Molecular epidemiology of the emerging zoonosis agent Anaplasma phagocytophilum (Foggie, 1949) in dogs and ixodid ticks in Brazil

Abstract

BackgroundAnaplasma phagocytophilum is an emerging pathogen of humans, dogs and other animals, and it is transmitted by ixodid ticks. The objective of the current study was a) detect A. phagocytophilum in dogs and ixodid ticks using real-time Polymerase Chain Reaction (qPCR); and b) Determine important variables associated to host, environment and potential tick vectors that are related to the presence of A. phagocytophilum in dogs domiciled in Rio de Janeiro, Brazil.MethodsWe tested blood samples from 398 dogs and samples from 235 ticks, including 194 Rhipicephalus sanguineus sensu lato, 15 Amblyomma cajennense, 8 Amblyomma ovale and 18 pools of Amblyomma sp. nymphs. A semi-structured questionnaire was applied by interviewing each dog owner. Deoxyribonucleic acid obtained from ticks and dog buffy coat samples were amplified by qPCR (msp2 gene). The sequencing of 16S rRNA and groESL heat shock operon genes and a phylogenetic analysis was performed. The multiple logistic regression model was created as a function of testing positive dogs for A. phagocytophilum.ResultsAmong the 398 blood samples from dogs, 6.03% were positive for A. phagocytophilum. Anaplasma phagocytophilum was detected in one A. cajennense female tick and in five R. sanguineus sensu lato ticks (four males and one female). The partial sequences of the 16S rRNA, and groESL genes obtained were highly similar to strains of A. phagocytophilum isolated from wild birds from Brazil and human pathogenic strains. The tick species collected in positive dogs were R. sanguineus sensu lato and A. cajennense, with A.cajennense being predominant. Tick infestation history (OR = 2.86, CI = 1.98-14.87), dog size (OR = 2.41, IC: 1.51-12.67), the access to forest areas (OR = 3:51, CI: 1.52-16.32), hygiene conditions of the environment in which the dogs lived (OR = 4.35, CI: 1.86-18.63) and Amblyomma sp. infestation (OR = 6.12; CI: 2.11-28.15) were associated with A. phagocytophilum infection in dogs.ConclusionsThis is the first report of A. phagocytophilum in ixodid ticks from Brazil. The detection of A. phagocitophylum in A. cajennense, an aggressive feeder on a wide variety of hosts, including humans, is considered a public health concern.

Study on coinfecting vector-borne pathogens in dogs and ticks in Rio Grande do Norte, Brazil

“…Multiple pathogens showing zoonotic potential have also been detected in the ticks Ixodes ricinus (A. phagocytophilum, L. infantum and Bartonella henselae) and R. sanguineus (Rickettsia conorii, R. massiliae, L. infantum and A. phagocytophilum) collected from domestic dogs in Europe and South America (TROTTA et al, 2012;PODSIADLY et al, 2007;COLOMBO et al, 2011;SANTOS et al, 2013;SMITH et al, 2013). Dogs parasitized by multiple pathogen-infected ticks may have an unknown clinical outcome that depends on the host-parasite relationship.…”

Important frequency of Anaplasma phagocytophilum infection in a population of domiciled dogs in an urbanized area in south-eastern Brazil

“…Since A. phagocytophilum is widely distributed in the studied area, as indicated by high frequency of residences (62.8%) housing infected dogs, there is a distinct possibility that the agent could be transmitted to pet owners. The only ticks found on the study dogs were R. sanguineus sensu lato and A. phagocytophilum infection was described in these ticks from domesticated dogs in Rio de Janeiro, Brazil (Santos et al 2013 (Krawczak et al 2015). Currently, our research group is conducting an epidemiological investigation in the study area with the aim of (i) determining the pathogenic and zoonotic potential of the isolates of A. phagocytophilum, and (ii) elucidating the biological or mechanical mechanism of transmission of A. phagocytophilum among the canine population.…”

Identificación molecular de hemoparásitos transmitidos por garrapatas en equinos del Noroeste de Colombia

“…En la familia Anaplasmataceae, las especies del género Ehrlichia y Anaplasma se han reportado como los principales patógenos en diferentes especies de mamíferos silvestres y domésticos, incluyendo al hombre (4,5). Dichos géneros afectan diferentes células sanguíneas según la especie, a saber, neutrófilos, monocitos, eritrocitos, macrófagos, plaquetas y células endoteliales de los mamíferos hospederos.…”

“…Dentro del género Anaplasma, desde el punto de vista geográfico, la especie A. phagocytophilum es la más ampliamente distribuida y se ha reportado en Asia, Europa y América (4). A. phagocytophilum es reconocida desde hace mucho tiempo como patógeno en rumiantes domésticos en Europa y equinos en USA, pero recientemente se ha detectado en varias especies de mamíferos, incluyendo los humanos.…”

“…Within the Anaplasmataceae, family, Ehrlichia y Anaplasma have been reported as the main pathogens in various types of wild and domestic mammals, including humans (4,5). Depending on the species, such genuses affect different blood cell types, to wit: neutrophils, monocytes, erythrocytes, macrophages, platelets, and endothelial cells of host mammals.…”