Leishmaniasis In Endemic Area Research Articles

Leishmaniasis vectors in the environment of treated leishmaniasis cases in Spain.

Transmission of leishmaniasis in endemic areas is characterized by microfocality related to the presence of the vector. Most entomological studies in southwestern Europe have focused on sylvatic areas and town outskirts, very few have sampled town or urban centres, and no survey has investigated inside households. The aim of this study was to determine the sand fly species diversity and vector density in the surroundings of human leishmaniasis cases compared with environments in which there was no association. Sand flies were captured in 26 households associated with recently treated leishmaniasis patients, 15 neighbouring houses without associated cases, and in others environments. Overall 7495 sand flies belonging to six species were captured. The highest sand fly density was found in farmhouses where there is a great availability of blood sources and breeding sites. In the environment of human leishmaniasis cases, Sergentomyia minuta was the most prevalent species followed by Phlebotomus perniciosus. Nevertheless, lower Leishmania infantum infection rates and lower intensity of infection were detected in S. minuta sand flies than in P. perniciosus. The density of P. perniciosus in households with recently treated leishmaniasis patients varies between 0 and 108 sand flies per light trap/night, with the maximum values corresponding to farmhouses. This species appears to be adapted to both indoors and outdoors domestic biotopes, including urban households.

Blood Meal Analysis and Molecular Detection of Leishmania DNA in Wild-Caught Sand Flies in Leishmaniasis Endemic Areas of Turkey and Northern Cyprus.

Phlebotomine sand flies (Diptera: Psychodidae) are known as the vector of diseases such as leishmaniasis, bartonellosis and viral diseases. The aim of this study is to detect the host feeding pattern of sand flies in the endemic areas for leishmaniasis in Turkey (Antalya, Kayseri) and Northern Cyprus (TRNC) as well as the presence of Leishmania DNA in the specimens. One-hundred seventy-six blood-fed sand fly specimens were examined for blood meal analysis. A SYBR Green-PCR assay was performed with specific forward primers for each host and a universal reverse primer. Primers of human and goat were used together in multiplex PCR while goat and cow were studied separately. ITS-1 qPCR assay was also performed on both blood-fed and non-blood-fed females to detect Leishmania parasites. Blood sources could be detected in 69 out of 176 blood-fed sand fly specimens. The results of blood meal analysis showed that specimens were fed mostly on cows (22.2%) followed by humans (5.7%), goats (2.8%) and dogs (0.6%). Multiple feeding patterns were also detected as human + cow (3.4%), cow + goat (2.8%) and human + goat (1.7%). Five of the blood-fed specimens were Leishmania spp. positive: P. major s.l. (n = 1), P. tobbi (n = 2) were L. tropica positive from Antalya, P. simici was positive for L. infantum from Kayseri and P. papatasi (n = 1) was positive for L. major from Cyprus. Leishmania infection rates were determined as 3.79%, 1.69% and 2.63% among the blood-fed sand fly specimens in Antalya, Kayseri and TRNC, respectively. The SYBR-Green-based multiplex PCR assay is a cost-effective and promising tool for blood meal identification of wild-caught sand flies as well as other blood-sucking arthropods. Feeding patterns of important vector species detected in the present study show the high risk in these endemic areas. As a next step, to identify the blood source in a shorter time and to make the test more sensitive, development of this assay to probe-based and multiplex PCR will be also planned.

