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Sandflies are known vectors of leishmaniasis. In the Old World, sandflies are also vectors of viruses while little is known about the capacity of New World insects to transmit viruses to humans. Here, we relate the identification of RNA sequences with homology to rhabdovirus nucleocapsids (NcPs) genes, initially in the Lutzomyia longipalpis LL5 cell lineage, named NcP1.1 and NcP2. The Rhabdoviridae family never retrotranscribes its RNA genome to DNA. The sequences here described were identified in cDNA and DNA from LL-5 cells and in adult insects indicating that they are transcribed endogenous viral elements (EVEs). The presence of NcP1.1 and NcP2 in the L. longipalpis genome was confirmed in silico. In addition to showing the genomic location of NcP1.1 and NcP2, we identified another rhabdoviral insertion named NcP1.2. Analysis of small RNA molecules derived from these sequences showed that NcP1.1 and NcP1.2 present a profile consistent with elements targeted by primary piRNAs, while NcP2 was restricted to the degradation profile. The presence of NcP1.1 and NcP2 was investigated in sandfly populations from South America and the Old World. These EVEs are shared by different sandfly populations in South America while none of the Old World species studied presented the insertions.

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Molecular methods have been responsible for a notable increase in the detection of Leishmaniinae infections in wild animals. Determining their infectiousness is of paramount importance in evaluating their epidemiological significance. One of the most efficient ways of determining infectiousness for vector borne diseases is xenodiagnosis with the appropriate vector. However, this is logistically very difficult to accomplish in the field, and an ideal solution is to find a molecular surrogate for xenodiagnosis. In this review we discuss different approaches to the problem by focusing on the infectiousness of Leishmania (Viannia) braziliensis in rodents under laboratory and field conditions. Comparisons with similar studies for other Leishmania species emphasizes that there are pivotal differences in the infectiousness and the importance of asymptomatic infections in different hosts. Potentially the most promising surrogate is the real time quantitative PCR (qPCR). However, its success depends on choosing a tissue that relates to the vector's feeding location and the parasite's tissue tropism. This requires detailed knowledge of the infection of each species in its wild hosts. We conclude that for L. (V.) braziliensis infections in wild rodents the tissue of choice for a molecular xenodiagnostic test, based on the qPCR is blood, providing that a significant number of samples must be examined.

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BACKGROUND: Human and wild rodent infection rates with Leishmania (Viannia) braziliensis are needed to differentiate transmission pathways in anthropogenically altered habitats. METHODS: Human participants in northeast Brazil were tested by the leishmanin skin test (LST) and inspected for lesions/scars characteristic of American clinical leishmaniasis (ACL). Molecular (PCR/qPCR) test records of free-ranging rodents were available from a concurrent capture-mark-recapture study. Force of Infection (λ) and recovery (ρ) rates were estimated from cross-sectional and longitudinal datasets. RESULTS: Cumulative prevalences of human LST+ves and ACL scar+ves were 0.343-0.563 (n = 503 participants) and 0.122-0.475 (n = 503), respectively. Active ACL lesions were not detected. Annual rates of LST conversions were λ = 0.03-0.15 and ρ = 0.02-0.07. The probability of infection was independent of sex and associated with increasing age in addition to the period of exposure. Rodents (n = 596 individuals of 6 species) showed high rates of exclusively asymptomatic infection (λ = 0.222/month) and potential infectiousness to the sand fly vector. Spatially concurrent rodent and household human infection prevalences were correlated. CONCLUSIONS: Human exposure to L. (V.) braziliensis continues to be high despite the substantial drop in reported ACL cases in recent years. Spill-over transmission risk to humans from rodents in peridomestic habitats is likely supported by a rodent infection/transmission corridor linking houses, plantations, and the Atlantic Forest.

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ABSTRACT Molecular methods have been responsible for a notable increase in the detection of Leishmaniinae infections in wild animals. Determining their infectiousness is of paramount importance in evaluating their epidemiological significance. One of the most efficient ways of determining infectiousness for vector borne diseases is xenodiagnosis with the appropriate vector. However, this is logistically very difficult to accomplish in the field, and an ideal solution is to find a molecular surrogate for xenodiagnosis. In this review we discuss different approaches to the problem by focusing on the infectiousness of Leishmania (Viannia) braziliensis in rodents under laboratory and field conditions. Comparisons with similar studies for other Leishmania species emphasizes that there are pivotal differences in the infectiousness and the importance of asymptomatic infections in different hosts. Potentially the most promising surrogate is the real time quantitative PCR (qPCR). However, its success depends on choosing a tissue that relates to the vector's feeding location and the parasite's tissue tropism. This requires detailed knowledge of the infection of each species in its wild hosts. We conclude that for L. (V.) braziliensis infections in wild rodents the tissue of choice for a molecular xenodiagnostic test, based on the qPCR is blood, providing that a significant number of samples must be examined.

