Animal borne rabies is a source of infection in humans, and raccoons (Procyon lotor) are the primary terrestrial reservoir in West Virginia (WV). To assess the behavior and status of raccoon variant rabies virus (RRV) in WV, a longitudinal analysis for the period [2000][2001][2002][2003][2004][2005][2006][2007][2008][2009][2010][2011][2012][2013][2014][2015] was performed, using data provided by the state Bureau of Public Health. Analytic approaches included linear-mixed, Poisson, and zero inflated Poisson regressions. Each of these approaches indicated that there had been a reduction in numbers of RRV positive animals over the study period, predominantly due to a decrease in raccoon infections.Non-raccoon species did not appear to have a similar decline, however. This has implications for the preventive measures currently being implemented. Spatial analyses of RRV and further examination of the virus in non-raccoon species are warranted. 105 Unfortunately, data are not available regarding how many of these are true exposures (defined as 106 a bite or a scratch), nor is a complete species breakdown of the animals involved available. PeerJ Preprints 107In order to assess the public health risk of rabies to humans in WV and the current state 108 of rabies prevention efforts, the aim of this paper is to determine whether there has been a The Poisson model was fit using log human population density as the offset, yielding a 159 regression coefficient of -0.050 with a p-value of <0.001 and an AIC of 2377.5, as shown in 160 Table 1. This indicates that there is a significant negative trend in RRV numbers and that the 161 model provides an improved fit to the data as compared to the linear mixed model. 162The data appeared highly right skewed, as shown in Figure 1, with substantial numbers of 163 zero values. Once the ZIP model was fit, a regression coefficient of -0.044 was obtained, with a 164 p-value of <0.001 and a 2260.2 AIC. This result was highly significant and resulted in an AIC 165 that indicated improved model fit. In the ZIP model, the coefficient can be interpreted as follows:166 the mean number of cases in log-scale was reduced by 0.044 per year for 16 years, which is 167 equivalent to a reduction of 1.045 cases per year for 16 years. 168Finally, ZIP models were fit for each of the three animal types in this study, and the 169 results are shown in Table 2 There are several potential reasons for the reduction in RRV incidence over the study 212 period. The ORV project is well established in the state, and may be having a significant effect 213 on overall RRV numbers. Additionally, given the rapidly fatal progression of the infection in 214 affected animals, it is possible that the disease is "burning itself out" and has reached, or is 217The temporal pattern of RRV infection in non-raccoon animals may be cause for concern.218 One would anticipate that as numbers of RRV positive raccoons decline, numbers in non-219 raccoon species would experience a similar decline. This is not borne out by the data...

Animal borne rabies virus is a source of infection in humans, and raccoons (Procyon lotor) are the primary terrestrial reservoir in West Virginia (WV). To assess the behavior and status of raccoon variant rabies virus (RRV) cases in WV, a longitudinal analysis for the period 2000–2015 was performed, using data provided by the state Bureau of Public Health. The analytic approach used was negative binomial regression, with exclusion of those counties that had not experienced RRV cases in the study period, and with further examination of those counties where oral rabies vaccine (ORV) baits had been distributed as compared with non-ORV counties. These analyses indicated that there had been a reduction in numbers of RRV positive animals over the study period, predominantly due to a decrease in raccoon infections. Non-raccoon hosts did not appear to have a similar decline, however. The rates of decline for the ORV zone were found to be significantly greater as compared to the non-ORV area. The study was limited by the lack of data for season or point location of animal collection, and by lack of surveillance effort data. Even so, this study has implications for the preventive measures currently being implemented, including expanded vaccination effort in domestic animals. Spatial analyses of RRV and further examination of the virus in non-raccoon hosts are warranted.