Leishmaniasis in wild, synanthropic and domestic animals on the Island of Itamaracá, Pernambuco, Northeastern Brazil

Leishmaniasis are notifiable diseases, characterized by severe clinical manifestations, being caused by obligate intracellular protozoa, belonging to the genus Leishmania, where the species L. (L.) infantum and L. (V.) braziliensis are responsible for most cases. of leishmaniasis in Brazil. Many studies indicate the need for investigations into the exact role of animal species in the epidemiology of leishmaniasis, particularly of skunks and rodents, where the presence of these animals increases the chances of humans and other animals becoming infected. Considering the scarcity of information on the epidemiology of leishmaniasis in some regions of the State of Pernambuco, the objective of this study was to evaluate the occurrence of infection by Leishmania spp. in wild, synanthropic and domestic animals. For this, the parasitological diagnosis was carried out through exfoliative cytology of the skin of cutaneous lesions, in addition to PCR of the L. donovani and L. braziliensis complex of blood and spleen, liver and skin biopsy of rodents and skunks captured in an endemic area for leishmaniasis in the state of Pernambuco. In the locations where synanthropic animals positive for Leishmania were captured, blood, skin, bone marrow and lymph nodes were collected from the canine population. As a result, amastigote forms and DNA from the L. donovani complex were detected in 8.3% (2/24) of synanthropic animals (D. albiventris and O. nigripes). In the canine population, 29.4% (15/51) of dogs reactive for Visceral Leishmaniasis, and 6.6% were parasitologically and molecularly positive for the L. donovani complex. Thus, it is concluded that skunks, rodents and dogs participate in the transmission cycle of the L. donovani complex.

Identification of Toscana virus in natural population of sand flies (Diptera: Psychodidae) from Moroccan leishmaniasis foci

BackgroundPhlebotomine sand flies are known as vectors of various pathogens such as Leishmania sp parasite and Toscana virus (TOSV). Leishmaniasis is endemic in Morocco, and TOSV is increasingly reported. Our objective is to analyze the specific composition of the natural population of sand flies in endemic and non endemic area of leishmaniasis in Morocco, thus evaluated their infection by Toscana virus. MethodsSand flies were collected by CDC miniature light traps from seven different localities with an altitude range from 399 m to 1496 m. Synanthropic index was calculated for each sand fly species. The collected female sand flies were grouped in 73 pools, with a maximum of 50 specimens per pool, and submitted to real time PCR for TOSV detection. Results8 sand fly species were identified morphologically: 5 of the Phlebotomus genus and 3 of the Sergentomyia genus. Phlebotomus sergenti was the most abundant species comprising of 43,12% of identified sand flies, followed by P. papatasi (18,89%) and P. longicuspis (13,43%). Estimated synanthropic indices for these species were between + 1.1 and + 12.6 suggesting a high preference to anthropogenic environments. A total of 3558 sand fly females were grouped in 73 pools (up to 50 sand flies per pool) for TOSV detection. TOSV was detected in one pool (out of 6 tested) from Lalla Laaziza locality (Chichaoua Province) where P. sergenti was the most abundant sand fly species. ConclusionWe reported the TOSV for the first time in a central Morocco, where cutaneous leishmaniasis by L. tropica is endemic. This result has epidemiological importance for both researchers and health authorities to monitor circulation of TOSV and implement a surveillance plan of sand fly-borne phleboviruses in Morocco.

Population dynamics of phlebotomine sand flies (Diptera: Psychodidae) in cutaneous leishmaniasis endemic areas of Kurunegala District, Sri Lanka

Sand flies are the primary vectors of leishmaniasis. Disease management with effective vector control depends on the knowledge of vector population dynamics. In Sri Lanka, despite few isolated entomological collections, long-term studies are not reported to date. In the reported study, monthly entomological surveillance was conducted from May 2017 to December 2018 in Polpithigama, Maho, and Galgamuwa Medical Officer of Health (MOH) areas using standard entomological techniques. Climatic data were collected from the Department of Meteorology, Sri Lanka. Patient records were collected from each MOH office. A total of 38,339 sand flies were collected. The majority were Phlebotomus argentipes (99.50%, n = 38,147), while the rest was Sergentomyia punjabensis (0.50%, n = 192). Wind speed reduces sand fly abundance (r = -0.519, P < 0.05) evidently by limiting the movement. Rainfall increases sand fly abundance (r = 0.842, P <0.05, lag = 6 months) probably by improving favorable conditions in breeding sites. The actual effect of humidity is not conclusive without further research. The observed higher prevalence of leishmaniasis in the study sites could be due to the higher sand fly density in these areas. The number of patients shows a strong positive correlation (r = 0.516, P <0.05) to the sand fly abundance with a lag of 7 months. Systematic surveillance of sand flies as a part of general healthcare services is strongly recommended to identify and prevent possible outbreaks through timely planned vector control measures.