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Leishmaniases are neglected tropical diseases and Leishmania (Leishmania) infantum and Leishmania (Viannia) braziliensis are the most important causative agents of leishmaniases in the New World. These two parasite species may co-circulate in a given endemic area but their interactions in the vector have not been studied yet. We conducted experimental infections using both single infections and co-infections to compare the development of L. (L.) infantum (OGVL/mCherry) and L. (V.) braziliensis (XB29/GFP) in Lutzomyia longipalpis and Lutzomyia migonei. Parasite labelling by different fluorescein proteins enabled studying interspecific competition and localization of different parasite species during co-infections. Both Leishmania species completed their life cycle, producing infective forms in both sand fly species studied. The same happens in the co infections, demonstrating that the two parasites conclude their development and do not compete with each other. However, infections produced by L. (L.) infantum reached higher rates and grew more vigorously, as compared to L. (V.) braziliensis. In late-stage infections, L. (L.) infantum was present in all midgut regions, showing typical suprapylarian type of development, whereas L. (V.) braziliensis was concentrated in the hindgut and the abdominal midgut (peripylarian development). We concluded that both Lu. migonei and Lu. longipalpis are equally susceptible vectors for L. (L.) infantum, in laboratory colonies. In relation to L. (V.) braziliensis, Lu. migonei appears to be more susceptible to this parasite than Lu. longipalpis.

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Cutaneous leishmaniasis (CL) by Leishmania braziliensis Vianna (Kinetoplastida: Trypanosomatidae) is a widespread disease in the western hemisphere and Brazil is the country reporting the majority of the human cases each year. Several phlebotomine sand flies have been regarded as putative or proven vectors of L. braziliensis and multiple vectors may be involved in the transmission of this parasite in the same endemic foci. In this study, we tested a subset of female phlebotomine sand flies collected in the frame of a previous study conducted in a military training camp, where outbreaks of CL by L. braziliensis have sporadically been reported. In total, 1,807 female phlebotomine sand flies were tested (individually or in pools) by real-time PCR and a minimum infection rate of 0.9% (95% CI: 0.6-1.5%) was detected. Positive females belonged to the species Psychodopygus complexus (Mangabeira) or Psychodopygus wellcomei Fraiha, Shaw & Lainson (females of these species are morphologically indistinguishable), Trichopygomyia longispina (Mangabeira), and Sciopemyia sordellii (Shannon & Del Ponte) (Diptera: Psychodidae). By restriction enzyme analysis, 13 samples (nine of Ty. longispina, two of Ps. complexus/wellcomei, and two of Sc. sordellii) presented a HaeIII restriction profile identical to L. braziliensis. The results of this study reinforce the notion that multiple vectors may be involved in the transmission of L. braziliensis in a single focus, ultimately making the epidemiological picture more complex than currently recognized.

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Leishmania braziliensis, the main etiological agent of cutaneous leishmaniasis (CL) in Latin America, is characterized by major differences in basic biology in comparison with better-known Leishmania species. It is also associated with a high phenotypic and possibly genetic diversity that need to be more adequately defined. Here we used whole genome sequences to evaluate the genetic diversity of ten L. braziliensis isolates from a CL endemic area from Northeastern Brazil, previously classified by Multi Locus Enzyme Electrophoresis (MLEE) into ten distinct zymodemes. These sequences were first mapped using the L. braziliensis M2904 reference genome followed by identification of Single Nucleotide Polymorphisms (SNPs). A substantial level of diversity was observed when compared with the reference genome, with SNP counts ranging from ~95,000 to ~131,000 for the different isolates. When the genome data was used to infer relationship between isolates, those belonging to zymodemes Z72/Z75, recovered from forested environments, were found to cluster separately from the others, generally associated with more urban environments. Among the remaining isolates, those from zymodemes Z74/Z106 were also found to form a separate group. Phylogenetic analyses were also performed using Multi-Locus Sequence Analysis from genes coding for four metabolic enzymes used for MLEE as well as the gene sequence coding for the Hsp70 heat shock protein. All 10 isolates were firmly identified as L. braziliensis, including the zymodeme Z26 isolate previously classified as Leishmania shawi, with the clustering into three groups confirmed. Aneuploidy was also investigated but found in general restricted to chromosome 31, with a single isolate, from zymodeme Z27, characterized by extra copies for other chromosomes. Noteworthy, both Z72 and Z75 isolates are characterized by a much reduced heterozygosity. Our data is consistent with the existence of distinct evolutionary groups in the restricted area sampled and a substantial genetic diversity within L. braziliensis.

