Efficient distribution of oral vaccines examined by infrared triggered camera for advancing the control of raccoon dog rabies in South Korea

The field distribution of the oral rabies vaccine is effective in controlling the spread of rabies. The present study aimed to investigate efficient distribution locations based on the environment, contact rate, and consumption by target wildlife species in South Korea. The target species (Korean raccoon dogs, domestic dogs, and feral cats) accounted for 945 contacts (52.2%), in total 1,808 contacts. There were 863 (47.8%) contacts by non-target species. Raccoon dogs, a main reservoir of rabies in South Korea, had the highest contact rate (34.1%) among all species. The contact rate by target species was highest at riparian sites and bushy mountainous vegetation, where raccoon dogs are abundant. There was remarkable contact by raccoon dogs in mountainous areas below 150 m with bushy vegetation. Our results indicate that these locations are efficient areas for vaccine distribution, especially targeting the raccoon dog. Vaccines were continuously contacted with intervals ranging from one hour to one day. Vaccines at 94.4% of the distribution points were completely consumed within two weeks. The mean consumption rate was 95.2 ± 1.93% during the overall study period. These findings suggest that the oral rabies vaccine attracts wildlife including domestic dogs and feral cats. Our results suggest that low sections of mountainous areas with bushy vegetation and/or neighboring riparian areas are rich in target wildlife species (especially raccoon dogs) and are efficient locations for vaccine distribution to control rabies in South Korea.     

Challenges to controlling rabies in skunk populations using oral rabies vaccination: A review

Controlling rabies in skunk populations is an important public health concern in many parts of the United States due to the potential for skunk rabies outbreaks in urban centres and the possible role for skunks in raccoon rabies variant circulation. Oral rabies vaccination (ORV) programmes have supported wildlife rabies control efforts globally but using ORV to control rabies in skunk populations has proven more challenging than with other target species, like foxes, coyotes and raccoons. A review of published studies found that some ORV constructs are immunogenic in skunks and protect against virulent rabies virus challenges, especially when delivered by direct installation into the oral cavity. However, in field ORV programmes using currently available vaccine‐bait formats and distribution methods targeting other rabies reservoir species, skunks often fail to seroconvert. Field effectiveness of ORV in skunks appears to be limited by poor bait uptake or inadequate ingestion of vaccine rather than from poor vaccine efficacy. Observations of captive skunks revealed vaccine spillage when handling and biting into baits such that modification of bait formats might improve field effectiveness. In addition, a dose–response relationship between bait distribution density and post‐baiting seroconversion among skunks was observed across the limited number of field studies. Additional research is needed to identify opportunities to modify ORV baits and distribution strategies to improve the viability of ORV as a rabies control strategy in skunks.     

Rabies, an emerging disease in Korea

Since the first rabies case was reported in a dog in 1907, the disease was enzootic up to 1975 in Korea. After a steady decrease in the number of rabies cases from 1976 to 1984, no case was reported for 8 years from 1985 to 1992. Then, a resurgence of the disease was noted in 1993, and a continuous increase of rabies cases was observed during the following years. This report provides information on rabies in South Korea during the reemerging period 1993-2003. A total of 364 rabies cases in five different animal species and five deaths in human beings as a result of rabies were reported. Cattle and dogs accounted for 46.4% and 40.4% of total animal cases, respectively, and raccoon dogs commanded an overwhelming majority (44/48) of rabies cases in wildlife animal species. All animal and human rabies cases occurred only in two provinces, Gyeonggi and Gangwon; majority of them in two counties of Gyeonggi and one county of Gangwon province that border the demilitarized zone. From the three counties, the disease continued to expand to the other areas of the two provinces. The average monthly frequency of animal rabies cases during the 11-year period peaked in January, and the incidence was highest during winter. There were three major rabies outbreaks in animals and the number of animal rabies cases increased with time. Data indicate that the temporal patterns were attributable to the ethology of raccoon dogs in the areas of outbreak.     