Fauna, Seasonal Activity, and Altitudinal Distribution of Phlebotomine Sand Flies (Diptera: Psychodidae) in Leishmaniasis Endemic Area, Aydın Mountains, and Surroundings in Western Turkey

Human and canine leishmaniasis (CanL) are endemic in Turkey, and cutaneous leishmaniasis (CL) is a primary public health problem among vector-borne diseases, with 1500-2000 autochthonous cases per year. In this study, we aimed to perform a comprehensive entomological survey, including the detection of sand fly fauna, seasonal activity, and altitudinal distribution, together with the ecological features of Aydın Mountains and their surroundings that are endemic areas for CL caused by Leishmania tropica and CanL caused by L. infantum MON-1. The survey was carried out from June 2009 to July 2010. Ten localities with different altitudes were selected. Sand fly collection was done every 15 days in July and August when sand flies are most active and every 30 days between September and June (14 months, 16 samplings) using CDC light traps and sticky traps. During the collection, the temperature, humidity, and ecological and environmental features were recorded. Sand fly specimens were dissected and identified at species level using written keys. A total of 6712 sand fly specimens (3268 females and 3444 males) were collected from 10 localities throughout all study periods. Species identification revealed that nine and three species belonging to Phlebotomus (P. major s.l. 30.38%, P. tobbi 22.93%, P. papatasi 5.88%, P. sergenti s.l. 4.51%, P. alexandri 4.26%, P. simici 3.50%, P. burneyi 0.63%, P. brevis 0.45%, and Transphlebotomus spp. 0.28%) and Sergentomyia (S. dentata 23.17%, S. minuta 2.43%, and S. antennata 1.58%) were found, respectively. The seasonal activities of these 12 sand fly species were determined, and P. major s.l. and P. tobbi, which were probable vectors of VL and CanL, were present in the study area. P. sergenti s.l., a probable vector of CL, was also found in the region and was active for seven months between April and October. P. sergenti s.l. was found in the 400-600 m altitude in July, while P. major and P. tobbi were found in high densities in the 200-400 m altitude in September. Our results showed that leishmaniasis vectors are present in different altitudes in the Aydın mountains and surroundings. The findings revealed the time intervals of parasite transmission in the area and the period of applying protective measures, such as insecticide application.

Detection of Wolbachia and Leishmania DNA in sand flies (Diptera: Psychodidae, Phlebotominae) from a focus of cutaneous leishmaniasis in Tabasco, Mexico.

Phlebotomine sand flies are the main vectors of Leishmania genus species worldwide; therefore, the detection of some reproductive parasites, such as Wolbachia, has been considered a possible strategy for biological control. In Mexico, leishmaniasis cases have been recorded in 25 states, yet only two sand fly species have been related to Wolbachia spp. Although the state of Tabasco has a high number of leishmaniasis cases, only few studies have been done on sand fly species. The aim of this study was to analyze the diversity of sand fly species and to detect Wolbachia spp. and/or Leishmania spp. in the captured specimens. Sand flies were collected at the locality of Huimango, Tabasco, Mexico, during October 2019, using nine light traps (CDC) and two Shannon traps per night. The specimens were identified and females were analyzed by PCR for the DNA detection for pathogens. A total of 193 sand fly specimens belonging to five species were morphologically identified. Pintomyia ovallesi was the most abundant species (76.84%), followed by Micropygomyia cayennensis (6.40%). Furthermore, first records of four sand fly species were established for the state of Tabasco, thereby increasing the species richness in the state from four to eight. We observed a natural infection rate of 9.7% (10/103) for Leishmania and 0.91% (1/103) for Wolbachia. The importance of conducting entomological surveys in endemic areas of leishmaniasis in Mexico is highlighted, to determine whether other sand fly species may be potential vectors of Leishmania spp., and if some Wolbachia strains could be relevant for the control of leishmaniasis.

