Detection of Plague by Testing Serums of Dogs on the Navajo Reservation

Abstract

THE PRESENCE of plague in wild animal populations often is not discovered until a case occurs in man. Frequently, a diagnosis of human plague is not considered until after the patient recovers or dies. This is particularly true when cases of human plague occur in areas where zootic plague has not been previously noted (1). Knowledge of the proximity of wild rodent plague should contribute to earlier consideration of human plague as well as establishment of criteria necessary for control of the zootic source. Recent studies of rodents and carnivores have shown that serologic studies for plague antibodies in these populations may be used to locate infection in wild mammals (2). As early as 1722, it was known that dogs are occasionally infected fatally with Yersinia pestis (3-7). Only since serologic methods have been commonly used has there been evidence indicating that frequently dogs are nonfatally infected. In May 1966 the National Communicable Disease Center and the Division of Indian Health of the Public Health Service began a program of plague surveillance and control on the Navajo Indian Reservation. On this reservation, it was discovered that the domestic dog forages for food in much the same manner as a wild mammal, and a pilot project was initiated to evaluate the testing of dog Mr. Archibald is a public health biologist assigned to the Zoonoses Section, Ecological Investigations Program, Center for Disease Control. Dr. Kunitz is a graduate student at the department of sociology, Yale University, New Haven, Conn. During the time of the fieldwork for this study the authors were in Window Rock, Ariz. Mr. Archibald was with the Zoonoses Section and Dr. Kunitz was a field medical officer for

Annual Seroprevalence ofYersinia pestisin Coyotes as Predictors of Interannual Variation in Reports of Human Plague Cases in Arizona, United States

“…The positive association between human cases and coyote seroprevalence rates was expected because coyotes prey upon plague-susceptible rodents over large areas and typically survive the infection and seroconvert (Archibald and Kunitz 1971, Willeberg et al 1979, Gage et al 1994. It is assumed that passive coyote sampling may detect less noticeable rodent epizootics, which pose a risk to humans from infectious flea bites encountered while outside or brought to the home by their companion animals (Eidson et al 1988, Gould et al 2008.…”

“…Nonetheless, coyotes and other carnivores are potential sentinels of increases in plague activity because of their contact with potentially infectious small mammals and because they often survive plague infection and seroconvert (Archibald and Kunitz 1971, Willeberg et al 1979, Gage et al 1994, Salkeld and Stapp 2006.…”

Differential plague-transmission dynamics determine Yersinia pestis population genetic structure on local, regional, and global scales

“…Sixth, the presence of similar genotypes in prairie dog colonies that are separated by long distances (Ͼ10 km) and unsuitable habitat (e.g., Fig. 2 A, within groups Sitgreaves Mountain, Flagstaff, and San Francisco Peaks) is probably because of intercolony dispersal of plague-infected fleas through domestic dogs, coyotes, or other predator͞scavengers (16,17).…”

Dog‐Associated Risk Factors for Human Plague

“…The role of pet dogs in plague epidemiology has been previously suggested, and several modes of plague transmission from domestic dogs have been hypothesized, especially transport of fleas into the peridomestic environment (Pollitzer, 1954; Archibald and Kunitz, 1971; von Reyn et al., 1977; Poland and Barnes, 1979; CDC, 1988) In this study, we identified two dog‐associated risk factors for human plague: sleeping in the same bed as a pet dog and having a sick dog in the household. This study supports anecdotal observations during case investigations conducted by state and federal health officials, where plague patients frequently noted having slept in the same bed as their pet dog.…”

“…In New Mexico and Colorado, most plague exposures occur in the peridomestic environment (Hull et al., 1986; Eisen et al., 2007). Peridomestic risk factors previously associated with plague include having available sources of rodent food and harbourage (Mann et al., 1979) and exposure to plague‐infected domestic pets (Meyer, 1942; Kartman et al., 1967; Archibald and Kunitz, 1971; von Reyn et al., 1977; Mann et al., 1979; Nelson et al., 1986; Gage et al., 2000). Domestic pets may become infected through predation on infected animals or through flea bites while exploring rodent burrows or nests (Gage et al., 1994).…”