Persistence of elevated rabies prevention costs following post-epizootic declines in rates of rabies among raccoons (Procyon lotor)

Determining the benefits to cost relationships among different approaches to rabies control and prevention has been hindered by the inherent temporal variability in the dynamics of disease among wildlife reservoir hosts and a tangible and objective measure of the cost of rabies prevention. A major and unavoidable component of rabies prevention programs involves diagnostic testing of animals and the subsequent initiation of appropriate public health responses. The unit cost per negative and positive diagnostic test outcome can be reasonably estimated. This metric when linked to methodologies subdividing the epizootic process into distinct temporal stages provided the requisite detail to estimate benefits derived from rabies control strategies. Oral rabies vaccine (ORV), for prevention of the raccoon-associated variant of rabies, has been distributed in Ohio and adjoining states in an effort to develop an immune barrier to the westward spread of epizootic raccoon rabies. The costs of ORV delivery have been quantified. Herein, the cost structures required to assess the benefits accrued by prevention were developed. A regression model was developed effectively predicting (r² = 0.70) the total number of rabies diagnostic tests performed by 53 counties in five northeastern (NE) states from 1992 to 2001. Five temporal stages sufficed to capture the range of variability in the raccoon rabies epizootic process. Unit costs, dollars per diagnostic test outcome, were calculated for negative and positive results from published reports. Ohio counties were matched to NE counties based on similar socioeconomic characters. A “pseudo-epizootic” of raccoon rabies was introduced into Ohio and the costs savings from ORV were derived as the excess costs imposed by epizootic spread throughout the state. At 46 km/year (range modeled, 30–60 km/year), the pseudo epizootic spread, and reached the enzootic stage, in all Ohio counties by year 13 (range modeled, 11–17 years). Cumulative excess costs for Ohio ranged between $11 and $21 million; counties of low socioeconomic status experienced the greatest relative excess costs. The costs for rabies prevention activities reached apices during the epizootic stage of raccoon rabies (2.7–10.8 times baseline) an unforeseen finding indicated elevated costs persisted (1.7–7.2 times baseline) into the enzootic stage.     

Assessing a landscape barrier using genetic simulation modelling: implications for raccoon rabies management

Landscape barriers influence movement patterns of animals, which in turn, affect spatio-temporal spread of infectious wildlife disease. We compare genetic data from computer simulations to those acquired from field samples to measure the effect of a landscape barrier on raccoon (Procyon lotor) movement, enabling risk assessment of raccoon rabies disease spread across the Niagara River from New York State into Ontario, an area currently uninfected by rabies. An individual-based spatially explicit model is used to simulate the expansion of a raccoon population to cross the Niagara River, for different permeabilities of the river to raccoon crossings. Since the model records individual raccoon genetics, the genetic population structure of neutral mitochondrial DNA haplotypes are characterised in the expanding population, every 25 years, using a genetic distance measure, phi ST, Mantel tests and a gene diversity measure. The river barrier effect is assessed by comparing genetic measures computed from model outputs to those calculated from 166 raccoons recently sampled from the same landscape. The "best fit" between modelled scenarios and field data indicate the river prevents 50% of attempts to cross the river. Founder effects dominated the colonizing genetic population structure, and, as the river barrier effect increased, its genetic diversity decreased. Using gene flow to calibrate the effect of the river as a barrier to movement provides an estimate of the effect of a river in reducing the likelihood of cross-river infection. Including individual genetic markers in simulation modelling benefits investigations of disease spread and control.     