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BACKGROUND: The possibility that a multi-host wildlife reservoir is responsible for maintaining transmission of Leishmania (Viannia) braziliensis causing human cutaneous and mucocutaneous leishmaniasis is tested by comparative analysis of infection progression and infectiousness to sandflies in rodent host species previously shown to have high natural infection prevalences in both sylvatic or/and peridomestic habitats in close proximity to humans in northeast Brazil. METHODS: The clinical and parasitological outcomes, and infectiousness to sandflies, were observed in 54 colonized animals of three species (18 Necromys lasiurus, 18 Nectomys squamipes and 18 Rattus rattus) experimentally infected with high (5.5 × 10(6)/ml) or low (2.8 × 10(5)/ml) dose L. (V.) braziliensis (MBOL/BR/2000/CPqAM95) inoculum. Clinical signs of infection were monitored daily. Whole animal xenodiagnoses were performed 6 months post inoculation using Lutzomyia longipalpis originating from flies caught in Passira, Pernambuco, after this parasite evaluation was performed at necropsy. Heterogeneities in Leishmania parasite loads were measured by quantitative PCR in ear skin, liver and spleen tissues. RESULTS: All three rodent species proved to establish infection characterized by short-term self-resolving skin lesions, located on ears and tail but not on footpads (one site of inoculation), and variable parasite loads detected in all three tissues with maximum burdens of 8.1 × 10(3) (skin), 2.8 × 10(3) (spleen), and 8.9 × 10(2) (liver). All three host species, 18/18 N. lasiurus, 10/18 N. squamipes and 6/18 R. rattus, also proved infectious to sandflies in cross-sectional study. R. rattus supported significantly lower tissue parasite loads compared to those in N. lasiurus and N. squamipes, and N. lasiurus appeared to be more infectious, on average, than either N. squamipes or R. rattus. CONCLUSIONS: A multi-host reservoir of cutaneous leishmaniasis is indicated in this region of Brazil, though with apparent differences in the competence between the rodent species. The results provide preliminary insights into links between sylvatic and peri-domestic transmission cycles associated with overlaps in the rodent species' ecological niches.

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BACKGROUND: Leishmania parasites cause leishmaniasis in humans and animals worldwide. These parasites are transmitted by phlebotomine sand flies, which become infected upon feeding on an infected mammalian host. We assessed the occurrence of Leishmania infection in small mammals in an area of cutaneous and visceral leishmaniasis endemicity. METHODS: A total of 180 small mammals were trapped in 2003 and 2006 in a rural area in north-eastern Brazil. Spleen and skin samples from these animals were assessed by two PCR protocols, one targeting Leishmania (Viannia) spp. and other Leishmania (Leishmania) infantum. Additionally, serum samples were tested by an immunochromatographic test with rK39 as antigen. RESULTS: Overall, 23.2% (38/164) of the animals were positive to L. (V.) spp. and 8.8% (14/160) to L. (L.) infantum). Five animals of four species (Didelphis albiventris, Nectomys squamipes, Rattus rattus and Holochilus sciureus) were positive by both PCR protocols, an overall co-infection rate of 2.5%. By serology, 5% (7/139) of the animals were positive, but all of them were PCR-negative. An isolate obtained from a water rat (N. squamipes) was characterized as L. (V.) braziliensis (zymodeme Z-74). CONCLUSIONS: This study reinforces the involvement of different small mammals (e.g., N. squamipes, R. rattus and H. scieurus) in the transmission cycles of L. (V.) braziliensis and L. (L.) infantum in north-eastern Brazil. The finding of L. (V.) braziliensis infection in black rats suggests a rapid process of adaptation of a New World Leishmania species to an Old World rodent and raises interesting questions regarding the co-evolution of these parasites and their vertebrate hosts.

