Molecular e serological detection of Leishmania infantum (Trypanosomatida: Trypanosomatidae) in domestic dogs in Manaus city, Amazonas, Brazil.

Leishmaniasis are zoonosis widely spread in Brazil, caused by the protozoan of the genus Leishmania, which includes several species. The disease manifests itself in the visceral or tegumentary form, and the main reservoir is the dogs. Manaus is the largest city in the Brazilian Amazon region, and despite the importance of the municipality, practically nothing is known about leishmaniosis in humans and animals. The objective of this study was to evaluate the occurrence and risk factors associated with the presence of Leishmania infantum in domiciliated dogs from Manaus. Molecular (polymerase chain reaction) and serological (immunofluorescent antibody test) methods were used as an indication of the circulation of the parasite. Blood samples for 154 domiciled dogs were obtained, and prevalence ratio and analysis of the variables were performed. Serum antibodies anti-Leishmania spp. were detected in 20.8% (95% CI: 14.4%-27.2%). Access to the street and zone of residence (P < 0.01) were associated with higher seropositivity. Molecular diagnosis for L. infantum detected positivity in 60 (39%) of the 154 (95% CI: 31.3%-46.7%) animals, and the variables street access, contact with dogs, and zone of residence were associated with higher frequencies of positivity (P < 0.05). Both serology and molecular diagnosis detected positive dogs in the municipality. This is the first description of the circulation of L. infantum infecting dogs in Manaus. As the municipality is classified as nonendemic, studies of isolation and characterization of the isolate must be done urgently.

Molecular Investigation Confirms Myotis Genus Bats as Common Hosts of Polychromophilus in Brazil.

Plasmodium spp. and some other blood parasites belonging to the order Haemosporida are the focus of many epidemiological studies worldwide. However, haemosporidian parasites from wild animals are largely neglected in scientific research. For example, Polychromophilus parasites, which are exclusive to bats, are described in Europe, Asia, Africa, and Oceania, but little is known about their presence and genetic diversity in the New World. In this study, 224 samples of bats from remaining fragments of the Atlantic Forest and Pantanal biomes, as well as urbanized areas in southern and southeastern Brazil, were analyzed for the presence of haemosporidian parasites by PCR of the mitochondrial gene that encodes cytochrome b (cytb). The PCR fragments of the positive samples were sequenced and analyzed by the Bayesian inference method to reconstruct the phylogenetic relationships between Polychromophilus parasites from bats in Brazil and other countries. Sequences from Brazilian lineages of Polychromophilus were recovered in a clade with sequences from Polychromophilus murinus and close to the one Polychromophilus sequence obtained in Panama, the only available sequence for the American continent. This clade was restricted to bats of the family Vespertilionidae and distinct from Polychromophilus melanipherus, a parasite species mainly found in bats of the family Miniopteridae. The detection of Polychromophilus and the genetic proximity to P. murinus were further confirmed with the amplification of two other genes (clpc and asl). We also found a Haemosporida parasite sequence in a sample of Noctilio albiventris collected in the Pantanal biome, which presents phylogenetic proximity with avian Haemoproteus sequences. Morphological and molecular studies are still needed to conclude and describe the Polychromophilus species in Brazilian Myotis bats in more detail and to confirm Haemoproteus parasites in bats. Nevertheless, these molecular results in Brazilian bats confirm the importance of studying these neglected genera.

Molecular Diagnosis and Prevalence of Trypanosoma vivax (Trypanosomatida: Trypanosomatidae) in Buffaloes and Ectoparasites in the Brazilian Amazon Region.

Trypanosoma vivax Ziemann is a parasite that affects both wild and domestic ungulates and is transmitted mechanically via tabanids and other blood-sucking insects in the Americas. A total of 621 blood samples from water buffaloes (Bubalus bubalis (Linnaeus) (Artiodactyla: Bovidae), and 184 ectoparasite samples (Amblyomma cajennense (Fabricius) sensu stricto and Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae), and Haematopinus tuberculatus (Burmeister) (Phthiraptera: Haematopinidae)) were obtained from 60 farms in the State of Pará, Brazilian Amazon. Twelve buffalo blood samples (1.89%) and 11 ectoparasites (6%) were positive for T. vivax based on the cathepsin L-like gene. All sequences were 99% similar to T. vivax from northeastern Brazil (EU753788) in amplified PCR assays on each of the hosts tested.

Survey of protozoan vector-borne diseases in dogs from Atlantic Rainforest fragment around Billings Dam, São Paulo, Brazil / Levantamento de protozoários transmitidos por vetores em cães de um fragmento de Mata Atlântica nos arredores da Barragem Billings, São Paulo, Brasil

ABSTRACT: Vector-borne diseases are currently one of the biggest public health concerns worldwide. Dogs, being the closest companion animals to humans, are considered the main reservoir of some of these diseases in the urban environment. Therefore, the study of the disease behavior in dogs can help to understand the disease affecting human health. Serological and molecular diagnoses of Babesia vogeli, Rangelia vitalli, Leishmania infantum, and other trypanosomatids, were performed by immunochromatographic and PCR assays, respectively, on dogs in a dog shelter located in an Atlantic Forest fragment near the Billings Dam, São Bernardo do Campo, São Paulo-Brazil. Our molecular diagnostic results showed a high prevalence of Babesia vogeli, at 20.9% (17/81). No other protozoan was detected in any of the tests. Determining the prevalence of major vector-borne diseases is essential to establish preventive and control measures for zoonotic diseases in animals kept in shelters, in order to minimize the impact of vector-borne diseases on animal health.

RESUMO: As doenças transmitidas por vetores são atualmente um dos maiores problemas de saúde pública. Os cães, sendo os animais de companhia mais próximos dos seres humanos, são considerados os principais reservatórios de algumas dessas doenças no ambiente urbano, e o estudo de seu comportamento em cães ajuda a entender a doença como um todo na saúde humana. Diagnósticos sorológicos e moleculares de Babesia vogeli, Rangelia vitalli, Leishmania infantum e outros tripanossomatídeos, em um abrigo para cães localizado em um fragmento da Mata Atlântica próximo à Barragem Billings, São Bernardo do Campo, São Paulo, Brasil. Foram realizadas sorologias e diagnósticos moleculares, no ensaio de PCR foram utilizados marcadores moleculares de oligonucleotídeos específicos para alguns protozoários de importância na saúde animal, como Babesia vogeli, Rangelia vitalli, Leishmania infantum e outros tripanossomatídeos. Nossos resultados de diagnóstico molecular mostraram uma alta prevalência de 20,9% (17/81) de Babesia vogeli. Nenhum outro protozoário foi detectado em nenhum dos testes. A determinação da prevalência das principais doenças transmitidas por vetores é essencial para estabelecer medidas preventivas e de controle de doenças zoonóticas em animais mantidos em abrigos. Essas medidas devem ser propostas para minimizar o impacto de doenças transmitidas por vetores na saúde animal.