Relationships between specific antibody responses and clinical signs of dogs living in Tunisian endemic areas of canine leishmaniasis caused by Leishmania infantum

Zoonotic leishmaniasis caused by Leishmania infantum is a disease of One Health concern since human and animal cases and environmental damage are interconnected. L. infantum has a complex epidemiological cycle with multiple hosts, including mammals—humans, domestic, and wild animals—and arthropod vectors. Knowledge on mammal infections in endemic areas is crucial for developing control strategies. This work aimed to detect and characterize L. infantum infection in domestic cats from areas where human and canine leishmaniasis cases occur. No cases of feline leishmaniasis (FeL) had been previously reported in those areas. Five municipalities from Bahia state were chosen, comprising 2,480.8 km2 with 1,103,866 inhabitants. Ninety domiciliated and/or sheltered cats underwent clinical examination and serology by a rapid reference test recommended by the Brazilian government. Cytology, PCR, and parasite DNA sequencing were performed in bone marrow samples. Rapid tests detected antibodies in 5.6% (5/90) of the cats. Leishmania infantum infection was confirmed in 7.8% (7/90) of the cats by PCR, sequencing, and parasite isolation. Three out of the five municipalities (60%) had infected cats, and PCR positivity varied from 6.9 to 29%. One cat was categorized as harboring active L. infantum infection with amastigote forms in bone marrow smears. No clinical signs were detected at the first clinical exam, but 1 month later the cat developed severe FeL. The cat isolate was grown in culture, typed and its DNA sequence was homologous to the L. infantum reference strain (PP75). In conclusion, cats are potential hosts and may acquire L. infantum in endemic areas where canine and human cases occur. For cats, the need for surveillance, differential diagnosis and clinical care is highly recommended since a fast clinical progression of FeL developed in a subclinical animal. An accurate standardized immunodiagnostic assay for FeL is warranted.

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CD45+, CD68+ and E-cadherin+ Expressions in Skin Dogs Naturally Infected by Leishmania infantum

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.79402 ◽

2017 ◽

Vol 45 (1) ◽

pp. 7

Author(s):

Társsila Mara Vieira Ferreira ◽

Tiago Cunha Ferreira ◽

Fernanda Maria Aragão Ximenes Porto ◽

Conceição Da Silva Martins ◽

Berlamino Eugênio Lopes Neto ◽

...

Keyword(s):

Leishmania Infantum ◽

Mononuclear Cells ◽

Plasma Cells ◽

Clinical Signs ◽

Clinical Manifestations ◽

Canine Leishmaniasis ◽

Control Group ◽

Asymptomatic Group ◽

G Ratio ◽

E Cadherin

Background: In canine leishmaniasis (CanL), infection occurs through phlebotomine vectors that inoculate the protozoan Leishmania infantum into the skin that infected macrophages and activated dendritic cells (CD). Dogs with CanL present variable clinical manifestations, being common the presence of cutaneous lesions. The aim of this study was to evaluate the expression of CD45+, CD68+ and E-cadherin+ associating the skin sentinels cells and to compare the clinical-dermatological manifestations in the skin of dogs naturally infected by L. infantum.Materials, Methods & Results: Dogs infected (n = 22) by L. infantum were divided into asymptomatic group (AD, n = 9), and symptomatic group (SD, n = 13), according criteria based on the presence or absence of skin changes. Dogs non-infected (CD, n = 5) were included as control group. Samples of skin biopsies collected from scapular region were processed by routine histology and labeled by immunohistochemistry with monoclonal antibodies against CD45+, CD68+ and E-cadherin+, and were described as none, mild, moderate and intense. SD presented keratoconjunctivitis, onychogryphose, lichenification, depigmentation, alopecia, hypotrichosis, erythematous dermatitis, exfoliative dermatitis, ulcerative dermatitis and crusted dermatitis, and the frequency these alterations was expressed as percentage. The results of hematological and biochemical parameters were analyzed by Kruskal-Wallis test followed by the Dunn’s test and expressed as mean ± standard deviation, with values P < 0.05. Leukocytosis (not significant), red blood cells, hematocrit and hemoglobin (P < 0.05), total protein serum (P < 0.05), globulins (P < 0.05), albumin and A/G ratio (P < 0.01) were altered in SD in relation to CD. Cutaneous cellular infiltration, composed by macrophages, plasma cells, lymphocytes and neutrophils, was observed in CD. There was an increase of expression of the markers in SD when compared to the other groups, as moderate CD68+ expression and L. infantum, and intense CD45+ and E-cadherin+ expressions.Discussion: Cutaneous involvement is very important in CanL, as it corresponds to where is the first interaction between the parasite and the immune system. Dermatological clinical signs, leukocytosis, anemia, globulins levels have been reported for dogs naturally infected by L. infantum. Inflammatory infiltrate was distributed at superficial and deep dermis, which was composed by mononuclear cells as macrophages, plasma cells, lymphocytes and neutrophils. To characterize the immune sentinels cells in the skin it was evaluated CD45+, CD68+ and E-cadherin+ expressions. In syntomatic dogs, our results revelead an increase of expression of these markers. CD45+ is one of the most abundant molecules expressed on the white blood cell surface in various mammals, while CD68+ is a myelomonocytic marker that seems to be retained during monocyte differentiation. In the skin, increased numbers of CD68+ are related to dendritic epidermal cells, which can be expressed as CD45+/CD1a-/HLA-DR+. DCs of the skin, particularly epidermal Langerhans cells (LCs), form networks anchored to neighboring keratinocytes via E-cadherin. Thus, CD45+, CD68+ and E-cadherin+ expressions may be related to activation of skin sentinels cells in dogs naturally infected by L. infantum. Our results indicated that CanL modify the CD45+, CD68+ and E-cadherin+ expressions, which characterize the immune sentinels cells activation that promove the recruitment the cellular infiltrate, which was composed by macrophages, plasma cells, lymphocytes and neutrophils. Thus, these informations may contribute to the follow-up of CanL progression in skin.

