Isolation ofBorrelia puertoricensisfrom ticks collected in Merida, Yucatan, Mexico

Abstract

Isolation of tick-borne relapsing fever (TBRF) spirochetes has proven to be a useful tool to understand their distribution by geographic areas where the tick vectors inhabit. However, their isolation and culture are not easy and in general an animal model is needed to achieve this task. Here, argasid ticks were collected from a neighborhood in Ciudad Caucel, Merida, Mexico, andBorrelia puertoricensiswas isolated with an immunosuppressed mouse model. By using this model, a higher number of spirochetes were observed in blood samples, and these were successfully cultivated in Barbour-Stoenner-Kelly (BSK)-IIB media. Genomic analyses confirmed that the isolate to beB. puertoricensis. The present report shows that this spirochete is present in argasid ticks in Ciudad Caucel and presents a potential medical and veterinary health risk.Author SummaryRelapsing fever is a neglected disease caused by spirochetes bacteria of theBorreliaand genus that are different than those in the Lyme disease group. These bacteria are transmitted mostly byOrnithodoros(Alectorobious) soft ticks. In many countries, including Mexico,Ornithodorosspecies are understudied and often misidentified. In this report we obtained an isolate ofBorrelia puertoricensisfrom ticks captured in a small park in the city of Merida, Yucatan. These results emphasize the need for fine-scale vector surveillance in neighborhoods to determine the abundance ofBorreliaspecies, and to define their impact on humans and domestic and wild animals.