Animal borne rabies is a source of infection in humans, and raccoons (Procyon lotor) are the primary terrestrial reservoir in West Virginia (WV). To assess the behavior and status of raccoon variant rabies virus (RRV) in WV, a longitudinal analysis for the period [2000][2001][2002][2003][2004][2005][2006][2007][2008][2009][2010][2011][2012][2013][2014][2015] was performed, using data provided by the state Bureau of Public Health. Analytic approaches included linear-mixed, Poisson, and zero inflated Poisson regressions. Each of these approaches indicated that there had been a reduction in numbers of RRV positive animals over the study period, predominantly due to a decrease in raccoon infections.Non-raccoon species did not appear to have a similar decline, however. This has implications for the preventive measures currently being implemented. Spatial analyses of RRV and further examination of the virus in non-raccoon species are warranted. 105 Unfortunately, data are not available regarding how many of these are true exposures (defined as 106 a bite or a scratch), nor is a complete species breakdown of the animals involved available. PeerJ Preprints 107In order to assess the public health risk of rabies to humans in WV and the current state 108 of rabies prevention efforts, the aim of this paper is to determine whether there has been a The Poisson model was fit using log human population density as the offset, yielding a 159 regression coefficient of -0.050 with a p-value of <0.001 and an AIC of 2377.5, as shown in 160 Table 1. This indicates that there is a significant negative trend in RRV numbers and that the 161 model provides an improved fit to the data as compared to the linear mixed model. 162The data appeared highly right skewed, as shown in Figure 1, with substantial numbers of 163 zero values. Once the ZIP model was fit, a regression coefficient of -0.044 was obtained, with a 164 p-value of <0.001 and a 2260.2 AIC. This result was highly significant and resulted in an AIC 165 that indicated improved model fit. In the ZIP model, the coefficient can be interpreted as follows:166 the mean number of cases in log-scale was reduced by 0.044 per year for 16 years, which is 167 equivalent to a reduction of 1.045 cases per year for 16 years. 168Finally, ZIP models were fit for each of the three animal types in this study, and the 169 results are shown in Table 2 There are several potential reasons for the reduction in RRV incidence over the study 212 period. The ORV project is well established in the state, and may be having a significant effect 213 on overall RRV numbers. Additionally, given the rapidly fatal progression of the infection in 214 affected animals, it is possible that the disease is "burning itself out" and has reached, or is 217The temporal pattern of RRV infection in non-raccoon animals may be cause for concern.218 One would anticipate that as numbers of RRV positive raccoons decline, numbers in non-219 raccoon species would experience a similar decline. This is not borne out by the data...

Background and Objectives: Rabies is an almost invariably fatal viral disease of mammals. In West Virginia, there are two variants of the rabies virus, bat and raccoon. Raccoon rabies (RRV) was introduced subsequent to a release by hunters, and has since spread throughout the Northeastern United States and into Canada. There has been a notable lack of westward movement, however. The objectives of these studies are to 1) examine the behavior of RRV temporally during the study period 2) determine whether there are spatial determinants that may be associated with RRV incidence and 3) examine whether the change of spatial determinants with time over the study period can be correlated with changes in RRV incidence. Secondary objectives included evaluation of the oral rabies vaccine program, determination of whether clustering of disease occurred in the state, and examination of whether there were changes in RRV behavior in varying animal hosts. Methods: County-level surveillance data were obtained from the West Virginia state health department and combined with geographic data from a number of publicly available databases. In the first study, RRV case numbers were examined to determine any trends over the study period, 2000-2015, and trends were compared for counties where oral rabies vaccination had occurred and those without vaccination program implementation, using negative binomial regression techniques and z-score comparisons. The second study evaluated several geospatial characteristics of the counties for association with disease incidence and clustering of disease, using Poisson spatial conditional autocorrelation regression within a Bayesian environment and local indicators of spatial autocorrelation. In the third study, integrated nested Laplace approximation (INLA) and negative binomial regression were utilized to allow simultaneous adjustment for the random effects of both time and space. In each study, analyses were performed for the data as a whole, in addition to analyses of various host subpopulations. Results: Study 1. Analyses found statistically significant (p < 0.05) reductions in case numbers over the study period and showed that incidence rates were declining at significantly higher rates in counties where oral rabies vaccination had been deployed. Incidence showed significant declines for all animals in the study and the raccoon only subpopulation, but similar declines could not be shown in non-raccoon wildlife or domestic animals. Study 2. Statistically significant clustering of RRV cases was demonstrated for all host types examined, with clustering tending to occur in the eastern portion of the state and overlapping for the various host types. Several geospatial variables were shown to be significantly associated (credible intervals did not include 0) with RRV incidence, with several of the variables recurring among the host types. Study 3. Regression analyses that compensated for spatial and temporal autocorrelation showed that many of the variables found to be associated in study 2 did not r...