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Toward Diagnosing Leishmania infantum Infection in Asymptomatic Dogs in an Area Where Leishmaniasis Is Endemic

Clinical and Vaccine Immunology ◽

10.1128/cvi.00268-08 ◽

2009 ◽

Vol 16 (3) ◽

pp. 337-343 ◽

Cited By ~ 45

Author(s):

D. Otranto ◽

P. Paradies ◽

D. de Caprariis ◽

D. Stanneck ◽

G. Testini ◽

...

Keyword(s):

Leishmania Infantum ◽

Clinical Signs ◽

Antibody Test ◽

Diagnostic Methods ◽

Canine Leishmaniasis ◽

Enzyme Linked Immunosorbent Assay ◽

Canine Monocytic Ehrlichiosis ◽

Immunofluorescence Antibody Test ◽

Immunofluorescence Antibody

ABSTRACT The most frequently used diagnostic methods were compared in a longitudinal survey with Leishmania infantum-infected asymptomatic dogs from an area of Italy where leishmaniasis is endemic. In February and March 2005, 845 asymptomatic dogs were tested by an immunofluorescence antibody test (IFAT), a dipstick assay (DS), and an enzyme-linked immunosorbent assay (ELISA) for L. infantum and by IFAT for Ehrlichia canis. Dogs seronegative for L. infantum were further parasitologically evaluated by microscopic examination of lymph node tissues and PCR of skin samples. A total of 204 animals both serologically and parasitologically negative for L. infantum at the first sampling were enrolled in the trial and were further examined for canine leishmaniasis (CanL) and canine monocytic ehrlichiosis in November 2005 (i.e., the end of the first sandfly season) and March 2006 and 2007 (1- and 2-year follow-ups, respectively). At the initial screening, the overall rates of L. infantum seroprevalence were 9.5% by IFAT, 17.1% by ELISA, and 9.8% by DS and the overall rate of E. canis seroprevalence was 15%. The rates of concordance between the results of IFAT and DS were almost equal, whereas the rate of concordance between the results of IFAT and DS and those of the ELISA was lower. The results of the annual incidence of Leishmania infection were variable, depending on the test employed, with the highest values registered for PCR (i.e., 5.7% and 11.4% at the 1- and 2-year follow-ups, respectively), followed by ELISA, IFAT, and DS. Over the 2 years of observation, 55 animals (i.e., 26.9%) became positive for L. infantum by one or more diagnostic tests at different follow-up times, with 12.7% showing clinical signs related to CanL, while the remaining 87.3% were asymptomatic. A diagnostic scheme for assessment of the L. infantum infection status in asymptomatic dogs is suggested.

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Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum

10.21203/rs.2.22702/v3 ◽

2020 ◽

Author(s):

Maria Alfonsa Cavalera ◽

Roberta Iatta ◽

Pietro Laricchiuta ◽

Giuseppe Passantino ◽

Francesca Abramo ◽

...

Keyword(s):

Leishmania Infantum ◽

Cutaneous Lesion ◽

Clinical Signs ◽

Average Concentration ◽

Screening Tests ◽

Panthera Tigris ◽

Clinicopathological Findings ◽

Group A ◽

Endemic Areas ◽

Group B

Abstract Background A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum. Results Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p<0.01, p=0.01 and p=0.02, respectively), while the albumin/globulin ratio significantly lower (p=0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p=0.01) and hypergammaglobulinemia (p=0.03) but an unmodified albumin/globulin ratio in group A.Conclusions In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.