Predominance of Leishmania (Leishmania) amazonensis DNA in Lutzomyia longipalpis sand flies (Diptera: Psychodidae) from an endemic area for leishmaniasis in Northeastern Brazil.

ABSTRACTLeishmaniasis is a serious public health concern in the Northeastern region of Brazil, where the sand fly fauna is well studied, although few species have been identified as competent vectors. The detection of Leishmania spp. parasites in wild-caught sand flies could help sanitary authorities draw strategies to avoid the transmission of the parasites and, therefore, the incidence of leishmaniases. We detected Leishmania DNA in wild-caught sand flies and correlated that data with aspects of sand fly ecology in the Caxias municipality, Maranhao State, Brazil. The sand flies were sampled in the peridomicile (open areas in the vicinity of human residences) and intradomicile (inside the residences) from July/2019 to March/2020. Leishmania DNA was detected in females, targeting a fragment of the Internal Transcribed Spacer (ITS1) from ribosomal DNA. Among the fourteen species of sand flies identified, five (Lutzomyia longipalpis, Nyssomyia whitmani, Evandromyia evandroi, Micropygomyia trinidadensis, and Micropygomyia quinquefer) harbored DNA of Leishmania (Leishmania) amazonensis. The most abundant species in rural (Ny. whitmani: 35.2% and Ev. evandroi: 32.4%) and urban areas (Lu. longipalpis: 89.8%) are the permissive vectors of L. (L.) amazonensis, especially Ny. whitmani, a known vector of causative agents of cutaneous leishmaniasis. Although Lu. longipalpis is the vector of L. (L.) infantum, which was not detected in this study, its permissiveness for the transmission of L. (L.) amazonensis has been reported. We suspect that visceral leishmaniasis and cutaneous leishmaniasis are caused by L. (L.) amazonensis, and the transmission may be occurring through Lu. longipalpis, at least in the urban area.

First report of Leishmania RNA virus 1 in Leishmania (Viannia) braziliensis clinical isolates from Rio de Janeiro State - Brazil.

BACKGROUND Leishmania parasites carry a double-stranded RNA virus (Leishmania RNA virus - LRV) that has been divided in LRV1 and LRV2.OBJECTIVES Leishmania (Viannia) braziliensis clinical isolates were assessed in order to determine LRV presence.METHODS Two-round polymerase chain reaction (PCR and nested PCR) was performed to detect LRV1 or LRV2 in L. (V.) braziliensis clinical isolates (n = 12).FINDINGS LRV1 was detected in three clinical isolates which was phylogenetically related to other sequences reported from other American tegumentary leishmaniasis (ATL) endemic areas of Brazil. Patients infected with L. (V.) braziliensis LRV-negative showed only cutaneous lesions while LRV-positive reported different manifestations.MAIN CONCLUSION Data presented here show for the first time that LRV1 is circulating in L. (V.) braziliensis clinical isolates from Rio de Janeiro State in Brazil.

Entomological survey of phlebotominae sand flies (diptera: psychodidae) and vector species in the tegumentary leishmaniasis endemic area in eastern brazilian Amazon, Amapá state

