First Evidence of Ehrlichia minasensis Infection in Horses from Brazil

Abstract

The genus Ehrlichia includes tick-borne bacterial pathogens affecting humans, domestic and wild mammals. Ehrlichia minasensis has been identified in different animal species and geographical locations, suggesting that this is a widely distributed and generalist Ehrlichia. In the present study, we evaluated Ehrlichial infection in 148 Equidae presented to the Medical Clinic Department of a Veterinary Hospital from a midwestern region of Brazil. Blood samples and ticks collected from the animals were tested by Polymerase Chain Reaction (PCR) for the presence of Ehrlichia spp. A multigenic approach including Anaplasmataceae-specific (i.e., 16S rRNA, groEL, gltA) and Ehrlichia-specific (i.e., dsb and trp36) genes was used for accurate bacteria identification. Sera samples were also collected and evaluated for the detection of anti-Ehrlichia antibodies by indirect fluorescent antibody test (IFA). Possible associations between molecular and serological diagnostics and clinical and hematological manifestations were tested using chi-squared or Fisher’s exact tests. Sequence analysis of the dsb fragment revealed that three horses (2.03%) were exposed to E. minasensis. Sixty-one (41.2%) Equidae (58 equines and three mules), were seropositive for Ehrlichia spp., with antibody titers ranging between 40 and 2560. Seropositivity to ehrlichial antigens was statistically associated with tick infestation, rural origin, hypoalbuminemia and hyperproteinemia (p ≤ 0.05). The present study reports the first evidence of natural infection by E. minasensis in horses from Brazil.

First report on tick-borne pathogens detected in ticks infesting stray dogs near butcher shops

“…were detected in ticks in BASDs. In previous studies, E. minasensis has been detected in ticks infesting different hosts, such as cattle, horses, goats, and dogs (44,45). For the genetic characterization of Ehrlichia spp., the 16S rDNA and dsb partial fragments have been identified as accurate genetic markers at the species level (46,47).…”

Tick-borne pathogens identified inHyalomma marginatum(Acari: Ixodidae) collected from various vertebrate hosts in the South of France

“…The distribution of E. minasensis is not restricted to the American continent (Gajadhar et al 2010;Cruz et al 2012;Aguiar et al 2014), and this bacterium was reported recently in Corsica island (Vincent Cicculli et al 2019), in Pakistan (Rehman et al 2019), Ethiopia (Hailemariam et al 2017), South Africa (Iweriebor et al 2017) and Israel (Thomson et al 2018). E. minasensis infects not only bovines (Gajadhar et al 2010;Aguiar et al 2014;Hailemariam et al 2017), cervids (Lobanov et al 2012) or dogs (Thomson et al 2018), but also horses (Muraro et al 2021). Although the vector competence of ticks for this microorganism remains to be tested, E. minasensis has already been identified in several tick species including R. microplus (Cruz et al 2012;Carvalho et al 2016), R. appendiculatus (Iweriebor et al 2017) and H. anatolicum (Rehman et al 2019).…”

Hemoparásitos en equinos de la Unidad de la Policía Montada del Ministerio de Seguridad Pública de Costa Rica

“…El equino PCR positivo a Ehrlichia spp. no mostró alteraciones hematológicas, lo cual difiere con otros estudios, que reportan la anemia como el hallazgo hematológico principal, esto puede deberse a que se tratara de una infección subclínica o que estuviera en el período de incubación de la enfermedad (Muraro et al, 2021;Rivera and Motta, 2013). Finalmente, dos de los tres equinos positivos a B. caballi presentaron anemia e hipoglicemia, mientras que el equino positivo a T. equi presentó anemia, lo cual concuerda con el estudio de Díaz y colaboradores (2018) en Cuba, que reportan, como hallazgo más importante, en infecciones con estos dos agentes, la anemia; además, hay estudios que relacionan la hipoglicemia con babesiosis (Díaz et al, 2018;Naji, 2019).…”