Molecular Detection of Rickettsia parkeri Strain Atlantic Rainforest in Ticks Parasitizing Small Mammals in Northeastern Brazil

An unusual identification ofRickettsia parkeriin synanthropic rodents and domiciliated dogs of a rural community from Yucatán, Mexico

“…Although none of the studied rodents was parasitized by fleas or ticks (data not shown), it is known that small rodents acquire Rickettsia through their ectoparasites (ticks, fleas, and lice) infected with these bacteria (Gajda et al, 2017;Rocha et al, 2022). In the specific case of R. parkeri, the main biological vectors are hard ticks of the genus Amblyomma, which have been associated, especially in pecially, in Yucatán (Arroyo-Ramírez et al, 2022).…”

“…Therefore, in a similar way as with other accidental hosts and carriers of Rickettsia from the study region (Torres‐Castro, Reyes‐Novelo, et al, 2022), the necessary epidemiological elements (biological vectors, reservoirs, and susceptible hosts) exist (Lu et al, 2019) that allow the establishment and circulation of R. parkeri in synanthropic rodent populations such as M. musculus . In this sense, it is accepted that members of the SFG, including R. parkeri , are naturally maintained by vertical and horizontal transmission among the arthropod vectors (ticks) and susceptible vertebrate hosts, respectively (Grasperge, Wolfson, & Macaluso, 2012; Rocha et al, 2022).…”

“…This aspect suggests that dogs and rodents are involved in the same transmission cycle, sharing R. parkeri , which can be explained by the indirect evolutionary cycle and low specificity (more than one host) of Amblyomma ticks (Guglielmone et al, 2003), main vectors of R. parkeri . According to the results presented by Rocha et al (2022) in Brazil, small rodents are carriers of immature stages of A. ovale infected with R. parkeri , which in adult stages, parasitize other larger domestic animals, such as domestic dogs, and even humans, generating the zoonotic transmission cycle of R. parkeri (Labruna et al, 2007; Martiniano et al, 2022).…”

“…Therefore, in a similar way as with other accidental hosts and carriers of Rickettsia from the study region, the necessary epidemiological elements (biological vectors, reservoirs, and susceptible hosts) exist(Lu et al, 2019) that allow the establishment and circulation of R. parkeri in synanthropic rodent populations such as M. musculus. In this sense, it is accepted that members of the SFG, including R. parkeri, are naturally maintained by vertical and horizontal transmission among the arthropod vectors (ticks) and susceptible vertebrate hosts, respectively(Grasperge, Wolfson, & Macaluso, 2012;Rocha et al, 2022). Domestic dogs participate notably in the urban and rural transmission cycles of some Rickettsia species(Dzul-Rosado et al, 2021;Fournier et al, 2020;Torres-Castro et al, 2020;, therefore, they are one of the most studied mammal hosts in Mexico(Sánchez-Montes et al, 2021), es-…”