scholarly journals Colonization and genetic diversification processes of Leishmania infantum in the Americas

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Philipp Schwabl ◽  
Mariana C. Boité ◽  
Giovanni Bussotti ◽  
Arne Jacobs ◽  
Bjorn Andersson ◽  
...  
Keyword(s):  
Public Health ◽  
Population Structure ◽  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Human Infection ◽  
Secondary Contact ◽  
Colonial Era ◽  
Vector Borne ◽  
Type Strains ◽  
Independent Mutation

AbstractLeishmania infantum causes visceral leishmaniasis, a deadly vector-borne disease introduced to the Americas during the colonial era. This non-native trypanosomatid parasite has since established widespread transmission cycles using alternative vectors, and human infection has become a significant concern to public health, especially in Brazil. A multi-kilobase deletion was recently detected in Brazilian L. infantum genomes and is suggested to reduce susceptibility to the anti-leishmanial drug miltefosine. We show that deletion-carrying strains occur in at least 15 Brazilian states and describe diversity patterns suggesting that these derive from common ancestral mutants rather than from recurrent independent mutation events. We also show that the deleted locus and associated enzymatic activity is restored by hybridization with non-deletion type strains. Genetic exchange appears common in areas of secondary contact but also among closely related parasites. We examine demographic and ecological scenarios underlying this complex L. infantum population structure and discuss implications for disease control.

scholarly journals Odour of domestic dogs infected with Leishmania infantum is attractive to female but not male sand flies: evidence for parasite manipulation

2020 ◽  
Author(s):  
Monica E. Staniek ◽  
James G.C. Hamilton
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Feeding Activity ◽  
Blood Feeding ◽  
Human Infection ◽  
T Test ◽  
Domestic Dogs ◽  
Lutzomyia Longipalpis ◽  
Sand Flies ◽  
Paired T Test

AbstractGlobally visceral leishmaniasis (VL) causes thousands of human deaths every year. In South America, the etiologic agent, Leishmania infantum, is transmitted from an infected canine reservoir to human hosts by the blood-feeding activity of the sand fly vector, predominantly, Lutzomyia longipalpis. Previous evidence from model rodent systems have suggested that the odour of infected hosts is altered by the parasite making them more attractive to the vector leading to an increased biting rate and improved transmission prospects for the pathogen. However, the effect of Le. infantum infection on the attractiveness of naturally infected dogs which are integral to human infection, has not been assessed.Hair collected from infected and uninfected dogs residing in a VL endemic city in Brazil. was entrained to collect the volatile chemical odours present in the headspace. Female and male Lu. longipalpis sand flies were offered a choice of infected or uninfected odour in a series of behavioural experiments. Control experiments established that female and male Lu. longipalpis were equally attracted to uninfected dog odour, female Lu. longipalpis were significantly more attracted to infected dog odour than uninfected dog odour in all 15 experimental replicates (average 45.7±0.87 females attracted to infected odour; 23.9±0.82 to uninfected odour; paired T-test, P=0.000). Male Lu. longipalpis did not significantly prefer either infected or uninfected odour (average 36.1±0.4 males to infected odour; 35.7±0.6 to uninfected odour; paired T-test, P=0.722). A significantly greater proportion of females chose the infected dog odour compared to the males (paired T-test, P=0.000).The results show that dogs infected with Le. infantum are significantly more attractive to blood-feeding female than male sand flies. This is strong evidence for parasite manipulation of the host odour in a natural transmission system and indicates that infected dogs may have a disproportionate significance in maintaining infection in canine and human infection.Author SummaryVisceral leishmaniasis (VL) is a disease caused by the Protist parasite Leishmania infantum. In Brazil and other South and Central American countries, the parasite is transmitted by the blood-feeding activity of infected female Lutzomyia longipalpis sand flies. The disease leads to thousands of human cases and deaths every year. Domestic dogs are the reservoir of infection for humans therefore understanding the effect of infection on dogs is important in developing an understanding of the epidemiology of the disease. Although previous studies on rodent models of Le. infantum infection have shown that infected Golden Hamsters are more attractive to Lu. longipalpis the attractiveness of naturally infected dogs to the insect vector has not been previously been investigated. In this study we showed that the odour of infected dogs is significantly more attractive to female sand flies which can transmit the pathogen than to male sand flies which do not. This clear-cut difference in attraction of female and males suggests that the females are preferentially attracted by parasite infected hosts and may lead to enhanced infection and transmission opportunities for the parasite.