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Leishmania infantum-specific IgG, IgG1 and IgG2 antibody responses in healthy and ill dogs from endemic areas

Veterinary Parasitology ◽

10.1016/s0304-4017(00)00446-5 ◽

2001 ◽

Vol 96 (4) ◽

pp. 265-276 ◽

Cited By ~ 94

Author(s):

Laia Solano-Gallego ◽

Cristina Riera ◽

Xavier Roura ◽

Laura Iniesta ◽

Montserrat Gallego ◽

...

Keyword(s):

Leishmania Infantum ◽

Antibody Responses ◽

Igg2 Antibody ◽

Specific Igg ◽

Endemic Areas

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Effectiveness of a Simultaneous rHVT-F(ND) and rHVT-H5(AI) Vaccination of Day-Old Chickens and the Influence of NDV- and AIV-Specific MDA on Immune Response and Conferred Protection

Vaccines ◽

10.3390/vaccines8030536 ◽

2020 ◽

Vol 8 (3) ◽

pp. 536

Author(s):

Fabienne Rauw ◽

Eva Ngabirano ◽

Yannick Gardin ◽

Vilmos Palya ◽

Bénédicte Lambrecht

Keyword(s):

Avian Influenza ◽

Specific Antibody ◽

Newcastle Disease ◽

Clinical Signs ◽

Antibody Responses ◽

Single Shot ◽

Negative Effects ◽

Vector Vaccine ◽

Viral Shedding ◽

Pathogenic Avian Influenza Virus

The recombinant herpesvirus of turkey (rHVT) vaccines targeting Newcastle disease (ND) and H5Nx avian influenza (AI) have been demonstrated efficient in chickens when used individually at day-old. Given the practical field constraints associated with administering two vaccines separately and in the absence of a currently available bivalent rHVT vector vaccine expressing both F(ND) and H5(AI) antigens, the aim of this study was to investigate whether interference occurs between the two vaccines when simultaneously administered in a single shot. The studies have been designed to determine (i) the ND and AI-specific protection and antibody response conferred by these vaccines inoculated alone or in combination at day-old, (ii) the influence of maternally-derived antibodies (MDA), and (iii) the potential interference between the two vaccine. Our results demonstrate that their combined administration is efficient to protect chickens against clinical signs of velogenic Newcastle disease virus (vNDV) and H5-highly pathogenic avian influenza virus (HPAIV) infections. Viral shedding following co-vaccination is also markedly reduced, while slightly lower NDV- and AIV-specific antibody responses are observed. NDV- and AIV-specific MDA show negative effects on the onset of the specific antibody responses. However, if AIV-specific MDA reduce the protection against H5-HPAIV induced by rHVT-H5(AI) vaccine, it was not observed for ND.

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A comparative study of nested-PCR and direct agglutination test (DAT) for the detection of Leishmania infantum infection in symptomatic and asymptomatic domestic dogs

BMC Research Notes ◽

10.1186/s13104-021-05654-0 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Yonas Yimam Ayene ◽

Mehdi Mohebali ◽

Homa Hajjaran ◽

Behnaz Akhoundi ◽

Saeedeh Shojaee ◽

...

Keyword(s):

Nested Pcr ◽

Leishmania Infantum ◽

Venous Blood ◽

Clinical Signs ◽

Agglutination Test ◽

Domestic Dogs ◽

Direct Agglutination Test ◽

Nested Polymerase Chain Reaction ◽

Endemic Areas ◽

Visceral Leishmaniosis

Abstract Objective Canine visceral leishmaniasis (CVL) is the main source of human visceral leishmaniosis (HVL) in Mediterranean region, including Iran and is spread from domestic dogs to Phlebotomine sand flies vectors to humans. To control the transmission of HVL, early and accurate detection of infected dogs is paramount importance despite it remains a confronting challenge. Herein, we evaluated the performance of direct agglutination test (DAT) against gold standard nested polymerase chain reaction (nested-PCR) for CVL diagnosis in symptomatic and asymptomatic domestic dogs from endemic areas of Iran. Results Venous blood samples were collected from dogs without clinical signs (n = 30) and with clinical signs (n = 35) suggestive of Leishmania infantum infection. Among 65 samples examined, Leishmania DNA was detected by nested-PCR in 89.23% (58/65). Furthermore, 86.15% (56/65) nested-PCR positive samples were also DAT positive. The results of the DAT sensitivity test were 96.43% and 96.67% in symptomatic and asymptomatic dogs, respectively, while the specificity was 100.00% and 60.00% in symptomatic and asymptomatic dogs, respectively. The results of this study also pointed out substantial concordance between DAT test and nested-PCR method in both symptomatic dogs (Κ = 0.783; P < 0.001) and asymptomatic dogs (Κ = 0.618; P < 0.001). Thus, DAT represents as a simple and economic tool for initial diagnosis of CVL particularly in endemic areas of the disease.

