence of Leishmania infection was 18.5% (134/724), while Leishmania DNA detected by PCR method was 8.4% (61/724). Of these, 24.9% (180/724) were asymptomatic, whereas 0.3% (2/724) were symptomatic VL and VL/CL. At least five species were identified, that is, L siamensis, L. martiniquensis, L. donovani complex, L. lainsoni, and L. major. Multivariate analysis showed that CD4+ levels Conclusions A magnitude of prevalence of underreporting Leishmania infection among Thai patients with HIV was revealed in this study. Effective public health policy to prevent and control disease transmission is urgently needed.

Autochthonous Canine Visceral Leishmaniasis in Urban Area of Porto Alegre, RS, Brazil

Background: Leishmaniasis is a chronic infectious disease caused by intracellular protozoan Leishmania that affects canine and human. The visceral leishmaniasis (VL) is caused by the Leishmania donovani complex, in which canines are the main reservoir for human VL. In Southern Brazil, case reports of this disease have increased, especially when canines are infected in endemic areas in the country. Canines usually present a systemic disease, characterized by cutaneous lesions, weight loss, generalized lymphadenopathy, hepatomegaly and splenomegaly. This report aims to describe the clinicalpathological features of a case of autochthonous VL in a canine of an urban area of Porto Alegre.Case: A male, mixed breed, dog , 7 year-old, resident at the East Side of Porto Alegre, living together with two other canines, presented at clinical examination progressive weight loss, associated with hyporexia and hyperthermia, evolving to lateral recumbency, paralisys, and death. At necropsy, the dog was cachectic with diffusely pale mucosae. Gross findings included liver enlarged, with multifocal firm brownish areas, spleen enlarged, showing multifocal firm round dark-red areas, and kidneys diffusely pale with evidentiated tranversal striations on cortical zone. At microscopic examination, there was on the spleen diffuse inflammatory infiltrate of macrophages with large cytoplasm containing multiple amastigotes. The liver, exhibited atrophy of hepatocytes and moderate multifocal inflammatory infiltrate in sinusoids of macrophages containing multiple amastigotes. These features were also observed moderately on lymph nodes and lamina propria of large intestine. Immunohistochemistry examination showed marked positive staining for Leishmania spp. in amastigotes located whitin the cytoplasm of macrophages of spleen, liver, lymph nodes and large intestine.Discussion: Canine leishmaniasis is a disease that affects both internal organs and skin. However, the condition is called VL mostly because it is associated with the same species that cause the visceral form in humans. In this case the canine presented liver, spleen and lymph node lesions; however no skin lesion was observed during the clinical examination. A serological evaluation of canids in East Side of Porto Alegre performed in 2005 showed that 3.5% of these dogs were positive for Leishmania; yet neither of these animals presented clinical signs. This demonstrates that the agent was already present, however only 3-10% of the canines infected develop clinical disease. In non-endemic areas VL is related to the migration of canids from endemic areas, where VL is common. However the canine here described was born, raised, and was living in Porto Alegre. Lutzomyia longipalpis is the main vector of VL and despite its wide distribution it was identified only in 2009 in Rio Grande do Sul State. Autochthonous cases of VL were reported in canines and humans in this state, confirming the hypothesis that the vector was widely distributed and it is now present in Porto Alegre, keeping the epidemiological cycle of that disease active. Canine VL occurs prior in humans, since canines are the main domestic reservoirs and are critical for the maintenance of this disease cycle. This is the first autochthonous VL in a canine of an urban area of Porto Alegre; therefore authorities should be alert, and new control measures must be taken to avoid the canine leishmaniasis outbreak due to its potential for zoonotic transmission.Keywords: leishmaniasis, canine, protozoan, immunohistochemistry.

Ecology of Lutzomyia longipalpis and Lutzomyia migonei in an endemic area for visceral leishmaniasis.