scholarly journals Resistance to Experimental Visceral Leishmaniasis in Mice Infected With Leishmania infantum Requires Batf3

2020 ◽  
Vol 11 ◽  
Author(s):  
Manuel Soto ◽  
Laura Ramírez ◽  
José Carlos Solana ◽  
Emma C. L. Cook ◽  
Elena Hernández-García ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Rational Design ◽  
Leucine Zipper ◽  
Basic Leucine Zipper ◽  
Vector Borne ◽  
The Impact ◽  
Deficient Mice

Unveiling the protective immune response to visceral leishmaniasis is critical for a rational design of vaccines aimed at reducing the impact caused by this fatal, if left untreated, vector-borne disease. In this study we sought to determine the role of the basic leucine zipper transcription factor ATF-like 3 (Batf3) in the evolution of infection with Leishmania infantum, the causative agent of human visceral leishmaniasis in the Mediterranean Basin and Latin America. For that, Batf3-deficient mice in C57BL/6 background were infected with an L. infantum strain expressing the luciferase gene. Bioluminescent imaging, as well as in vitro parasite titration, demonstrated that Batf3-deficient mice were unable to control hepatic parasitosis as opposed to wild-type C57BL/6 mice. The impaired microbicide capacities of L. infantum-infected macrophages from Batf3-deficient mice mainly correlated with a reduction of parasite-specific IFN-γ production. Our results reinforce the implication of Batf3 in the generation of type 1 immunity against infectious diseases.

An unusual case of post-kala-azar dermal leishmaniasis in a patient with HIV and visceral leishmaniasis co-infection

2019 ◽  
Vol 30 (12) ◽  
pp. 1221-1223
Author(s):  
Tamara Elliott ◽  
Jacqueline Simpson ◽  
Kikkeri N Naresh ◽  
Diana Lockwood ◽  
Angela C Bailey
Keyword(s):  
Human Immunodeficiency Virus ◽  
Visceral Leishmaniasis ◽  
Leishmania Infantum ◽  
Leishmania Donovani ◽  
Unusual Case ◽  
Vector Borne Disease ◽  
Kala Azar ◽  
Immunodeficiency Virus ◽  
Vector Borne

Visceral leishmaniasis (VL) is a vector-borne disease caused by Leishmania donovani complex. Post-kala-azar dermal leishmaniasis (PKDL) is a rash that can occur following treatment for VL due to L. donovani species. We describe an unusual case of PKDL occurring during treatment for Leishmania infantum VL in a patient with human immunodeficiency virus-co infection.

scholarly journals Leishmania infantumGenetic Diversity andLutzomyia longipalpisMitochondrial Haplotypes in Brazil

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Paulo Eduardo Martins Ribolla ◽  
Letícia Tsieme Gushi ◽  
Maria do Socorro Pires e Cruz ◽  
Carlos Henrique Nery Costa ◽  
Dorcas Lamounier Costa ◽  
...  
Keyword(s):  
Population Structure ◽  
Genetic Structure ◽  
Visceral Leishmaniasis ◽  
Disease Transmission ◽  
Leishmania Infantum ◽  
Domestic Dogs ◽  
Etiological Agent ◽  
Lutzomyia Longipalpis ◽  
Geographic Structure ◽  
Reservoir Hosts