Rabies surveillance in the United States during 2002

During 2002, 49 states and Puerto Rico reported 7,967 cases of rabies in nonhuman animals and 3 cases in human beings to the Centers for Disease Control and Prevention, an increase of 7.2% from the 7,436 cases in non-human animals and 1 case in a human being reported in 2001. More than 92% (7,375 cases) were in wild animals, whereas 7.4% (592) were in domestic species (compared with 93.3% in wild animals and 6.7% in domestic species in 2001). Compared with cases reported in 2001, the numbers of cases reported in 2002 increased among all major reporting groups with the exception of swine and rodents and lagomorphs. The relative contributions of the major groups of animals were as follows: raccoons (36.3%; 2,891 cases), skunks (30.5%; 2,433), bats (17.2%; 1,373), foxes (6.4%; 508), cats (3.8%; 299), dogs (1.2%; 99), and cattle (1.5%; 116). Thirteen of the 19 states in which the raccoon-associated variant of the rabies virus has been enzootic reported increases in the numbers of rabid raccoons during 2002. Among those states that have engaged in wildlife rabies control programs, Ohio reported 1 case of raccoon rabies associated with the epizootic of rabies in raccoons and 1 case in an equid that was infected with a bat variant of the rabies virus, compared with 2 cases reported in terrestrial animals during 2001. Texas reported no cases of rabies associated with the dog/coyote variant of the rabies virus (compared with 1 case in 2001) and 65 cases associated with the gray fox variant of the virus (an increase of 225% from 20 cases reported in 2001). In Massachusetts and Rhode Island, states with enzootic raccoon rabies, reports of rabid skunks again exceeded those of rabid raccoons (the sixth consecutive year, although in Rhode Island, this difference decreased to only 7 more skunks than raccoons [38/31]). Tennessee reported a single case of raccoon rabies in a pet raccoon from the central part of the state; the captive animal had been transported toTennessee from northern Georgia. Nationally, the number of rabies cases in skunks during 2002 increased by 6.6% over those reported in 2001. Texas reported the greatest number (740) of rabid skunks and the greatest overall state total of rabies cases (1,049) during 2002. The 1,373 cases of rabies reported in bats during 2002 surpassed the previous year's record (1,281 cases) as the largest number of reported cases ever recorded for this group of mammals. Cases of rabies reported in cats (299), cattle (116), and dogs (99) increased by 10.7%, 41.5%, and 11.24%, respectively, from 2001 to 2002. Rabies among sheep and goats increased 400% from 3 cases in 2001 to 15 in 2002, and cases among horses and mules increased 13.7% (51 cases in 2001 to 58 in 2002). Reported cases of rabies in mongooses in Puerto Rico decreased 4.3% from the previous year (70 cases in 2001 to 67 cases in 2002), while cases of rabies in dogs increased 77% (13 to 14). California, Tennessee, and Iowa each reported a case of rabies in a human being during 2002. All cases of rabies in humans were the result of infection with bat variants of the rabies virus.     

Epidemiological situation of rabies in Lithuania from 1990 to 2000

The epidemiological situation of rabies was investigated in Lithuania. Over the last decade, 2277 cases of rabies were registered among wild and domestic animals (mean number of cases per districts was 44). The highest distribution of rabies was found in the districts of Lazdijai and Utena (116 and 81 cases, respectively), and the lowest in the Svencioniai and Zarasai districts (one and eight cases, respectively). It was found that rabies among wildlife comprised 54% with the majority of cases being registered in foxes (626 cases, 27%) followed by raccoon dogs (470 cases, 21%). Within the last 3 years, cases of rabies among foxes and raccoon dogs increased significantly (three and six times, respectively), compared with the period from 1990 to 1997. Among domestic animals, 46% cases of rabies were registered, with cattle comprising 27%, and the cases among cats and dogs at 9 and 8%, respectively. During the period from 1993 to 1997 in Lithuania, 11,385 of humans were attacked by domestic and wild animals, and 21,173 humans were vaccinated against rabies for prophylactic reasons. Our survey has shown that, during the period from 1997 to 2000, the number of people attacked has increased drastically-31,348 (60%), but only 8021 (18%) of them were vaccinated.     

The raccoon dog (Nyctereutes procyonoides) in Germany--an established Neozoon as host and vector for parasites and other pathogenes

Some invasive wildlife species have the potential to act as additional host and vector species for parasitic and other infectious diseases. We used the raccoon dog (Nyctereutes procyonides), a carnivore species that has its origin in Asia, as an example to demonstrate biological and ecological prerequisites which enables an invasive species to occupy a new habitat permanently. Studies conducted during the last ten years identified a total of 23 endoparasites, two ectoparasites, six bacterial or protozoan species and five viruses, found in the Nyctereutes procyonoides ussuriensis subspecies in its newly occupied range or in N. procyonoides koreensis in its original range. Results of studies in Finland and Germany furthermore showed that biological characteristics of the raccoon dog make this carnivore an appropriate host or vector for a variety of parasites and infectious diseases. This may result in a growing importance of this invasive carnivore for the epidemiology of transmissible diseases in Germany. Especially with regard to zoonotic disease outbreaks, the raccoon dog should therefore be paid more attention in disease prevention and eradication strategies.     