The main vector for visceral leishmaniasis (VL) in Brazil is Lutzomyia longipalpis. However, the absence of L. longipalpis in a region of autochthonous VL demonstrates the participation of other species in the transmission of the parasite. Studies conducted in La Banda, Argentina, and São Vicente Férrer, Pernambuco State, Brazil, have correlated the absence of L. longipalpis and the presence of L. migonei with autochthonous cases of VL. In São Vicente Férrer, Pernambuco, there was evidence for the natural infection of L. migonei with Leishmania infantum chagasi. Thus, the objective of this work was to assess the ecology of the sand flies L. longipalpis and L. migonei in Fortaleza, an endemic area for VL. Insect capture was conducted at 22 sampling points distributed across four regions of Fortaleza. In total, 32,403 sand flies were captured; of these, 18,166 (56%) were identified as L. longipalpis and 14,237 (44%) as L. migonei. There were significant density differences found between the vectors at each sampling site (indoors and outdoors) (p <0.0001). These findings confirm that L. migonei and L. longipalpis are distributed throughout Fortaleza, where they have adapted to an indoor environment, and suggest that L. migonei may share the role as a vector with L. longipalpis in the transmission of VL in Fortaleza.

FIRST CASE OF AUTOCHTHONOUS HUMAN VISCERAL LEISHMANIASIS IN THE URBAN CENTER OF RIO DE JANEIRO: CASE REPORT

Visceral leishmaniasis is an anthropozoonosis that is caused by protozoa of the genus Leishmania, especially Leishmania (Leishmania) infantum, and is transmitted to humans by the bite of sandflies of the genus Lutzomyia, such as Lutzomyia longipalpis. There are many reservoirs, including Canis familiaris. It is a chronic infectious disease with systemic involvement that is characterized by three phases: the initial period, the state period and the final period. The main symptoms are fever, malnutrition, hepatosplenomegaly, and pancytopenia. This article reports a case of a patient diagnosed with visceral leishmaniasis in the final period following autochthonous transmission in the urban area of Rio de Janeiro. The case reported here is considered by the Municipal Civil Defense and Health Surveillance of Rio de Janeiro to be the first instance of autochthonous visceral leishmaniasis in humans in the urban area of this city. The patient was discharged and is undergoing a follow-up at the outpatient clinic, demonstrating clinical improvement.

Épidémiologie des leishmanioses autochtones en France métropolitaine et d’outre-mer

Leishmania infantum is the only species occurring in metropolitan France; located in the Mediterranean part of the country, it is responsible for a highly enzootic canine disease, while the human endemicity is low, with about 23 cases yearly reported to the National Reference Centre of Leishmaniases, mainly visceral forms. In French Guyana, five Leishmania species occur in the Amazonian forest, of which L. guyanensis is the predominant species, and L. braziliensis is responsible for the most critical forms. The most frequent clinical feature is cutaneous leishmaniasis, with a mean annual incidence reaching 2 p. 1000, with some inter-annual fluctuations. In Martinique Island, recent studies have confirmed the presence of an ancestral Leishmania species, responsible for small cutaneous lesions, of mild evolution; the life cycle of this species remains unknown. In Guadeloupe Island, a few autochthonous visceral leishmaniasis cases have been reported, needing a prospective study.

Ongoing outbreak of visceral leishmaniasis in Bologna Province, Italy, November 2012 to May 2013

An increased number of autochthonous visceral leishmaniasis (VL) cases has recently been reported in Bologna Province in northern Italy. Over six months from November 2012 to May 2013, 14 cases occurred, whereas the average number of cases per year was 2.6 (range: 0-8) in 2008 to 2012. VL was diagnosed in a median of 40 days (range: 15-120) from disease onset. This delay in diagnosis shows the need for heightened awareness of clinicians for autochthonous VL in Europe.

Ongoing outbreak of visceral leishmaniasis in Bologna Province, Italy, November 2012 to May 2013

An increased number of autochthonous visceral leishmaniasis (VL) cases has recently been reported in Bologna Province in northern Italy. Over six months from November 2012 to May 2013, 14 cases occurred, whereas the average number of cases per year was 2.6 (range: 0-8) in 2008 to 2012. VL was diagnosed in a median of 40 days (range: 15-120) from disease onset. This delay in diagnosis shows the need for heightened awareness of clinicians for autochthonous VL in Europe. .

