Zoonoses Public Health. 2020;00:1–7. wileyonlinelibrary.com/journal/zph | 1 © 2020 Wiley-VCH GmbH Received: 18 May 2020 | Revised: 13 August 2020 | Accepted: 11 September 2020 DOI: 10.1111/zph.12770 SHORT COMMUNICATION Urban foci of murine typhus involving cat fleas (Ctenocephalides felis felis) collected from opossums in Mexico City Verónica Santoyo-Colín 1 | Sokani Sánchez-Montes 2,3 | Beatriz Salceda-Sánchez 4 | Herón Huerta-Jiménez 4 | Virginia Alcántara-Rodríguez 5 | Ingeborg Becker 2 | Fernando Gual-Sill 1,6,7 | Andrés M. López-Pérez 7,8 Santoyo-Colín and Sánchez-Montes have contributed equally to writing this manuscript 1 Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana –Unidad Xochimilco, Ciudad de México, México 2 Centro de Medicina Tropical, División de Investigación, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, México 3 Facultad de Ciencias Biológicas y Agropecuarias región Tuxpan, Universidad Veracruzana, Veracruz, México 4 Laboratorio de Entomología, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Ciudad de México, México 5 Unidad Departamental de Vigilancia Epidemiológica de la Red de Hospitales de la Ciudad de México, Secretaría de Salud del Gobierno de la Ciudad de México, Ciudad de México, México 6 Dirección General de Zoológicos y Conservación de la Fauna Silvestre, Secretaría del Medio Ambiente de la Ciudad de México, Ciudad de México, México 7 Departamento de Etología, Fauna Silvestre y Animales de Laboratorio, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Ciudad de México, México 8 School of Veterinary Medicine, Department of Medicine and Epidemiology, University of California, Davis, CA, USA Correspondence Fernando Gual-Sill, Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana –Unidad Xochimilco. Calzada del Hueso 1100, Col. Villa Quietud, Alcaldía Coyoacán, CP. 04960, Ciudad de México, México. Emails: fguals@correo.xoc.uam.mx; f.gual. sill@gmail.com Abstract Murine typhus, a neglected rickettsiosis caused by Rickettsia typhi, is a common dis- ease in several Latin-American countries. The sylvatic life cycle of R. typhi encom- passes the presence of several wild mammals, particularly opossums of the genus Didelphis and their associated fleas. Due to the colonization of wild environments by human populations, the increase in contact with opossum fleas has generated the presence of urban outbreaks of typhus. For this reason, the aim of our study was to identify the presence and diversity of Rickettsia sp. in fleas collected from opos- sums of an urban reserve in Mexico City. Opossums were captured from February to September 2017. For the detection of Rickettsia DNA, fragments of 800 bp of the citrate synthase ( gltA) and the outer membrane protein B (ompB) were amplified. A total of 141 fleas (111 ♀, 30 ♂) of a single species (Ctenocephalides felis felis) were re- covered from 31 Didelphis virginiana. Rickettsia DNA was detected in 17.7% (25/141) of the analysed fleas, recovered from seven infested opossums. The Maximum likeli- hood of sequences exhibited an identity of 99%–100% with sequences of R. typhi from southern United States. This work represents the first record of R. typhi in fleas from opossums in Mexico. KEYWORDS Ctenocephalides felis felis, Didelphis virginiana, Flea-borne pathogen, Rickettsia typhi