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Objective: To determine direct and indirect costs associated with raccoon rabies incidents involving cattle herds in Hampshire County, WV, in 2008 and Guernsey County, Ohio, in 2010., Design: Ex post cost analysis., Animals: 1 cattle herd in Hampshire County, WV, in 2008 and 1 cattle herd in Guernsey County, Ohio, in 2010., Procedures: Data were collected for each incident through telephone and email interviews with 16 federal, state, and county agency personnel involved in the case investigations and coordinated responses for rabies in the cattle herds. To characterize the economic impact associated with rabies in the 2 cattle herds, cost analysis was conducted with 7 cost variables (salary and benefits for personnel involved in the response, human postexposure prophylaxis, indirect patient costs, rabies diagnostic testing, cattle carcass disposal, market value of euthanized cattle, and enhanced rabies surveillance). Estimates of direct costs were determined on the basis of agency records and other relevant data obtained from notes and reports made by agency staff at the time of the incident and from a review of the literature., Results: Primary costs included the market value of euthanized cattle ($51,461 in West Virginia; $12,561 in Ohio), human postexposure prophylaxis ($17,959 in West Virginia; $11,297 in Ohio), and salary and benefits for personnel involved in the response ($19,792 in West Virginia; $14,496 in Ohio)., Conclusions and Clinical Relevance: These results should provide a basis for better characterization of the economic impact of wildlife rabies in cattle in the United States.

Oral rabies vaccination (ORV) programs have traditionally relied on tetracycline marking as an index to bait uptake. Whether tetracycline serves well in this capacity depends on its deposition affinity and ability to be detected consistently among tissues selected for analysis from target species. We evaluated samples from 760 hunter-harvested raccoons (Procyon lotor) from areas in Ohio where ORV had been conducted during 1998, 1999, and 2001. Tetracycline marking was evaluated within and among first premolar (PM1), second premolar (PM2), and canine (CN) teeth, and mandibular bone (MB) by side (left versus right); and by tissue type. Tetracycline detection ranged from 6.5% in PM1 in 1998 to 56.3% in right-side MB in 2001. PM1 teeth were less frequently marked (21.7%) than PM2 (27.7%), CN (33.0%), or MB (42.0%). Tetracycline detection was similar in left and right PM1, PM2, and CN teeth, but differed in MB. Tetracycline marking was significantly different among all tissue types.

The effect of different oral rabies vaccine (ORV) bait densities (75, 150, and 300 baits/km(2)) on the seroprevalence of rabies virus neutralizing antibodies (RVNAs) in raccoons (Procyon lotor) was assessed at a 15% seroprevalence difference threshold in rural areas of northeast Ohio. Results (n=588 raccoons) indicated that seropositivity for RVNAs was associated with both bait density and bait campaign frequency. Associations were not detected for raccoon gender, age, or macro-habitat. The odds of being seropositive were greater for raccoons originating from 300 bait/km(2) treatment areas relative to those coming from the 75 bait/km(2) areas (odds ratio [OR]=4.4, probability [P]<0.001, 95% confidence interval [CI]=2.4-7.9), while accounting for cumulative ORV campaigns. No statistical advantage in seroprevalence was detected when comparing 150-75 baits/km(2). These results indicate that a relatively extreme bait density when evenly distributed may be necessary to obtain a significant increase in seroprevalence. Higher bait densities may be more appropriate and less costly to address focused outbreaks than labor intensive trap-vaccinate-release and local population reduction campaigns. Finally, dramatic increases in seroprevalence of RVNA were not observed in raccoons between sequential, semi-annual campaigns, yet cumulative ORV campaigns were associated with gradual increases in seroprevalence.

Research was conducted during 1996-2000 to develop baits for delivering an oral rabies vaccine to raccoons (Procyon lotor) and coyotes (Canis latrans). A bait was sought that: (1) was attractive to the target species, (2) could be distributed by aircraft, (3) was as effective (or more so) than the currently used fish meal polymer bait, and (4) could be produced in large numbers by automated procedures and could be purchased by user groups at substantially lower cost. Ten field trials were conducted to document raccoons' bait flavor preferences, evaluate a new vaccine sachet bait coated with various attractants, and determine if the sachet bait would effectively deliver Raboral V-RG oral rabies vaccine (Merial Limited, Athens, Georgia, USA) to this species. Raccoons preferred fish and crustacean-based flavors over those derived from plant materials. Raccoon visits to tracking stations, frequency of bait removals, and percent of sachets discarded by this species that were emptied of placebo vaccine indicated efficacy of the new bait was equal or superior to the currently used fish meal polymer bait. A field trial conducted in fall 1998 compared aerially distributed vaccine-laden sachet and polymer baits and showed there was no difference between the percent of raccoons from the test and reference areas subsequently found positive for rabies antibody. Four bait trials to determine coyote response to sachet baits were conducted in 1997-98. The propensity for canids to gulp or bolt smaller food items is well known. Thus, a first trial involved offering fish-flavored sachet baits of different sizes to 30 captive coyotes to determine if smaller size baits were more frequently swallowed intact. Two field trials were also conducted in fall 1997 to determine if free-ranging coyotes discriminated among sachet baits coated with different attractants. Finally, Raboral V-RG-laden poultry-flavored sachet baits were aerially dropped and the percent of seropositive coyotes was compared with coyotes from surrounding areas where fish meal polymer vaccine baits had been distributed. Captive coyotes did not swallow sachet baits intact, regardless of size. Bait preference field trials indicated that coyotes preferred poultry, cheese/beef tallow, and fish-flavored sachet baits and that such baits were taken at the same rate as polymer baits. A sample of coyotes from the area baited with vaccine-laden sachet baits had a markedly higher (P = 0.01) seropositivity rate than coyotes from areas where vaccine was distributed in polymer baits. Sachet bait production could be facilitated by automated technology and sachet baits used either as an alternative vaccine delivery device or in combination with the fish meal polymer bait.