Leishmania infantumis the etiological agent of visceral leishmaniasis (VL) in the Americas with domestic dogs being its major reservoir hosts. The main VL vector is the sandflyLutzomyia longipalpis, while otherLutzomyiaspecies may play a role in disease transmission. Although the genetic structure ofL. infantumpopulations has been widely evaluated, only a few studies have addressed this subject coupled to the genetic structure of the respective sandfly vectors. In this study, we analyzed the population structure ofL. infantumin three major VL endemic areas in Brazil and associated it withLutzomyia longipalpisgeographic structure.

scholarly journals Molecular detection of Leishmania spp. in cattle from Brazil by means of PCR using internal transcribed spacer 1

2019 ◽  
Vol 28 (2) ◽  
pp. 303-305
Author(s):  
Geovanna Vioti ◽  
João Augusto Franco Leonel ◽  
Kleber Menegon Lemes ◽  
Vanessa Figueredo Pereira ◽  
Helena Lage Ferreira ◽  
...  
Keyword(s):  
Public Health ◽  
Visceral Leishmaniasis ◽  
Internal Transcribed Spacer ◽  
Leishmania Infantum ◽  
Endemic Area ◽  
Molecular Detection ◽  
The State ◽  
Base Pairs ◽  
Blood Samples ◽  
Leishmania Spp

Abstract Leishmania spp. are important agents of human and animal leishmaniases that have an important impact on public health. In this study, we aimed to detect the circulation of Leishmania spp. in cattle from a visceral leishmaniasis non-endemic area of the state of São Paulo, Brazil. DNA was extracted from blood samples from 100 heifers in the municipality of Pirassununga and was amplified using primers specific for the first internal transcriber spacer (ITS1), to assess the presence of trypanosomatids. The assays revealed that one sample presented bands of between 300 and 350 base pairs. In GenBank, this sample matched 100% with Leishmania infantum (314 base pairs). The results suggest that cattle can be infected by Leishmania infantum in Brazil.

scholarly journals Cutaneous Leishmaniasis in Algeria; Highlight on the Focus of M’Sila

2021 ◽  
Vol 9 (5) ◽  
pp. 962
Author(s):  
Razika Beniklef ◽  
Karim Aoun ◽  
Karim Boudrissa ◽  
Meriem Ben Abid ◽  
Kamel Cherif ◽  
...  
Keyword(s):  
Risk Factors ◽  
Visceral Leishmaniasis ◽  
Cutaneous Leishmaniasis ◽  
Leishmania Infantum ◽  
Psammomys Obesus ◽  
Phlebotomus Papatasi ◽  
Wild Rodents ◽  
High Incidence ◽  
Medical Importance ◽  
Underlying Risk

Algeria ranks second after Afghanistan for the incidence of cutaneous leishmaniasis (CL) worldwide. Here, we report a 34-years retrospective analysis of CL in Algeria and focused on the most affected region, the M’Sila province. All 66 cutaneous isolates corresponded to Leishmania (L.) major. Our study of the sandfly and rodent fauna further highlighted the high density of Phlebotomus papatasi and additional phlebotomine species of medical importance, not previously identified in M’Sila. Wild rodents belonging to nine species were trapped in M’Sila, and Psammomys obesus and Meriones shawi were found infected by L. major. In addition, Leishmania infantum was isolated from two visceral leishmaniasis cases, one dog and its proven vectors (P. perniciosus, P. longicuspis, and P. perfiliewi) inventoried during the survey. The high incidence of CL in the M’Sila province is likely a consequence of the increase in minimum temperatures recorded that constitutes suitable conditions for establishing a high endemicity and leads to an explosive rise in leishmaniases cases in this region. A thorough investigation of the underlying risk factors is urgently needed to detect new cases earlier. All these would improve the preparedness to fight the disease.

scholarly journals First molecular detection of hepatitis E virus genome in camel and pig faecal samples in Ethiopia