Abstract: American tegumentary leishmaniasis is an endemic that has increased considerably in recent decades in the Amazon region, sand flies are the vectors of the transmission of the protozoan that causes leishmaniasis, so the objective of this study was to carry out a survey of the diversity of species and the presence of Leishmania DNA in vectors circulating in three endemic counties for tegumentary leishmaniasis in the eastern Brazilian Amazon (Amapá state, Brazil). Using CDC light traps, a total of 10,773 specimens were collected between February 2019 and February 2020, representing 64 species in 15 genera. The vector specie Nyssomyia umbratilis Ward and Frahia, 1977 was the predominant species (13.20% of the total), being collected in all three counties, followed by Trichopygomyia trichopyga Floch &amp; Abonnenc, 1945 (11.41%), Trichophoromyia ubiquitalis Mangabeira,1942 (9.47%) and Nyssomyia anduzei Rozeboom, 1942 (7.61%). For the identification of Leishmania DNA, 775 pools of unengorged females were used, of which 5 tested positive, 2 of Nyssomya umbratilis Ward &amp; Fraiha,1977, 1 of Nyssomyia anduzei and 2 of Psychodopygus davisi Root,1934, demonstrating a natural total infection rate of 0.64%. This study increases the knowledge of vector diversity, as well as identifying Leishmania spp. in circulation in the eastern region of the Amazon.

Effects of Leishmania Species on Immune Response against Malaria Parasite in Malaria Leishmania Coinfections

Both malaria and leishmania are most widespread protozoon parasitic diseases, certainly in tropical countries of the world. Malaria leishmania coinfection is common in leishmaniasis endemic areas which is mostly endemic to malaria too.&#x0D; Researchers notice that in cases of malaria leishmania coinfection , leishmania species find the some extent the outcome of malaria infection , but also behavior of malaria parasite species play a significant role to figure the consequences of it. While L. donovani protect from severe malaria complications by suppression of major histocompatibility class Ⅱ , so it diminish the clinical severity of malaria but not malaria parasite density due to dysfunction of major histocompatibility class I, which controlled by suppressed one, In another side L. mexicana tends to sequester in macrophages and lead to severe clinical outcomes when it coexisted with malaria parasite at same host. Experimental studies required to know more information about coinfection of different malaria and leishmania species to establish clinical research.&#x0D; Leishmania infection excluded when studies aim to assess the immune response to only malaria parasite, experimental studies required involving different species of malaria and leishmania.

Application of BASNEF model in students training regarding cutaneous leishmaniasis prevention behaviors: a school-based quasi experimental study

BackgroundCutaneous leishmaniasis (CL) is endemic in 98 countries, and 350 million people are at risk of the disease worldwide. In endemic areas, conducting educational interventions is necessary to change preventive behaviors of CL. This study aimed to investigate the effect of an educational intervention based on the BASNEF model on CL preventive behavior in students.MethodsThe present quasi-experimental study examined 80 students living in endemic areas of leishmaniasis in Isfahan province, Iran based on the BASNEF model. The required data were collected twice before and two months after the educational intervention based on a questionnaire whose validity and reliability had been already proven in other studies. The intervention was performed in three educational sessions for the students in the intervention group and 1 educational session for teachers and parents. Data were analyzed by SPSS (VER26) using the chi-square test, independent t-test, analysis of covariance (ANCOVA), and Paired t-test.ResultsAfter intervention, the mean scores of Knowledge (P < 0.001), attitude (P = 0.02), subjective norms (P = 0.04), behavioral intention (P < 0.001), and behavior (P = 0.02) indicated significant differences between the intervention and control groups, but an increase in mean scores of enabling factors was not significant (P = 0. 93).ConclusionsProviding students with the educational intervention based on the BASNEF model improve their ability to the extent that they transmit these educations to their family members, which would be effective in preventing and controlling CL in leishmaniasis-prone areas.Trial registrationName: Iranian Registry of Clinical Trials. Registration number: IRCT20201024049131N1. Registration date: 2020–11-20. Registration timing: prospective.

Development of an Amplicon-Based Next-Generation Sequencing Protocol to Identify Leishmania Species and Other Trypanosomatids in Leishmaniasis Endemic Areas.