Animal-based national surveillance for zoonotic disease: quality, limitations, and implications of a model system for monitoring rabies

Surveillance for zoonotic diseases among wildlife is a research and public health challenge. The inherent limitations posed by the requisite human–animal interactions are often undefined and underappreciated. The national surveillance system for animal rabies in the United States was examined as a model system; reporting of animal rabies is legally mandated, each case of rabies is laboratory confirmed, and data have been consistently collected for more than 50 years. Factors influencing the monthly counts of animal rabies tests reported during 1992–2001 were assessed by univariate and multivariable regression methods. The suitability of passively collected surveillance data for determining the presence or absence of the raccoon-associated variant of rabies within states and within individual counties was assessed by determining critical threshold values from the regression analyses. The size of the human population and total expenditures within a county accounted for 72% and 67%, respectively, of the variance in testing. The annual median number of rabies tests performed was seven for counties without rabies, 22 for counties with non-raccoon rabies, and 34 for counties with raccoon rabies. Active surveillance may be required in locales with sparse human populations when a high degree of confidence in the status of rabies is required.     

Rabies

The practicing veterinarian has a key role to play in rabies control in the maintenance of protection in the companion animal populations, in the education of the pet-owning community on rabies, and in the decision-making process that accompanies human exposure to potentially rabid animals. This role encompasses far more than the routine maintenance of health and well-being in pet animal populations. Although it is important to remain diligent in the immunization of domestic pets against rabies to provide a barrier between wildlife, the main reservoir of infection, and man, it is also important to be aware of the current trends in wildlife rabies within a region. Research is currently underway to investigate methods of immunizing wildlife populations, but the effective and widespread control of rabies in these species is still a long way off; in the meantime, there will be an increasing demand for practicing veterinarians to take the lead in the control of this most fearful zoonotic disease.     

Raccoon dog rabies surveillance and post-vaccination monitoring in Lithuania 2006 to 2010

Background

Oral rabies vaccination (ORV) in rabies infected regions should target the primary rabies vector species, which in Lithuania includes raccoon dogs as well as red foxes. Specific investigations on ORV in raccoon dogs are needed e.g. evaluation of vaccine effectiveness under field conditions. The objective of the current study was to investigate the efficacy of the ORV programme 2006-2010 in Lithuania by examining the number of rabies cases and estimating the prevalences of a tetracycline biomarker (TTC) and rabies virus antibodies in raccoon dogs.

Methods

From 2006 to 2010, 12.5 million rabies vaccine-baits were distributed by aircraft. Baiting occurred twice per year (spring and autumn), targeting raccoon dogs and red foxes in a 63,000 km² area of Lithuania. The mandibles of raccoon dogs found dead or killed in the vaccination area were analyzed by fluorescence microscopy for the presence of the TTC. Rabies virus sera neutralizing anti-glycoprotein antibody titres were determined using an indirect ELISA method and seroconversion (> 0.5 EU/ml) rates were estimated.

Results

During the study period, 51.5% of raccoon dog mandibles were positive for TTC. 1688 of 3260 tested adults and 69 of 175 tested cubs were TTC positive. Forty-seven percent of raccoon dog serum samples were positive for rabies virus antibodies. 302 of 621 investigated adults and 33 of 95 investigated cubs were seropositive. In the same time 302 of 684 and 43 of 124 tested samples were TTC and ELISA positive in spring; whereas 1455 of 2751 and 292 of 592 tested samples were TTC and ELISA positive in autumn. There was a positive correlation between the number of TTC and antibody positive animals for both adult and cub groups.

Conclusions

ORV was effective in reducing the prevalence of rabies in the raccoon dog population in Lithuania. The prevalence of rabies cases in raccoon dogs in Lithuania decreased from 60.7% in 2006-2007 to 6.5% in 2009-2010.     

An epidemic of sylvatic rabies in Finland--descriptive epidemiology and results of oral vaccination.

When rabies reappeared in Finland in April 1988, the country had been rabies free since 1959. Soon a picture of sylvatic rabies become evident, its main vector and victim being the raccoon dog (Nyctereutes procyonoides). Between 8 April 1988 and 16 February 1989, 66 virologically verified cases were recorded (48 raccoon dogs, 12 red foxes, 2 badgers, 2 cats, 1 dog and 1 dairy bull) in an area estimated at 1700 km2 in south-eastern Finland. The greatest distance between recorded cases was 67 km. A positive reaction with monoclonal antibody p-41 indicated that the virus was an arctic-type strain. A field trial on oral immunization of small predators was initiated in September 1988 using Tübingen fox baits according to the Bavarian model of bait distribution. Each bait contained 5*10(7) TCID50/ml modified live rabies virus (SAD-B19). The 6 months' surveillance indicate a seroconversion rate of 72% (N = 126) in the raccoon dog population, 67% (N = 56) in the red foxes and 13% (N = 16) in the badgers, when titers greater than or equal to 1.0 IU/ml are considered seropositive. In the whole follow-up period, no statistically significant difference could be detected between the raccoon dogs and red foxes in the rate of seroconversion or in the uptake of tetracycline from the baits. Notably high antibody levels were recorded in both raccoon dogs and red foxes within 4-5 months after vaccination. Of the seropositive animals, the proportion of animals with titers 3.0 IU/ml or greater was higher in raccoon dogs (73%) than in red foxes (51%) (x2 = 5.29, p less than 0.05). The trial shows that raccoon dogs can be immunized against rabies in the field with vaccine baits originally developed for controlling sylvatic rabies in foxes.     

