Leishmania infantum INFECTION IN DOGS FROM THE SOUTHERN REGION OF MINAS GERAIS STATE, BRAZIL

Abstract

SUMMARYVisceral leishmaniasis is a systemic and chronic disease and dogs are the main reservoir of the etiologic agent, Leishmania infantum (syn L. chagasi). A serological and molecular investigation of canine visceral leishmaniasis (CVL) was performed in the municipality of Alfenas, located in the southern region of Minas Gerais, where the disease is not endemic. Samples from 87 dogs were submitted to serological tests including the Dual Path Platform (DPP(r) ) CVL Bio-Manguinhos rapid test, an in-house enzyme-linked immunosorbent assay (ELISA) and an immunofluorescence antibody test (IFAT), as well as molecular techniques such as a conventional polymerase chain reaction (PCR) with the RV1/RV2 primers and a quantitative PCR (qPCR) with the LinJ31, Ldon and DNApol primers. Of the 87 serum samples, eight (9.2%) were positive for Leishmania using the DPP rapid test, but only four (4.6%) were confirmed by ELISA and two (2.3%) by IFAT. In these two serologically confirmed cases, spleen and liver samples were positive by all the employed molecular and parasitological procedures performed on spleen samples. When whole blood samples were used in the molecular assays, two samples (2.3%) were positive only by qPCR. DNA extracted and amplified from the spleens of seropositive dogs was sequenced, showing 100% of similarity with the Leishmania infantum (syn L. chagasi) sequence. Thus, the first cases of CVL have been confirmed in the Alfenas region, suggesting the importance of canine surveys in non-endemic municipalities for CVL to monitor disease progression and to prevent outbreaks.

Elucidating the role played by bone marrow in visceral leishmaniasis

“…In endemic areas of Brazil, the Ministry of Health has estimated that each case of human VL corresponds to at least 200 infected dogs, leading to an estimated 700,000 cases of CVL annually ( da Saúde Mato Grosso do Sul BRASIL M, 2020 ). CVL distribution extends beyond the most prevalent Northeastern region to others, such as the Southeast, with expanding numbers of cases reported in Rio de Janeiro ( Júnior et al., 2015 ), Minas Gerais ( Nunes et al., 2016 ; Ursine et al., 2016 ) and São Paulo ( Oliveira et al., 2016 ) in recent years. In the South, the first cases of CVL were reported in 2008 in Rio Grande do Sul, which preceded the appearance of the first cases recorded in humans in 2009 in the same region ( Da Silva et al., 2011 ; Júnior et al., 2015 ).…”

Comparative Study of a Novel Lateral Flow Rapid Test with Conventional Serological Test Systems for the Diagnosis of Canine Leishmaniosis in Croatia and Brazil

“…In the Americas, Brazil is the country responsible for the endemic disease of leishmaniasis, with 96% of the VL cases occurring in this country. Although surveys that assess the VL/CanL situation in Brazil are scarce, the expansion of cities into forest areas, the high number of domestic dogs and the adaptability of sandflies are likely to be responsible for the spread of leishmaniasis in northeastern municipalities of Brazil [ 12 , 13 , 14 ]. Thus, dogs have become the main target for disease control [ 15 ].…”