ABSTRACTTrypanosomatid infections are an important public health threat affecting many low-income countries across the tropics, particularly in the Americas. Trypanosomatids can infect many vertebrate, invertebrate, and plant species and play an important role as human pathogens. Among these clinically relevant pathogens are species from the genera Leishmania and Trypanosoma. Mixed trypanosomatid infections remain a largely unexplored phenomenon. Herein, we describe the application of an amplicon-based next-generation sequencing (NGS) assay to detect and identify trypanosomatid species in mammalian reservoirs, human patients, and sand fly vectors throughout regions of Leishmania endemicity. Sixty-five samples from different departments of Colombia, including two samples from Venezuela, were analyzed: 49 samples from cutaneous leishmaniasis (CL) patients, 8 from sand flies, 2 from domestic reservoirs (Canis familiaris), and 6 from wild reservoirs (Phyllostomus hastatus). DNA from each sample served to identify the presence of trypanosomatids through conventional PCR using heat shock protein 70 (HSP70) gene as the target. PCR products underwent sequencing by Sanger sequencing and NGS, and trypanosomatid species were identified by using BLASTn against a reference database built from trypanosomatid-derived HSP70 sequences. The alpha and beta diversity indexes of amplicon sequence variants were calculated for each group. The results revealed the presence of mixed infections with more than two Leishmania species in 34% of CL samples analyzed. Trypanosoma cruzi was identified in samples from wild reservoirs, as well as in sand fly vectors. Coinfection events with three different Leishmania species were identified in domestic reservoirs. These findings depose the traditional paradigm of leishmaniasis as being a single-species-driven infection and redraw the choreography of host-pathogen interaction in the context of multiparasitism. Further research is needed to decipher how coinfections may influence disease progression. This knowledge is key to developing an integrated approach for diagnosis and treatment.IMPORTANCE Traditionally, there has been a frequent, yet incorrect assumption that phlebotomine vectors, animal reservoirs, and human hosts are susceptible to Leishmania infection by a single parasite species. However, current evidence supports that these new vector-parasite-reservoir associations lend vectors and reservoirs greater permissiveness to certain Leishmania species, thus promoting the appearance of coinfection events, particularly in disease-endemic regions. The present study describes the application of an amplicon-based next-generation sequencing (NGS) assay to detect and identify trypanosomatid species in mammalian reservoirs, human patients, and sand fly vectors from regions of endemicity for leishmaniasis. This changes our understanding of the clinical course of leishmaniasis in areas of endemicity.

Role of Leishmanin Skin Test (LST) as Epidemiological Indicator for Cutaneous Leishmaniasis in Al-tragma Village, River Nile State, Sudan

Introduction: Cutaneous leishmaniasis (CL) is a common health problem in the world and its zoonotic form has been reported to occur in Sudan. Leishmaniasis has been considered the second most important parasitic disease after malaria. Therefore, the role of leishmanin skin test (LST) as an epidemiological indicator for CL infection was determined in Al-tragma village, one of the endemic areas for the disease in Sudan. Materials and Methods: In this cross-sectional study, 410 individuals inhabiting Al-tragma village were enrolled. Two methods of data collection were used in this study, a structured questionnaire and LST. A structured questionnaire was designed to collect and test socio-demographic characteristics. The LST was performed by intradermal injection of 0.1 mL of LST antigen on the volar surface of the left forearm. The result of LST was read after 48-72 hours using the ballpoint pen technique. SPSS version 20.0 was used for data analysis. Results: LST results showed that 70.7% of respondents were positive and 29.3% were negative. The most infected age groups were 31–40 years (80%) and more than 40 years (82%). The results showed there was a significant difference in LTS results based on age groups, occupations, domestic animals and pets found in and around the houses, and previous experience of the disease (P &lt; 0.05). Conclusion: The overall positive rate for LST was 70.7%. The exposure duration had no effect on LST results. It seems that the patients acquired long-lasting immunity. LST is still a promising tool for evaluating the epidemiological status of Leishmaniasis in endemic areas.