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Fufa Dawo Bari ◽  
Haimanot Belete Wodaje ◽  
Umer Said ◽  
Hika Waktole ◽  
Melaku Sombo ◽  
...  
Keyword(s):  
Public Health ◽  
Hepatitis E Virus ◽  
Addis Ababa ◽  
Hepatitis E ◽  
Human Infection ◽  
Health Concern ◽  
Universal Primers ◽  
Viral Gene ◽  
Public Health Importance ◽  
Faecal Samples

Abstract Background Hepatitis E is an enteric and zoonotic disease caused by hepatitis E virus (HEV) that is mainly transmitted via the faecal-oral route through contaminated food or the environment. The virus is an emerging infectious agent causing acute human infection worldwide. A high seroprevalence of the disease was reported in pregnant women in Addis Ababa, Ethiopia, raising significant public health concern. The presence of HEV specific antibodies were also reported in dromedary camels in the country; however, the infectious virus and/or the viral genome have not been demonstrated to date in animal samples. Methods To address this gap, a total of 95 faecal samples collected from both apparently healthy pigs of uncharacterised types (50 samples) in Burayu and Addis Ababa areas and camels (Camelus dromedarius, 45 samples) in west Hararghe were screened for the presence of HEV genome using universal primers in a fully nested reverse transcription polymerase chain reaction (nRT-PCR). The protocol is capable of detecting HEV in faecal samples from both pigs and camels. Results The nRT-PCR detected HEV genes in six (12%) pig faecal samples and one camel sample (2.2%). Therefore, the results indicate that HEV is circulating in both pigs and camels in Ethiopia and these animals and their products could serve as a potential source of infection for humans. Conclusion The detection of HEV in both animals could raise another concern regarding its public health importance as both animals’ meat and camel milk are consumed in the country. Further studies to determine the prevalence and distribution of the virus in different animals and their products, water bodies, food chain, and vegetables are warranted, along with viral gene sequencing for detailed genetic characterisation of the isolates circulating in the country. This information is critically important to design and institute appropriate control and/or preventive measures.

scholarly journals Vector-Borne Pathogens with Veterinary and Public Health Significance in Melophagus ovinus (Sheep Ked) from the Qinghai-Tibet Plateau

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 249
Author(s):  
Qing-Xun Zhang ◽  
Ye Wang ◽  
Ying Li ◽  
Shu-Yi Han ◽  
Bo Wang ◽  
...  
Keyword(s):  
Public Health ◽  
Molecular Characterization ◽  
Tibet Plateau ◽  
Border Disease Virus ◽  
Public Health Significance ◽  
Melophagus Ovinus ◽  
Health Significance ◽  
Vector Borne ◽  
Qinghai Tibet Plateau

Melophagus ovinus (sheep ked) is a hematophagous ectoparasite that mainly parasitizes sheep. In addition to causing inflammation, wool loss, and skin damage to the animal hosts, M. ovinus also serves as a vector for a variety of pathogens and is highly likely to participate in the life and transmission cycle of pathogenic organisms. Herein, we investigated the presence and molecular characterization of vector-borne pathogens in M. ovinus from Qinghai-Tibet Plateau, China. A total of 92 M. ovinus pools collected from the Qinghai province of China were screened for the presence of selected vector-borne pathogens. The overall positive rate of A. ovis, A. bovis, A. phagocytophilum, and T. ovis in M. ovinus was 39.1%, 17.4%, 9.8%, and 89.1%, respectively. All of the samples were negative for Border disease virus (BDV), other Anaplasma species, Babesia spp., Rickettsia spp., and Borrelia spp. Co-infection of different Anaplasma species and T. ovis occurred in 51.2% of all samples with T. ovis. The positive rates of A. ovis, A. bovis, and A. phagocytophilum in different regions and altitudes of the sampling sites were significantly different. Sequence and phylogenetic analysis of target genes confirmed their identity with corresponding pathogens. Our results elucidate the occurrence and molecular characterization of Anaplasma spp. and Theileria spp. in M. ovinus, which could act as potential zoonotic reservoirs. To the best of our knowledge, this is the first report of the detection of A. bovis and A. phagocytophilum DNA in M. ovinus. This study gives the first extensive molecular survey of vector-borne pathogens with veterinary and public health significance in M. ovinus from the Qinghai-Tibet Plateau, China.