Multilocus characterization and phylogenetic analysis of Leishmania siamensis isolated from autochthonous visceral leishmaniasis cases, southern Thailand

BackgroundVisceral leishmaniasis (VL) caused by Leishmania siamensis is an emerging disease continuously reported in six southern provinces of Thailand. To date, the phylogenetic relationships among Leishmania isolates from Thai patients and other Leishmania species are still unclear and the taxonomic diversity needs to be established. In this study, the phylogenetic inference trees were constructed based on four genetic loci (i.e., SSU-rRNA, ITS1, hsp70, and cyt b), using DNA sequences obtained from autochthonous VL patients from southern Thailand and reference sequences of reported Leishmania isolates from other studies deposited in GenBank.ResultsPhylogenetic analyses of hsp70 and cyt b loci supported a clade comprised of L. siamensis isolates, which is independent to the other members in the genus Leishmania. In combination with genetic distance analysis, sequence polymorphisms were observed among L. siamensis isolates and two different lineages could be differentiated, lineages PG and TR. Phylogenetic analysis of the cyt b gene further showed that L. siamensis lineage TR is closely related to L. enrietti, a parasite of guinea pigs.ConclusionThe finding of this study sheds further light on the relationships of L. siamensis, both in intra- and inter-species aspects. This information would be useful for further in-depth studies on the biological properties of this important parasite.

A Series of Case Reports of Autochthonous Visceral Leishmaniasis, Mostly in Non-Endemic Hilly Areas of Nepal

The government of Nepal has committed to eliminate visceral leishmaniasis (VL) by 2015. The expansion of VL into new areas would constitute a major obstacle to achieving this goal. We report a series of autochthonous VL cases from areas currently considered non-endemic, mostly in hilly regions of Nepal.

A survey of sandflies in the affected areas of leishmaniasis, southern Thailand

Leishmania siamensis was firstly described as a causative agent of autochthonous visceral leishmaniasis in southern provinces of Thailand since 2008. The spread of leishmaniasis depends on the distribution of the vectors and reservoir hosts. Unfortunately, little is known about these vital factors. The objective of this study was to identify the distribution of sandfly species, their density, and their habitats in the affected areas of leishmaniasis, southern Thailand. A cross-sectional survey of sandflies was conducted in three provinces of southern Thailand where leishmaniasis cases were previously reported. The collection of sandflies was performed using CDC light traps for four consecutive months, from March to June 2009. A total of 2,698 sandflies were collected in the affected areas. Among 1,451 female sandflies, six species of genus Sergentomyia were identified, i.e., Sergentomyia gemmea, Sergentomyia iyengari, Sergentomyia barraudi, Sergentomyia indica, Sergentomyia silvatica, and Sergentomyia perturbans. S. gemmea (81.4%) was the most predominant species in all areas. In addition, one species of the genus Phlebotomus, Phlebotomus argentipes, a known vector of leishmaniasis was also detected. The distribution of sandfly species in these leishmaniasis-affected areas was different from the previous studies in other areas of Thailand. Further studies are needed to proof whether these sandflies can be the natural vectors of leishmaniasis.

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Heterogeneity of Environments Associated with Transmission of Visceral Leishmaniasis in South-Eastern France and Implication for Control Strategies