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Approximately 800 species of phlebotomine sand flies, many of which are vectors of Leishmania, have been described. Besides morphological similarities within groups, the occurrence of anomalies within a species may lead to an erroneous description of new species. This paper describes one phlebotomine sand fly, Evandromyia evandroi, with a symmetrical bilateral anomaly in the number of spines on the gonostyle. In this specimen, the anomalous spine is located in the external region of gonostyle, inserted between the upper external and the lower external spines. It is important to document morphological anomalies, so as to avoid erroneous sand fly identifications.

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The purpose of this study is to analyze the spatial distribution and population trends through time of Lutzomyia species in a long-term focus of cutaneous leishmaniasis transmission in an Atlantic Forest area, northeastern Brazil. Sand fly populations of different ecological niches were monitored spatiotemporally in 2009. To summarize vegetation characteristics and phenology, we calculated the Normalized Difference Vegetation Index from Landsat images. Using niche modeling approaches, we assessed suites of environmental factors to identify areas of transmission risk. Although 12 species were detected, L. whitmani was the most abundant and broadly distributed across the area, particularly in peridomiciliary locations, and associated negatively with denser vegetation areas. On the other hand, L. complexa, L. sordelli, and L. tupynambai were found almost exclusively in forested areas (P < 0.05), and associated positively with denser vegetation. Lutzomyia species' occurrences are related to specific environmental combinations (with contrast among species) in the region.

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Sand fly populations of different ecological niches in the Amaraji endemic American Cutaneous Leishmaniasis (ACL) focus of the Pernambuco Atlantic Forest region of northeastern Brazil were monitored spatiotemporally. Lutzomyia whitmani was dominant in all niches but occurred in smaller numbers in forested locations. L. whitmani was significantly less seasonal than the other species, being present throughout the year while other species were more abundant between February and April. These results suggest that L. whitmani may potentially be the principal vector of ACL in the region, even though the sand fly fauna was diverse: 88% were L.whitmani and 12% belonged to 11 other species. Two other species, L. complexa (1.3%) and L. migonei (0.8%), considered to be ACL vectors in other regions, were also present. This detailed picture of the sand fly population's abundance and spatiotemporal distribution provides a basis for future modeling studies of forecasting sand fly activity patterns and ACL occurrence.

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A community-based epidemiological study was carried out in a rural area in northeastern Brazil, where visceral leishmaniasis is endemic, but the primary vector Lutzomyia longipalpis has never been found. Forty-one dogs were screened by an indirect immunofluorescence antibody test (IFAT) for the presence of anti-Leishmania antibodies and 12 (29.3%) of them were positive. One of the IFAT-positive dogs was also positive for Leishmania amastigotes in bone marrow cytology and for Leishmania infantum by real-time polymerase chain reaction (PCR) on blood. One IFAT-negative dog was positive for L. infantum by PCR on bone marrow and other for Leishmania amastigotes in skin stained-smears. When tested for L. braziliensis by PCR, 20 dogs were positive. Considering all diagnostic tests, the estimated prevalence of Leishmania spp. infection in the studied rural dog population was 58.5%. There was no significant difference in IFAT-positivity in relation to age, gender, and clinical status of the dogs. When tested for L. infantum by real-time PCR, 20 ticks collected from IFAT-positive dogs were all negative. This study shows a high level of exposure to Leishmania spp. infection in dogs from a rural community in northeastern Brazil. In general, the results do not support the participation of ticks as vectors of L. infantum in this area, which is likely to be transmitted by Lutzomyia spp. other than L. longipalpis. Finally, this study highlights that the use of IFAT in areas where both L. infantum and L. braziliensis are present should be withdraw in order to avoid the unnecessary culling of dogs that are actually infected only by L. braziliensis.