Rabies in two privately owned domestic rabbits

Two privately owned domestic rabbits (Oryctolagus cuniculus) in Maryland were found to be infected with the raccoon variant of the rabies virus in 1998. Both rabbits had an acute onset of anorexia and paralysis or paresis of the left forelimb; 1 also developed head tremors and a head tilt. One of the rabbits became ill 25 days after being attacked by a raccoon (Procyon lotor) and was euthanatized 3 days after onset of illness. The other rabbit, which was housed in an outdoor hutch, died 4 days after onset of clinical signs; the source of infection in that rabbit remains unknown. Currently, there is not a rabies vaccine approved for use in rabbits; thus, the only way to prevent the infection in rabbits is to prevent exposure. Veterinarians in rabies-enzootic areas should be familiar with the clinical signs of rabies in rabbits and should caution rabbit owners about the need to protect their pets from contact with wildlife.     

The potential of oral vaccines for disease control in wildlife species

Numerous infectious diseases caused by bacteria or viruses persist in developed and developing countries due to ongoing transmission among wildlife reservoir species. Such diseases become the target of control and management programmes in cases where they represent a threat to public health (for example rabies, sylvatic plague, Lyme disease), or livestock production (for example bovine tuberculosis, brucellosis, pseudorabies), or where they threaten the survival of endangered animal populations. In the majority of cases, lethal control operations are neither economically feasible nor publicly supported as a practical means for disease management. Prophylactic vaccination has emerged over the last 15 years as an alternative control strategy for wildlife diseases, mainly driven by the success of widescale oral rabies vaccination programmes for meso-carnivores in North America and Northern Europe. Different methods have been trialled for the effective delivery of wildlife vaccines in the field, however oral vaccination remains the most widely used approach. Successful implementation of an oral wildlife vaccine is dependent on a combination of three components: an efficacious immunogen, a suitable delivery vehicle, and a species-specific bait. This review outlines the major wildlife disease problems for which oral vaccination is currently under consideration as a disease management tool, and also focuses on the technological challenges that face wildlife vaccine development. The major conclusion is that attenuated or recombinant live microbes represent the most widely-used vaccines that can be delivered by the oral route; this in turn places major emphasis on effective delivery systems (to maintain vaccine viability), and on selective baiting systems, as the keys to wildlife vaccine success. Oral vaccination is a valuable adjunct or alternative strategy to culling for the control of diseases which persist in wildlife reservoirs.     

Terrestrial rabies control in the European Union: Historical achievements and challenges ahead

Due to the implementation of oral rabies vaccination (ORV) programmes, the European Union (EU) is becoming progressively free of red fox (Vulpes vulpes)-mediated rabies. Over the past three decades, the incidence of rabies had decreased substantially and vast areas of Western and Central Europe have been freed from rabies using this method of controlling an infectious disease in wildlife. Since rabies control is a top priority in the EU, the disease is expected to be eliminated from the animal source in the near future. While responsible authorities may consider the mission of eliminating fox rabies from the EU almost accomplished, there are still issues to be dealt with and challenges to be met that have not yet been in the focus of attention, but could jeopardise the ultimate goal. Among them are increasing illegal movements of animals, maintaining funding support for vaccination campaigns, devising alternative vaccine strategies in neighbouring Eastern European countries and the expanding distribution range of several potential rabies reservoir species in Europe.     