BackgroundVisceral leishmaniasis due to Leishmania infantum is currently spreading into new foci across Europe. Leishmania infantum transmission in the Old World was reported to be strongly associated with a few specific environments. Environmental changes due to global warming or human activity were therefore incriminated in the spread of the disease. However, comprehensive studies were lacking to reliably identify all the environments at risk and thereby optimize monitoring and control strategy.Methodology/FindingsWe exhaustively collected 328 cases of autochthonous visceral leishmaniasis from 1993 to 2009 in South-Eastern France. Leishmaniasis incidence decreased from 31 yearly cases between 1993 and 1997 to 12 yearly cases between 2005 and 2009 mostly because Leishmania/HIV coinfection were less frequent. No spread of human visceral leishmaniasis was observed in the studied region. Two major foci were identified, associated with opposite environments: whereas one involved semi-rural hillside environments partly made of mixed forests, the other involved urban and peri-urban areas in and around the region main town, Marseille. The two neighboring foci were related to differing environments despite similar vectors (P. perniciosus), canine reservoir, parasite (L. infantum zymodeme MON-1), and human host.Conclusions/SignificanceThis unprecedented collection of cases highlighted the occurrence of protracted urban transmission of L. infantum in France, a worrisome finding as the disease is currently spreading in other areas around the Mediterranean. These results complete previous studies about more widespread canine leishmaniasis or human asymptomatic carriage. This first application of systematic geostatistical methods to European human visceral leishmaniasis demonstrated an unsuspected heterogeneity of environments associated with the transmission of the disease. These findings modify the current view of leishmaniasis epidemiology. They notably stress the need for locally defined control strategies and extensive monitoring including in urban environments.

Leishmania infantum and human visceral leishmaniasis, Argentina.

To the Editor: In Argentina, 14 autochthonous human cases of visceral leishmaniasis (VL) were reported during 1925–1989. These cases occurred in different localities in Salta, Jujuy, Santiago del Estero, and Chaco Provinces of northwestern Argentina (Figure A1), where cutaneous leishmaniasis (CL) caused principally by Leishmania (Viannia) braziliensis is endemic. It had been postulated that scattered/sporadic VL cases could be caused by visceralization of dermatrophic Leishmania spp. because of 1) absence of already recognized L. (Leishmania) infantum vector species; 2) geographic overlap with the region where CL is endemic; 3) simultaneous symptoms of CL; or 4) lack of detailed parasitic characterization at the molecular level for cases of suspected VL (1). However, during recent decades, urban outbreaks of VL have spread to southern regions of South America (Mato Grosso do Sul, Brazil, and Asuncion, Paraguay) near the northern border with Argentina. In May 2006, an autochthonous human case of VL was reported in Posadas (northeastern Argentina); it was associated with the canine visceral form of the disease. In addition, the presence of Lutzomyia longipalpis sandflies was also reported (2). Currently, 58 human VL cases have been reported in Posadas (3), and >7,000 infected dogs, Lu. longipalpis sandflies, and canine VL have been found 350 km south of Posadas (4). During 2007–2008, new VL cases in 4 children and 7 dogs were reported clustering in time and space in La Banda-Santiago del Estero in the dry Chaco region of Argentina. This focus showed a different pattern from that found in the only urban outbreak of VL reported (nearly the same number of cases in humans and dogs, and the suspected vector was Lu. migonei sandflies instead of Lu. longipalpis sandflies) (5). We report a case of autochthonous human VL in Salta Argentina that was caused by L. (L.) infantum. This parasite was characterized by cytochrome b (cytb) gene sequencing. Sequencing of this gene has been validated for precise characterization of Leishmania spp (6,7). On September 9, 2009, a 44-year-old man from Salta, Argentina (Figure A1), was admitted to the Infectious Disease Service at Hospital Senor del Milagro in Salta. The patient had fever, weight loss, dyspepsia, and splenomegaly that evolved over 3 weeks. Physical examination showed cutaneous and mucosal paleness. His general condition was feverish and rapidly deteriorating. Laboratory tests at the time of final diagnosis showed anemia, leukocytopenia, thrombocytopenia, and increased levels of lactate dehydrogenase. Results of urinalysis and coproculture were negative for parasites. Electrophoresis of serum proteins showed increased levels of gamma globulins. The differential diagnosis was negative for malaria, mycosis, autoimmune hepatitis, and lymphoma. A bone marrow smear showed abundant amastigotes by Giemsa staining (Figure, panel A). The patient was treated with liposomal amphotericin B, 3 mg/day for 7 days, and recovered (8). After a comprehensive interview, we verified that this patient had not been in the VL-endemic area in Argentina. However, he had worked (deforestation activities) during January–February 2009 on a farm in Finca Las Maravillas (22o3′29.30″S, 63o14′28.17″W), where he had been bitten by phlebotomines and acquired the disease. This farm was situated in the dry Chaco region near the border with Bolivia and Paraguay (zones with VL) (9), a region with intensive deforestation and agricultural activities. For species identification, DNA was extracted from a bone marrow aspirate and peripheral blood. We amplified by nested PCR and sequenced the cytb gene (Figure, panel B) (6). The aligned 817-bp sequence obtained showed 100% homology with the cytb gene of the MHOM/TN/80/IPT1 L. (L.) infantum World Health Organization reference strain (Tunisian strain) and 99.3% homology with the MHOM/BR/74/PP75 L. (L.) chagasi strain (Brazilian strain) (7). L. (L.) infantum was identified as the causative agent of this VL case in Salta, Argentina, where VL cases had not been seen for 50 years. Our findings indicate that this case was not caused by visceralization or a dermatropic Leishmania spp. We suggest that the scattered pattern of VL incidence in the dry Chaco region is caused by an enzootic cycle with accidental human transmission (5). There are no reports of Lu. longipalpis sandflies in the study area or surrounding areas (10). Nevertheless, studies on natural infections of vector sandflies and reservoir-host animals (especially dogs) are needed. Therefore, the search for naturally infected sandflies and reservoirs of this infection should be intensified. Epidemiologic surveys of dogs are needed to identify spread of VL foci in areas of deforestation. Deforestation could alter vector and reservoir range and parasite density in the enzootic cycle and increase human exposure to infected vectors. Figure Case of autochthonous human visceral leishmaniasis in a 44-year-old man, identified by parasitologic diagnosis and molecular detection of the causative species, Salta, Argentina. A) Leishmania amastigotes in a bone marrow smear. N, nucleus; K, kinetoplast; ...