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Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum

10.21203/rs.2.22702/v1 ◽

2020 ◽

Author(s):

Maria Alfonsa Cavalera ◽

Roberta Iatta ◽

Pietro Laricchiuta ◽

Giuseppe Passantino ◽

Francesca Abramo ◽

...

Keyword(s):

Leishmania Infantum ◽

Cutaneous Lesion ◽

Clinical Signs ◽

Average Concentration ◽

Screening Tests ◽

Panthera Tigris ◽

Clinicopathological Findings ◽

Group A ◽

Endemic Areas ◽

Group B

Abstract Background A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum. Results Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p<0.01, p=0.01 and p=0.02, respectively), while the albumin/globulin ratio significantly lower (p=0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p=0.01) and hypergammaglobulinemia (p=0.03) but an unmodified albumin/globulin ratio in group A.Conclusions In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.

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Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum

10.21203/rs.2.22702/v2 ◽

2020 ◽

Author(s):

Maria Alfonsa Cavalera ◽

Roberta Iatta ◽

Pietro Laricchiuta ◽

Giuseppe Passantino ◽

Francesca Abramo ◽

...

Keyword(s):

Leishmania Infantum ◽

Cutaneous Lesion ◽

Clinical Signs ◽

Average Concentration ◽

Screening Tests ◽

Panthera Tigris ◽

Clinicopathological Findings ◽

Group A ◽

Endemic Areas ◽

Group B

Abstract Background A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum. Results Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p<0.01, p=0.01 and p=0.02, respectively), while the albumin/globulin ratio significantly lower (p=0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p=0.01) and hypergammaglobulinemia (p=0.03) but an unmodified albumin/globulin ratio in group A. Conclusions In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.

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Canine Leishmaniasis in Morocco: A Descriptive Prospective Clinical Study

Veterinary Medicine International ◽

10.1155/2021/6304127 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Houda Idrissi ◽

Maryam Hakkour ◽

Luc Duchateau ◽

Renato Zanatta ◽

Malika Kachani ◽

...

Keyword(s):

Urban Areas ◽

Leishmania Infantum ◽

Clinical Signs ◽

Clinical Manifestations ◽

Outdoor Environment ◽

Exercise Intolerance ◽

Canine Leishmaniasis ◽

Effective Control ◽

Prospective Clinical Study ◽

Free Access

Canine leishmaniasis (CanL) is a zoonotic vector-borne disease that is endemic in the Mediterranean Basin including Morocco. Dogs play a major epidemiological role in this zoonosis as reservoir hosts. This study investigated the clinical manifestations of CanL in dogs naturally infected with Leishmania infantum. A total of 96 dogs presented to the Small Animal Clinic of the Hassan II Agronomy and Veterinary Institute (IAV Hassan II) of Rabat, Morocco, and were tested by RT-PCR and/or serology. Among them, 32 (33.3%) were positive to Leishmania infantum infection. The majority of the positive dogs (93.7%) came from urban areas. Most of them were male (62.5%) and purebreds (65.6%), were aged between 3 and 7 years (71.8%), and had outside activities (guarding, hunting, livestock guarding, and service activities) (71.8%) and all of them were living exclusively outdoor or had free access to the outdoor environment. Lymphadenomegaly (81.2%), dermatological disorders (65.6%) (mostly exfoliative dermatitis), weight loss (59.3%), exercise intolerance (56.2%), anorexia (28.1%), hyporexia (15.6%), and ocular lesions (28.1%) were the most frequent clinical signs and complaints recorded. Anemia and hyperproteinemia due to hyperglobulinemia were observed in 68.7% and 72.7% of the cases, respectively. These results suggest that CanL leads to various nonspecific clinical signs as described previously, making the diagnosis challenging. Since CanL is endemic in Morocco, it should be recommended to systematically test dogs displaying clinical signs compatible with this disease and to regularly screen asymptomatic at-risk dogs. It is also crucial to educate dog owners about the zoonotic aspect of the disease and to encourage intersectorial collaboration following the “One Health” concept, in order to contribute to a more effective control/prevention of human and canine leishmaniasis.

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