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Canine leishmaniosis is a widespread disease caused by Leishmania parasites, which are transmitted by phlebotomine sand flies. However, in some areas where canine leishmaniosis is endemic, but the primary vectors have not been found, ticks have been suspected to play a role in transmitting the infection. Herewith, we report the detection of Leishmania infantum kinetoplast minicircle DNA (kDNA) in ticks collected from naturally infected dogs living in rural areas of Southern Italy (site A) and Northeastern Brazil (site B). Between March and October 2007, ticks were collected from 26 dogs positive to anti-Leishmania antibodies (one from site A and 25 from site B) and either placed directly into vials containing 70% ethanol or maintained alive for identification and subsequent dissection. All the 95 ticks collected were morphologically identified as Rhipicephalus sanguineus. After identification, their genomic DNA was extracted (either individually or in pools) and processed by polymerase chain reaction (PCR) for the detection of L. infantum kDNA. Two pools of salivary glands from ticks (one from five females and other from five males) found on a dog from site A and tested by a conventional PCR were positive. Amplicon sequencing confirmed the identity of the parasite. In addition, nine (12.3%) out of the 73 ticks found on dogs from site B and tested by a real-time PCR were positive, with a low parasite load (less than 1 parasite/ml). The retrieval of L. infantum kDNA in salivary glands of R. sanguineus ticks has been here reported for the first time. Therefore, further studies are needed to assess the competence of ticks as vectors of Leishmania parasites from dog to dog.

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A group of 18 research workers involved in different aspects of the biology of Lutzomyia longipalpis discussed whether or not it is important to give taxonomically valid names to populations that have been defined by biological, biochemical and molecular methods to be reproductively isolated. The type material of this medically important species has been lost and because of this it was recommended that a colony should be established from insects captured in the region of the type area and that their description should serve as the basis for future descriptions. It was pointed out that there is a lack of uniformity in the naming of closely related American sand flies and that some of the differences between populations of Lu. longipalpis are greater than those between accepted species. The majority of the participants agreed that the populations that have been defined in the literature as sibling species should be named.

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This article presents the results of a study on ectoparasites infesting rural dogs in Pernambuco, northeastern Brazil. Forty-one dogs from a rural community of Pernambuco were examined and 70.7% were infested by ectoparasites. The prevalence rates of infestation by ticks, fleas, and lice were 58.5, 43.9 and 22%, respectively. Of 24 dogs parasitized by ticks, 15 were exclusively infested by Rhipicephalus sanguineus (Latreille) (32 females, 66 males, 9 nymphs; prevalence, 48.8%; mean intensity, 5.4), four by Amblyomma ovale Koch (33 females, 19 males; prevalence, 22%; mean intensity, 5.8), and five were coinfested by both species. Ctenocephalides felis felis (Bouché) (25 females, 8 males; prevalence, 43.9%; mean intensity, 1.9) and Heterodoxus spiniger (Enderlein) (16 females, 11 males, 10 nymphs; prevalence, 22%; mean intensity, 4.1) were the only species of flea and louse identified. Tick infestation was more frequent than flea or lice infestations (p < 0.05). No statistical difference was found by sex and age group of the dogs studied and prevalence of infestation. Overall, 48.8% (20/41) of the dogs were infested by more than one ectoparasite species.

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This article presents the results of a study on ectoparasites infesting rural dogs in Pernambuco, northeastern Brazil. Forty-one dogs from a rural community of Pernambuco were examined and 70.7 percent were infested by ectoparasites. The prevalence rates of infestation by ticks, fleas, and lice were 58.5, 43.9 and 22 percent, respectively. Of 24 dogs parasitized by ticks, 15 were exclusively infested by Rhipicephalus sanguineus (Latreille) (32 females, 66 males, 9 nymphs; prevalence, 48.8 percent; mean intensity, 5.4), four by Amblyomma ovale Koch (33 females, 19 males; prevalence, 22 percent; mean intensity, 5.8), and five were coinfested by both species. Ctenocephalides felis felis (Bouché) (25 females, 8 males; prevalence, 43.9 percent; mean intensity, 1.9) and Heterodoxus spiniger (Enderlein) (16 females, 11 males, 10 nymphs; prevalence, 22 percent; mean intensity, 4.1) were the only species of flea and louse identified. Tick infestation was more frequent than flea or lice infestations (p < 0.05). No statistical difference was found by sex and age group of the dogs studied and prevalence of infestation. Overall, 48.8 percent (20/41) of the dogs were infested by more than one ectoparasite species.

