Ticks and Tick-borne Diseases 7 (2016) 1139–1145 Contents lists available at ScienceDirect Ticks and Tick-borne Diseases j ourna l h o me page: w ww.elsevier.com/locate/ttbdis Original article First report of “Candidatus Rickettsia amblyommii” in west coast of Mexico Sokani Sánchez-Montes a,b , César A. Ríos-Mu ˜ noz a,b,∗ , Deborah V. Espinosa-Martínez c , Carmen Guzmán-Cornejo d , Miriam Berzunza-Cruz a,b , Ingeborg Becker a,b a Laboratorio de Inmunoparasitología, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Dr. Balmis 148 Col. Doctores, Delegación Cuauhtémoc, C.P. 06726 Ciudad de México, México b Centro de Medicina Tropical, Facultad de Medicina, Universidad Nacional Autónoma de México, Dr. Balmis 148 Col. Doctores, Delegación Cuauhtémoc, C.P. 06726 Ciudad de México, México c Laboratorio de Arqueozoología, Subdirección de Laboratorios y Apoyo Académico, Instituto Nacional de Antropología e Historia, Moneda No. 16, Col. Centro, Delegación Cuauhtémoc, C.P. 06060 Ciudad de México, México d Laboratorio de Acarología, Departamento de Biología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, C.P. 04510 Ciudad de México, México a r t i c l e i n f o Article history: Received 14 February 2016 Received in revised form 1 August 2016 Accepted 14 August 2016 Available online 3 September 2016 Keywords: Amblyomma mixtum Candidatus Rickettsia amblyomii Environmental characteristics Geographic distribution Jalisco Mexico a b s t r a c t We report the first case of “Candidatus Rickettsia amblyommii” detected in Amblyomma mixtum ticks on humans on the west coast of Mexico. This is the most western record of “Ca. R. amblyommii” in the Western Hemisphere, representing the first record for the western coast of the Americas. Even if the record is far from the previously known locations for the species it does not represent a new record regarding temperature, precipitation and topographic parameters. Since “Ca. R. amblyommii” antibodies have been detected in patients suspected of Rocky Mountain spotted fever, and the tick A. mixtum has been associated with humans, it is important to consider “Ca. R. amblyommii” as a potential risk for the human population that has not been considered at risk before. © 2016 Elsevier GmbH. All rights reserved. 1. Introduction Ticks are obligate hematophagous ectoparasites that are associ- ated with a wide range of vertebrate hosts. To date, 896 species are recognized worldwide (Guglielmone et al., 2010), and in Mexico only 100 species have been reported (Pérez et al., 2014). Due to their feeding habits and the wide range of hosts that they can parasitize, ticks are important vectors of several pathogens, especially rickettsiae. The genus Rickettsia encompasses 26 oblig- atory intracellular bacteria that infect arthropods and can cause several diseases in vertebrates (Merhej et al., 2014). In Mexico only five species of rickettsiae, that cause diseases in humans, have been reported: a rickettsial pox agent (Rickettsia akari), two typhus group agents (Rickettsia prowazekii, Rickettsia typhi) and ∗ Corresponding author at: Laboratorio de Inmunoparasitología, Unidad de Inves- tigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Dr. Balmis 148 Col. Doctores, Delegación Cuauhtémoc, C.P. 06726 Ciudad de México, México. E-mail address: cesar.rios@unam.mx (C.A. Ríos-Mu ˜ noz). two spotted fever group agents (Rickettsia felis, Rickettsia rick- ettsii) (Labruna et al., 2011). However, several human cases of spotted fever have been registered without identification of the etiological agent (CENAPRECE, 2015). On the other hand, rickettsial pathogens have been identified in hard ticks including: “Candida- tus Rickettsia amblyommii” in Ambyomma cajennense sensu lato (s. l.) (Medina-Sánchez, 2013; Sosa-Gutierrez et al., 2015); Rick- ettsia prowazekii in Amblyomma cajennense s. l. and in Amblyomma imitator (Medina-Sánchez et al., 2005); Rickettsia rickettsii in Ambly- omma americanum (Sosa-Gutierrez et al., 2015), A. imitator (Oliveira et al., 2010), Amblyomma maculatum (Sosa-Gutierrez et al., 2015), A. cajennense s. l. (Bustamante and Varela, 1946; Sosa-Gutierrez et al., 2015), Amblyomma parvum (Dzul-Rosado et al., 2013), Dermacen- tor nitens (Sosa-Gutierrez et al., 2015) and Rhipicephalus sanguineus (Bustamante and Varela, 1944; Eremeeva et al., 2011; Hoffmann, 1962; Peniche-Lara et al., 2015; Sosa-Gutierrez et al., 2015). Given the increase of recreational activities that are carried out in the wilderness places inhabited by many tick species, it is neces- sary to identify potential rickettsial agents circulating in wildlife that can infect population groups at risk such as people living http://dx.doi.org/10.1016/j.ttbdis.2016.08.007 1877-959X/© 2016 Elsevier GmbH. All rights reserved.