Genetic Diversity of Bartonella subsp. in Mexican Wild Rodents

Abstract

Objectives - The objective of this study was to identify the prevalence of Bartonella variants present in wild rodents from the Mexican states of Jalisco and the Yucatan and asses their implications for public health. Materials and methods - Hearts, blood and blood clots from a total of 100 rodents consisting of nine different species from Yucatan and Jalisco were analysed for the presence of Bartonella using a classical polymerase chain reaction (PCR) targeting the gltA (379-bp) gene region. Results – Blood and blood clot culture let to the isolation in 3-4 days of small gram negative bacilli which were identified as Bartonella spp. based on colony morphology. Although none of the 62 rodents from Jalisco were positive, rodents sampled in Yucatan showed a prevalence of Bartonella of 57.9% (22/38). Yucatan deer mouse (Peromyscus yucatanicus) was the most sampled rodent species (71%) compared to other rodents in Yucatan and accounted for 100% of the positives found in that state. Phylogenetic analysis showed that the 22 genetic variants found in this study were closely related to Bartonella vinsonii subspecies vinsonii (96.89% - 97.52%). One of the genetic variants also had resembling to Bartonella vinsonii subspecies arupensis, a zoonotic Bartonella subspecies. Conclusion - This study provides the evidence that genetic variants closely related to a non-zoonotic subspecies of Bartonella are present in Peromyscus yucatanicus rodents from San José Pituch in the Yucatan state of Mexico. To assess the implications on human health of these genetic variants of Bartonella, further research is necessary.