O presente artigo apresenta os resultados de um estudo sobre os ectoparasitos que infestam cães rurais em Pernambuco, Nordeste do Brasil. Quarenta e um cães de uma comunidade rural de Pernambuco foram examinados e 70,7 por cento estavam infestados por ectoparasitos. As taxas de prevalência de infestação por carrapatos, pulgas e piolhos foram 58,5, 43,9 e 22 por cento, respectivamente. Dos 24 cães parasitados por carrapatos, 15 estavam exclusivamente infestados por Rhipicephalus sanguineus (Latreille) (32 fêmeas, 66 machos, 9 ninfas; prevalência, 48,8 por cento; intensidade média, 5,4), quatro por Amblyomma ovale Koch (33 fêmeas, 19 machos; prevalência, 22 por cento; intensidade média, 5,8), e cinco estavam co-infestados por ambas as espécies. Ctenocephalides felis felis (Bouché) (25 fêmeas, 8 machos; prevalência, 43,9 por cento; intensidade média, 1,9) e Heterodoxus spiniger (Enderlein) (16 fêmeas, 11 machos, 10 ninfas; prevalência, 22 por cento; intensidade média, 4,1) foram as únicas espécies de pulga e piolho identificadas. A infestação por carrapatos foi mais frequente que as infestações por pulgas ou piolhos (p < 0.05). Não houve diferença estatística em relação ao sexo e grupo etário dos cães e a prevalência de infestação. No geral, 48,8 por cento (20/41) dos cães estavam infestados por mais de uma espécie de ectoparasito.

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OBJECTIVES: To identify the aetiological agents of cutaneous leishmaniasis and to investigate the genetic polymorphism of Leishmania (Viannia) parasites circulating in an area with endemic cutaneous leishmaniasis (CL) in the Atlantic rainforest region of northeastern Brazil. METHODS: Leishmania spp. isolates came from three sources: (i) patients diagnosed clinically and parasitologically with CL based on primary lesions, secondary lesions, clinical recidiva, mucocutaneous leishmaniasis and scars; (ii) sentinel hamsters, sylvatic or synanthropic small rodents; and (iii) the sand fly species Lutzomyia whitmani. Isolates were characterised using monoclonal antibodies, multilocus enzyme electrophoresis (MLEE) and polymerase chain reaction-restriction fragment length polymorphism of the internal transcribed spacer region rDNA locus. RESULTS: Seventy-seven isolates were obtained and characterised. All isolates were identified as Leishmania (Viannia) braziliensis serodeme 1 based on reactivity to monoclonal antibodies. MLEE identified 10 zymodemes circulating in the study region. Most isolates were classified as zymodemes closely related to L. (V.) braziliensis, but five isolates were classified as Leishmania (Viannia) shawi. All but three of the identified zymodemes have so far been observed only in the study region. Enzootic transmission and multiclonal infection were observed. CONCLUSIONS: Our results confirm that transmission cycle complexity and the co-existence of two or more species in the same area can affect the level of genetic polymorphism in a natural Leishmania population. Although it is not possible to make inferences as to the modes of genetic exchange, one can speculate that some of the zymodemes specific to the region are hybrids of L. (V.) braziliensis and L. (V.) shawi.

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A group of 18 research workers involved in different aspects of the biology of Lutzomyia longipalpis discussed whether or not it is important to give taxonomically valid names to populations that have been defined by biological, biochemical and molecular methods to be reproductively isolated. The type material of this medically important species has been lost and because of this it was recommended that a colony should be established from insects captured in the region of the type area and that their description should serve as the basis for future descriptions. It was pointed out that there is a lack of uniformity in the naming of closely related American sand flies and that some of the differences between populations of Lu. longipalpis are greater than those between accepted species. The majority of the participants agreed that the populations that have been defined in the literature as sibling species should be named.

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This study aimed to demonstrate the geographical expansion of visceral leishmaniasis in Pernambuco State, Brazil. With data on the number of visceral leishmaniasis cases notified from 1990 to 2001, maps showing the biannual evolution of the geographical distribution of the disease per municipality were elaborated. A map of the cumulative geographical distribution of the cases registered during the whole period was also constructed. From 1990 to 2001, 1,737 cases of visceral leishmaniasis were notified in Pernambuco. In 1990, 15.2% (n = 28) of the municipalities notified cases of the disease. In contrast, this percentage increased to 78.3% (n = 144), over an eleven-year period. The map of cumulative geographical distribution during the whole period shows a notable concentration of cases in Agreste and Sertão. A notable geographical expansion of visceral leishmaniasis in Pernambuco also occurred, probably reflecting the low impact of the current control measures and, possibly, an improvement in the notification system.

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