Antimicrobial resistance in Escherichia coli isolates from raccoons (Procyon lotor) in Southern Ontario, Canada.

We conducted a cross-sectional study to determine the prevalence of antimicrobial resistance (AMR) in fecal Escherichia coli isolates from raccoons (Procyon lotor) living in Ontario, Canada. From June to October 2007, we trapped raccoons in three areas: one primarily urban site around Niagara, one primarily rural site north of Guelph, and one at the Toronto Zoo. In addition, we conducted a longitudinal study at the Toronto Zoo site to investigate the temporal dynamics of fecal E. coli and AMR in raccoons. Reduced susceptibility to ≥1 antimicrobial agent was detected in E. coli isolates from 19% of 16 raccoons at the urban site, 17% of 29 raccoons from the rural site, and 42% of 130 samples collected from 59 raccoons at the zoo site. Raccoons from the zoo site were significantly more likely to shed E. coli with reduced susceptibility to ≥1 antimicrobial agent than animals from the rural site (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.17 to 12.09; P = 0.02). Resistance to expanded-spectrum cephalosporins (and the associated bla(CMY-2) gene) was detected in two animals from the zoo site and one animal from the rural site. Serotyping and pulsed-field gel electrophoresis analysis show that raccoons on the zoo grounds harbor a diverse assemblage of E. coli, with rapid bacterial turnover within individuals over time. Our study indicates that raccoons may shed resistant bacteria of public health significance and that raccoons have the potential to disseminate these bacteria throughout their environment.

Rabies in vaccinated raccoons from Ontario, Canada.

From 1999 to 2006, 132 cases of raccoon rabies, caused by the raccoon variant of rabies virus, were confirmed in eastern Ontario, Canada. Trap-vaccinate-release (TVR) and point infection control (PIC) programs were implemented to control the disease; 43,014 raccoons (Procyon lotor) were vaccinated against rabies by injection (Imrab3) during that period. Two vaccinated raccoons were diagnosed with rabies at 6 mo and at 2 wk postvaccination. One may have been due to a vaccination failure. The other was likely due to the animal being in the late stages of incubation for rabies at the time of vaccination. This information will be useful to wildlife rehabilitators and agencies that hold raccoons in captivity in that a vaccinated raccoon is not necessarily immune to rabies.

The elimination of raccoon rabies from Wolfe Island, Ontario: animal density and movements.

During 1996 to 1998, an average of 52% to 55% of the raccoon (Procyon lotor) population on Wolfe Island, Ontario was vaccinated against rabies during proactive trap-vaccinate-release (TVR) operations. However, during 1999, the percent of the population vaccinated declined to 39% and an outbreak (6 cases) of raccoon rabies occurred on the island from December 1999 to January 2000. The raccoon population on Wolfe Island declined dramatically (71% reduction) from 1,067 raccoons (mean density = 8.4/km(2) [6.4-12.4, 95% CI]) during 1999 to 305 raccoons (mean density = 2.4/km(2) [0.87-4.1, 95% CI]) in the spring of 2000. Raccoon density immediately following the outbreak was significantly lower in cells with rabies cases, suggesting that rabies had a negative effect on population size. However, raccoon density had doubled by 1 yr following the outbreak. Movement of raccoons on Wolfe Island was as great as 24 km. Male raccoons moved greater distances than females. Movements to surrounding islands were also noted for raccoons ear tagged on Wolfe Island which indicates the island could serve as a focus for greater geographic rabies spread. Point infection control (PIC) during 2000, TVR during 2001-02, and the aerial distribution of Vaccinia-Rabies Glycoprotein (V-RG) baits during 2000 and 2003-05 were used to eliminate rabies from Wolfe Island. No cases have been detected since late January 2000 (to February 2007).

Behavior, movements, and demographics of rabid raccoons in Ontario, Canada: management implications.

During 1999-2003, 127 cases of raccoon variant rabies were reported in raccoons (Procyon lotor) and striped skunks (Mephitis mephitis) in Ontario, Canada. Raccoons accounted for 98% (125/127) of the reported cases with behaviors/conditions including aggression, fighting with dogs, ataxia, vocalizations, appearance of being sick, and the presence of porcupine (Erethizon dorsatum) quills. Seventy-eight percent of the rabid raccoons were adults. Juveniles were underrepresented (22%) compared with the adult/juvenile ratios found in nonrabid Ontario raccoon populations. Of the known aged raccoons, 83% were < or = 3 yr of age, and 22% of the rabid adult female raccoons had evidence of having had a litter during the year in which they were found to be rabid. The majority of rabid raccoons were reported during the fall, winter, and spring, suggesting a relationship between raccoon behavioral activities such as denning and breeding and the timing of rabies outbreaks. Multiple cases of raccoon rabies occurred at several barns, suggesting that those structures serve as focal points of rabies transmission as a result of denning activities. Movements of five rabid raccoons (range 1,564-4,143 m) were not different from movements of nonrabid raccoons in Ontario. Sixty-six percent of the rabid animals were submitted by government staff, stressing the importance of those agencies in rabies control and surveillance operations. Increased knowledge of the behaviors of rabid raccoons should assist in the development of management strategies for rabies.

Salmonella in raccoons (Procyon lotor) in southern Ontario, Canada.

Numerous serotypes of Salmonella have been detected in a variety of wild animals, including raccoons (Procyon lotor). Raccoons are common, mid-size omnivores that live in close association with people in urban and rural areas in Ontario. Although raccoons are known to shed Salmonella, little is known about their potential long-term role in maintaining Salmonella infections. We sampled feces from raccoons in three areas of Ontario: one primarily urban site around Niagara, one primarily rural site north of Guelph, and the grounds of the Toronto Zoo, in 2007 to identify which serotypes of Salmonella were commonly shed by raccoons in southern Ontario. In addition, we conducted a longitudinal study at the Toronto Zoo site to determine if raccoons remain persistently infected with Salmonella. Salmonella was found in 45% of samples. The prevalence of Salmonella in raccoon feces ranged from 27% at the rural site to 65% at the urban site. We detected 16 serotypes of Salmonella in 83 positive samples. The most common serotype detected in raccoons from the rural and zoo sites was Salmonella enterica serotype Typhimurium, whereas Salmonella Newport was detected most commonly in the urban site. Only one raccoon of 11 that were captured in four or more consecutive trapping sessions shed the same Salmonella serotype for two consecutive months, suggesting that raccoons regularly acquire new Salmonella serotypes from the environment.