An investigation of a new cutaneous leishmaniasis endemic area in Western Sri Lanka.

The aim was to investigate an emerging focus of cutaneous leishmaniasis (CL) in Gampaha district, Western Sri Lanka. Sociodemographics of CL patients in Mirigama, Gampaha district, were compared with controls using a structured questionnaire. Clinical data and geographic positioning system coordinates of patients were recorded. Sandflies collections were performed in four selected sites using indoor hand collection (162 units) and cattle-baited net traps (n=3). Of 73 patients (mean age 43.6 y; SD 20), 58.9% were males. Lesions consisted of nodules (52.1%) and ulcers (47.9%). Single lesions were seen in 69.9% of patients, while 30.1% had multiple lesions. Except for one mucosal lesion, all the others were cutaneous. Treatment consisted of sodium stibogluconate and cryotherapy (46.6%), sodium stibogluconate (45.2%) or cryotherapy (8.2%). Multiple lesions were more likely to receive combination therapy (p=0.013). The majority of those employed (81.1%; 27/33) were engaged in outdoor work. Male gender, low education attainment and poor disease awareness were significant risk factors for CL (p<0.05). Four households reported multiple cases. Phlebotomus argentipes was detected in all cattle-baited net traps and 35.3% of indoor hand collection units. CL is emerging in Gamapha district with Mirigama as the epicentre. Case distribution indicates local transmission, with P. argentipes as the probable vector.

Cutaneous leishmaniasis in Germany-still atravel-related disease

Cutaneous leishmaniasis is an infectious disease caused by several Leishmania species. It is transmitted to humans by the bite of the infected female phlebotomus sandfly. Today, more than 1billion people in leishmaniasis endemic areas are at risk of infection. More than 1.5million new cases of cutaneous leishmaniasis occur every year. On the basis of two cases, we show that cutaneous leishmaniasis is still an imported tropical disease in Germany. However, due to the increasing intercontinental travel, cases may increase. Therefore, cutaneous leishmaniasis should be considered in the differential diagnosis in patients with nonhealing wounds, ulcers, papules or nodules and the corresponding travel history.

PpSP32-like protein as a marker of human exposure to Phlebotomus argentipes in Leishmania donovani foci in Bangladesh

Phlebotomus argentipes is a predominant vector of Leishmania donovani, the protozoan parasite causing visceral leishmaniasis in the Indian subcontinent. In hosts bitten by P. argentipes, sand fly saliva elicits the production of specific anti-salivary protein antibodies. Here, we have utilised these antibodies as markers of human exposure to P. argentipes in a visceral leishmaniasis endemic area in Pabna district, Bangladesh. The use of whole salivary gland homogenate as an antigen to detect these antibodies has several limitations, therefore it is being superseded by the use of specific recombinant salivary proteins. We have identified three major P. argentipes salivary antigenic proteins recognised by sera of bitten humans, expressed them in a recombinant form (rPagSP04, rPagSP05 and rPagSP06) and tested their applicability in ELISA and immunoblot. One of them, PpSP32-like protein rPagSP06, was identified as the most promising antigen, showing highest resemblance and correlation with the IgG response to P. argentipes salivary gland homogenate. Furthermore, we have validated the applicability of rPagSP06 in a large cohort of 585 individuals and obtained a high correlation coefficient for anti-rPagSP06 and anti-P. argentipes saliva IgG responses. The anti-rPagSP06 and anti-P. argentipes salivary gland homogenate IgG responses followed a similar right-skewed distribution. This is the first report of screening human sera for anti-P. argentipes saliva antibodies using recombinant salivary protein. The rPagSP06 was proven to be a valid antigen for screening human sera for exposure to P. argentipes bites in a visceral leishmaniasis endemic area.

Label-Free Quantitative Proteomic Analysis of Three Strains of Viscerotropic Leishmania Isolated from Patients with Different Epidemiological Types of Visceral Leishmaniasis in China.

