COYOTES (CANIS LATRANS) IN ARIZONA, USA, EXHIBIT IMMUNE AND GENETIC EVIDENCE OF RICKETTSIAL INFECTIONS.

Rocky Mountain spotted fever (RMSF), caused by the bacterium Rickettsia rickettsii, was recognized as endemic in Arizona, US after a 2002 outbreak and has since been a public health concern. The brown dog tick (Rhipicephalus sanguineus sensu lato) is the principal vector of this pathogen in Arizona. Domesticated dogs (Canis lupus familiaris) are the tick's main host, so free-roaming dogs in peridomestic areas have been named the primary risk factor for human cases of RMSF. However, the sudden emergence and long-distance dispersal of the pathogen have not been adequately explained, and one possible mechanism could include wildlife. Coyotes (Canis latrans) are wide ranging in Arizona and closely related to dogs, so it is possible that brown dog ticks parasitize coyotes and infect them. Although R. rickettsii is the most severe spotted fever group (SFG) rickettsial pathogen in humans, others occur in Arizona, and antibodies raised against them are cross-reactive, so we more-broadly hypothesized that coyotes in Arizona are exposed to SFG rickettsiae. We collected coyote tissues in spring 2016 and 2017. We tested sera for antibodies to R. rickettsii and found 9% (8/94) of samples were antibody-positive with titers of ≥256. Subsequent quantitative PCR analyses of skin showed evidence for Rickettsia spp. in 2.9% (4/138) of samples. These data suggest that coyotes have a role in the maintenance of SFG rickettsiae in Arizona. Further investigation is warranted to reveal which specific pathogen-vector complexes act on coyotes in the region and whether they represent a risk to human health.

Population survey and management strategies of free-roaming dogs (Canis familiaris) on Saipan, Commonwealth of the Northern Mariana Islands.

The island of Saipan, Commonwealth of the Northern Mariana Islands, is populated by free-roaming dogs who were introduced during World War II. The local nonhuman animal control agency manages this population; however, the demographic information and public perception of this population remain unknown. To characterize the free-roaming dog population, an island-wide survey on Saipan was conducted. Photographic, mark-recapture data were used to estimate the population size per land type. Age, sex, sociality, and behavior per land type were documented and associations between these variables were tested using G tests. The effects of land type and urbanization on dog abundance were also analyzed. Lastly, in-person surveys provided data on the public perception of free-roaming dogs. Four main findings are reported: (a) The population size of free-roaming dogs on Saipan is estimated at 21,316. (b) Most dogs encountered were sentry adults. (c) Dog abundance increased with urbanization level and was highest in urban areas. (d) The public perceived free-roaming dogs as a health concern and suggested the implementation of leash laws and sheltering initiatives. This article discusses potential and existing population management strategies for free-roaming dogs on Saipan.