scholarly journals Clinical and laboratory profiles of visceral leishmaniasis among adult patients admitted to Felege Hiwot Hospital, Bahir Dar, Ethiopia

2021 ◽  
Vol 9 ◽  
pp. 205031212110367
Author(s):  
Berhanu Tarekegn ◽  
Ayanaw Tamene
Keyword(s):  
Visceral Leishmaniasis ◽  
Leishmania Donovani ◽  
Clinical Presentation ◽  
Winter Season ◽  
Adult Patients ◽  
Sand Fly ◽  
Timely Initiation ◽  
Vector Borne Disease ◽  
Vector Borne ◽  
Endemic Areas

Background: Visceral leishmaniasis is a vector-borne disease caused by Leishmania donovani transmitted by sand fly species. It is the third most common vector-borne disease globally. Visceral leishmaniasis is endemic in Ethiopia with an estimated annual incidence ranging from 3700 to 7400 cases. This research aimed to assess the clinical presentations and laboratory profiles of visceral leishmaniasis for early diagnosis and timely initiation of management. Objective: To describe the clinical and laboratory manifestation and diagnostic modalities of visceral leishmaniasis among adult patients admitted to Felege Hiwot Hospital, from 1 September 2016 to 30 August 2019. Method: Institution-based retrospective cross-sectional study was conducted among 141 patients admitted to Felege Hiwot Hospital from 1 September 2016 to 30 August 2019. Descriptive statistics were used to describe the clinical presentation and laboratory profiles of patients with visceral leishmaniasis. Results: Among a total of 141 enrolled patients in the study, males were affected 13-fold. Most of them were travelers to endemic areas during the winter season for labor work. The mean duration of illness was 48 days. Common symptoms were fever (96.5%), weightless (82.5%), jaundice (18.4%), vomiting/diarrhea (13.5%), and bleeding episodes (11.3%). Splenomegaly was seen in 98.6%, ascites in 35.5%, and lymphadenopathy in 9.9%. Lymphadenopathy was seen significantly in HIV patients (40%). Anemia was seen in 95%, thrombocytopenia in 90.2%, leukopenia in 86.4%, and pancytopenia in 79.4%. Half of the patients had coinfection. Neutropenic sepsis was seen in 21.3%. The diagnosis was made by tissue aspiration in 65% of patients. Conclusion: The majority of patients who were diagnosed to have visceral leishmaniasis were young male adults who traveled to the endemic areas seasonally. Fever and splenomegaly were seen as the commonest clinical presentation. Lymphadenopathy occurred in high frequency among HIV co-infected patients. Anemia was the commonest hematologic finding.

scholarly journals Experimental Evaluation of Second-Line Oral Treatments of Visceral Leishmaniasis Caused by Leishmania infantum

1999 ◽  
Vol 43 (1) ◽  
pp. 172-174 ◽  
Author(s):  
Jean-Pierre Gangneux ◽  
Michael Dullin ◽  
Annie Sulahian ◽  
Yves Jean-Francois Garin ◽  
Francis Derouin
Keyword(s):  
Visceral Leishmaniasis ◽  
Murine Model ◽  
Experimental Evaluation ◽  
Leishmania Infantum ◽  
Parasite Load ◽  
Second Line ◽  
Meglumine Antimoniate ◽  
Marked Activity

ABSTRACT In a murine model of Leishmania infantum visceral leishmaniasis, metronidazole, ketoconazole, fluconazole, itraconazole, and terbinafine were less effective than antimonial agents in reducing hepatic parasite load. Ketoconazole potentiated the effect of meglumine antimoniate reference therapy through its marked activity against spleen infection.

Sign in / Sign up

Export Citation Format

Share Document