There are three epidemiological types of visceral leishmaniasis in China, which are caused by Leishmania strains belonging to the L. donovani complex. The mechanisms underlying their differences in the population affected, disease latency, and animal host, etc., remain unclear. We investigated the protein abundance differences among Leishmania strains isolated from three types of visceral leishmaniasis endemic areas in China. Promastigotes of the three Leishmania strains were cultured to the log phase and harvested. The protein tryptic digests were analyzed with liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS), followed by label-free quantitative analysis. The MS experiment was performed on a Q Exactive mass spectrometer. Raw spectra were quantitatively analyzed with the MaxQuant software (ver 1.3.0.5) and matched with the reference database. Differentially expressed proteins were analyzed using the bioinformatics method. The MS analysis wasrepeatedthreetimes for each sample. A total of 5012 proteins were identified across the KS-2, JIASHI-5 and SC6 strains in at least 2 of the three samples replicate. Of them, 1758 were identified to be differentially expressed at least between 2 strains, including 349 with known names. These differentially expressed proteins with known names are involved in biological functions such as energy and lipid metabolic process, nucleotide acid metabolic process, amino acid metabolic process, response to stress, cell membrane/cytoskeleton, cell cycle and proliferation, biological adhesion and proteolysis, localization and transport, regulation of the biological process, and signal transduction. The differentially expressed proteins and their related biological functions may shed light on the pathogenicity of Leishmania and targets for the development of vaccines and medicines.

Leishmaniosis felina (L. infantum) en Paraguay. Diagnóstico, tratamiento y evolución

Leishmaniosis es un conjunto de enfermedades zoonóticas causadas por protozoos del género Leishmania sp. Desde tiempo atrás se vienen registrando numerosas infecciones en caninos y en los últimos años ocurrieron casos aislados en felinos. Algunos gatos que cohabitaron en áreas endémicas de leishmaniosis canina contrajeron la enfermedad. Es probable que el sistema inmunitario del felino sea capaz de controlar la contaminación del parásito, ya sea eliminándolo o bien manteniéndolo en un estado crónico subclínico. Se reporta un caso de leishmaniosis en un felino adulto joven, residente en Asunción (Paraguay), cuya sintomatología clínica era inespecífica. Los estudios de laboratorio permitieron identificar la presencia de amastigotes de Leishmania infantum. El paciente fue sometido a tratamiento con respuesta favorable y remisión total de signos clínicos. La identificación del protozooario es determinante para el diagnóstico de esta enfermedad. Si bien la leishmaniosis es menos frecuente en felinos que en caninos, debe incluirse en el diagnóstico diferencial, especialmente en áreas endémicas.

Genetic diversity of Leishmania major strains isolated from Phlebotomus papatasi and Phlebotomus alexandri in western Iran based on minicircle kDNA.

This study aimed to screen the natural infection rate of Leishmania major in Phlebotomus papatasi and Phlebotomus alexandri in two counties (Mehran and Dehloran) of Ilam province as cutaneous leishmaniasis endemic areas in the west of Iran. Furthermore, the genetic diversity of parasite species that are isolated from vectors, was investigated. Sandflies were collected by sticky traps from May 2018 to October 2018. Afterward, specimens were prepared for species identification by morphological features. DNA was extracted from female sandflies, and minicircle kDNA was used to identify Leishmania isolates through nested-PCR, followed by genetic diversity between Leishmania isolates was investigated by sequence analysis of the amplified minicircle kDNA. Natural infection of the L. major was shown in all positive specimens using nested-PCR. Analysis of data from 14isolates displayed a high level of genetic diversity in L. major. In the phylogenetic trees, all of the L. major isolates occurred in six clusters. Clusters I, II, III, and VI contained isolated strains from P. papatasi. While clusters IV and V contained isolated strains from P. alexandri. Genetic diversity of L. major isolated from vectors was investigated in western Iran for the first time. According to the results of this study, probably "various clones of L. major populations are distributed in the study area.