Trypanosoma (Herpetosoma) diversity in rodents and lagomorphs of New Mexico with a focus on epizootological aspects of infection in Southern Plains woodrats (Neotoma micropus)

First report of Trypanosoma microti in Cricetid rodents from Querétaro, Mexico: Expanding the known distribution of Herpetosoma in the Mexican transition zone

Members of the subgenus Herpetosoma are specialized parasites of mammals of the order Lagomorpha and Rodentia. It is estimated that around 50 species within this subgenus are transmitted by several flea species. These parasites have recently gained attention from a public health perspective because several species have been reported to infect humans. Several species of the Herpetosoma subgenus have been recognized on the American continent, although there have been no reports from the Mexican Transition Zone. Therefore, the present study aimed to report the presence of a member of the Herpetosoma subgenus in cricetid rodents from Querétaro, Mexico. A total of 17 rodents belonging to three species, Peromyscus boylii, Peromyscus gratus, and Peromyscus melanophrys, were collected. Genetic material was extracted using the Chelex 100 resin, followed by PCR and sequencing of a fragment of 800 bp of the 18S ribosomal gene of the genus Trypanosoma. Out of these hosts, eight individuals of P. gratus (1♀), P. melanophrys (1♂), and P. boylii (3♂, 3♀) tested positive for Trypanosoma microti DNA, previously detected in the England and Japan. The present study, therefore, provides the first discovery of T. microti in Mexico, thereby increasing the known richness of species of the genus Trypanosoma in rodents from this country and the Mexican Transition Zone.

Current Status of Trypanosoma grosi and Babesia microti in Small Mammals in the Republic of Korea

Small mammals, such as rodents and shrews, are natural reservoir hosts of zoonotic diseases, including parasitic protozoa. To assess the risk of rodent-borne parasitic protozoa in the Republic of Korea (ROK), this study investigated the status of parasitic protozoa, namely Trypanosoma, Babesia, and Theileria, in small mammals. In total, 331 blood samples from small mammals were analyzed for parasites using PCR and sequenced. Samples were positive for Trypanosoma grosi (23.9%; n = 79) and Babesia microti (10%; n = 33) but not Theileria. Small mammals from Seogwipo-si showed the highest infection rate of T. grosi (48.4%), while the highest B. microti infection rate was observed in those from Gangneung-si (25.6%). Sequence data revealed T. grosi to be of the AKHA strain. Phylogenetic analysis of B. microti revealed the US and Kobe genotypes. B. microti US-type-infected small mammals were detected throughout the country, but the Kobe type was only detected in Seogwipo-si. To our knowledge, this is the first nationwide survey that confirmed T. grosi and B. microti infections at the species level in small mammals in the ROK and identified the Kobe type of B. microti. These results provide valuable information for further molecular epidemiological studies on these parasites.