Autochthonous visceral leishmaniasis in Brasília, Federal District, Brazil

Visceral leishmaniasis is a public health threat in Brazil considering the high lethality rates and increasing geographical dispersion to large urban conglomerates over the past 25 years. This study aimed to confirm suspected autochthonous cases of visceral leishmaniasis reported from 2005 to 2009 among individuals living in Brasilia, Federal District. A retrospective review of the surveillance data obtained on a regular basis and clinical records of the reported cases were performed in 2009. Data from entomological and canine surveys revealed the presence of both Lutzomyia longipalpis and positive serology for Leishmania in dogs within 19 of the 21 neighborhoods where human cases occurred since 2005. The review of surveillance data and medical records, together with the entomological and canine survey data, permitted confirmation of 21 autochthonous human cases in the Federal District. The disease predominantly affected children (12/21) and those from the Sobradinho region (16/21); the typical presentation of fever, hepatosplenomegaly and pancytopenia was observed in 67% of cases. Three deaths occurred during the study period. Leishmania (Leishmania) chagasi was successfully isolated from one human case and twelve canine cases. Visceral leishmaniasis should be considered endemic in Brasilia based on the documented epidemiological behavior herein described and the confirmed autochthony of human cases.

American visceral leishmaniasis dissociated from Lutzomyia longipalpis (Diptera, Psychodidae) in the State of Espírito Santo, Brazil

The occurrence of American visceral leishmaniasis in the State of Espírito Santo, Brazil has always been associated with the presence of the Lutzomyia longipalpis vector. The geographic distribution of this vector in this state is related to the presence of specific geoclimatic characteristics, such as a dry climate, low elevations (< 450 m), steep slopes and rocky outcrops. The occurrence of human autochthonous cases of American visceral leishmaniasis in municipalities without these geoclimatic characteristics justifies the present study and our main goal was to test the association between the occurrence of American visceral leishmaniasis and the presence of the Lu. longipalpis. Sand flies were captured monthly from July 2006 to August 2007 using Shannon and CDC traps in two municipalities with records of autochthonous American visceral leishmaniasis and one with no record. We captured 13,112 sand flies, but no Lu. longipalpis was found. The absence of Lu. longipalpis and the possible role of another American visceral leishmaniasis vector in these localities were discussed.