{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T17:25:50Z","timestamp":1793467550809,"version":"4.5.0"},"reference-count":42,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2019,7,3]]},"abstract":"<jats:p>An epidemic of Rocky Mountain spotted fever (RMSF) is ongoing in Mexicali, M\u00e9xico. We visited 100 neighborhoods with diagnosed human cases and 100 control neighborhoods to evaluate knowledge of the epidemic; obtain data on the spatial distribution of dogs, canine seroprevalence and active infection, tick infestations, and presence of rickettsial DNA in ticks; and evaluate risk factors for human cases, seropositivity, and tick infestation within an unbiased study design. The majority (80%) of residents had heard of RMSF, but only 48% used acaricides in the home or on dogs. Case neighborhoods and those with high canine seroprevalence tended to be on the city periphery or in the agricultural valley. No dogs were polymerase chain reaction (PCR) positive for <jats:italic>Rickettsia rickettsii<\/jats:italic>, and the overall seroprevalence was 65% (titers from 64 to 1,024). PCR prevalence in ticks was 0.70%, confirmed by DNA sequencing as <jats:italic>R. rickettsii<\/jats:italic>; neighborhood prevalence ranged from 0.7% to 6.1%. Twelve percent of dogs had high tick burdens, and all ticks were <jats:italic>Rhipicephalus sanguineus<\/jats:italic>. Epidemiologically significant risk factors were ground covering for a neighborhood having a human case; dogs having poor body condition and weighing &lt; 10 kg for canine seropositivity; dogs living at the home for the number of ticks in the environment; and being near canals, having trash on the patio, and a dog being thin for tick burdens on dogs. A One Health approach is crucial to understanding RMSF and brown dog ticks.<\/jats:p>","DOI":"10.4269\/ajtmh.18-0878","type":"journal-article","created":{"date-parts":[[2019,5,14]],"date-time":"2019-05-14T07:01:02Z","timestamp":1557817262000},"page":"22-32","source":"Crossref","is-referenced-by-count":41,"title":["Unbiased Assessment of Abundance of Rhipicephalus sanguineus sensu lato Ticks, Canine Exposure to Spotted Fever Group Rickettsia, and Risk Factors in Mexicali, M\u00e9xico"],"prefix":"10.4269","volume":"101","author":[{"given":"Janet","family":"Foley","sequence":"first","affiliation":[{"name":"Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Tinoco-Gracia","sequence":"additional","affiliation":[{"name":"Laboratorio de Salud P\u00fablica Veterinaria, Instituto de Investigaciones en Ciencias Veterinarias, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moises","family":"Rodriguez-Lomel\u00ed","sequence":"additional","affiliation":[{"name":"Facultad de Medicina, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Estrada-Guzm\u00e1n","sequence":"additional","affiliation":[{"name":"Facultad de Medicina, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Fierro","sequence":"additional","affiliation":[{"name":"Public Health Department, Imperial County, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elva","family":"Mattar-Lopez","sequence":"additional","affiliation":[{"name":"Facultad de Medicina, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amy","family":"Peterson","sequence":"additional","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily","family":"Pascoe","sequence":"additional","affiliation":[{"name":"Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yolanda","family":"Gonzalez","sequence":"additional","affiliation":[{"name":"Laboratorio de Salud P\u00fablica Veterinaria, Instituto de Investigaciones en Ciencias Veterinarias, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sawako","family":"Hori-Oshima","sequence":"additional","affiliation":[{"name":"Laboratorio de Salud P\u00fablica Veterinaria, Instituto de Investigaciones en Ciencias Veterinarias, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paige A.","family":"Armstrong","sequence":"additional","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gilberto","family":"Lopez","sequence":"additional","affiliation":[{"name":"Laboratorio de Salud P\u00fablica Veterinaria, Instituto de Investigaciones en Ciencias Veterinarias, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariana","family":"Jacome-Ibarra","sequence":"additional","affiliation":[{"name":"Laboratorio de Salud P\u00fablica Veterinaria, Instituto de Investigaciones en Ciencias Veterinarias, Universidad Aut\u00f3noma de Baja California, Mexicali, M\u00e9xico;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher D.","family":"Paddock","sequence":"additional","affiliation":[{"name":"Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oscar E.","family":"Zazueta","sequence":"additional","affiliation":[{"name":"Direcci\u00f3n de Ense\u00f1anza y Vinculaci\u00f3n, Instituto de Servicios de Salud P\u00fablica del Estado de Baja California, Mexicali, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"key":"b1","series-title":"MMWR Recomm Rep","first-page":"1","article-title":"Diagnosis and management of tickborne rickettsial diseases: Rocky Mountain spotted fever and other spotted fever group rickettsioses, ehrlichioses, and anaplasmosis\u2014United States","volume":"65","author":"Biggs","year":"2016"},{"key":"b2","series-title":"Ann N Y Acad 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