Survey of wildlife rehabilitators regarding rabies vector species

OBJECTIVE: To evaluate the risks associated with wildlife rehabilitation and the reemergence of wildlife rabies in North Carolina through assessment of the status of knowledge and attitudes of licensed in-state wildlife rehabilitators about rabies and rabies vector species (RVS). DESIGN: Questionnaire survey. SAMPLE POPULATION: 672 North Carolina licensed wildlife rehabilitators registered in 1999. PROCEDURE: Wildlife rehabilitators were contacted by mail to determine their status of knowledge and attitudes regarding rabies and RVS. The questionnaire was designed to determine rehabilitators' recent experiences with RVS, attitudes toward regulations, and knowledge of rabies virus transmission. Results were analyzed by use of the chi2 test. RESULTS: Questionnaire responses were provided by 210 of the 672 (31.3%) wildlife rehabilitators. Among rehabilitators, there were some inconsistencies in their knowledge base regarding rabies (eg, 25% reported that they did not know at what age animals were capable of transmitting rabies virus). Most respondents were amenable to all proposed licensing prerequisites for handling RVS (ie, record keeping, additional training, and veterinarian support). Respondents reported > 580 calls annually about rehabilitating RVS, and 80% believed at least some of their peers were rehabilitating RVS illegally. CONCLUSIONS AND CLINICAL RELEVANCE: With the establishment of rabies as a disease that is endemic among wildlife species in North Carolina, educational efforts directed at wildlife rehabilitators (a subpopulation of residents potentially at high risk of rabies virus infection) would have direct and indirect public health benefits; similar efforts may be useful to public health communities elsewhere in the United States.     

Rabies surveillance in the United States during 2004

During 2004, 49 states and Puerto Rico reported 6,836 cases of rabies in nonhuman animals and 8 cases in human beings to the CDC, representing a 4.6% decrease from the 7,170 cases in nonhuman animals and 3 cases in human beings reported in 2003. Approximately 92% of the cases were in wildlife, and 8% were in domestic animals (compared with 91% and 9%, respectively, in 2003). Relative contributions by the major animal groups were as follows: 2,564 raccoons (37.5%), 1,856 skunks (27.1%), 1,361 bats (19.9%), 389 foxes (5.7%), 281 cats (4.1%), 115 cattle (1.7%), and 94 dogs (1.4%). Compared with the numbers of reported cases in 2003, cases in 2004 decreased among all groups, except bats, cattle, human beings, and "other domestics" (1 llama). Decreases in numbers of rabid raccoons during 2004 were reported by 12 of the 20 eastern states in which raccoon rabies was enzootic. In the East, Massachusetts reported the first cases of raccoon rabies detected beyond the Cape Cod oral rabies vaccine barrier. Along the western edge of the raccoon rabies epizootic (Ohio in the north and Tennessee in the south), cases of rabies were reported from unexpected new foci beyond oral rabies vaccine zones. On a national level, the number of rabies cases in skunks during 2004 decreased by 12.1% from the number reported in 2003. Once again, Texas reported the greatest number (n = 534) of rabid skunks and the greatest overall state total of rabies cases (913). Texas reported only 1 case of rabies in a dog that was infected with the dog/coyote rabies virus variant and only 22 cases associated with theTexas gray fox rabies virus variant (compared with 61 cases in 2003). The total number of cases of rabies reported nationally in foxes and raccoons declined 14.7% and 2.7%, respectively, during 2004. The 1,361 cases of rabies reported in bats during 2004 represented a 12.3% increase over the previous year's total of 1,212 cases for this group of mammals. Cases of rabies reported in cats, dogs, horses and mules, and sheep and goats decreased 12.5%, 19.7%, 31.8%, and 16.7%, respectively, whereas cases reported in cattle increased 174%. In Puerto Rico, reported cases of rabies in mongooses decreased 4.1% and rabies in dogs (9 cases) remained unchanged from those reported in 2003. Among the 8 cases of rabies in human beings, 1 person from Oklahoma and 3 from Texas died following receipt of infected organs and tissues from an Arkansas donor. In California, a person originally from El Salvador and, in Florida, a person originally from Haiti both died of canine rabies infections acquired outside the United States. In Wisconsin, a teenager contracted rabies from a bat bite and became the first known person to survive rabies despite not having received rabies vaccine prior to symptom onset.     

A Conceptual Model for the Impact of Climate Change on Fox Rabies in Alaska, 1980–2010

The direct and interactive effects of climate change on host species and infectious disease dynamics are likely to initially manifest\ at latitudinal extremes. As such, Alaska represents a region in the United States for introspection on climate change and disease. Rabies is enzootic among arctic foxes (Vulpes lagopus) throughout the northern polar region. In Alaska, arctic and red foxes (Vulpes vulpes) are reservoirs for rabies, with most domestic animal and wildlife cases reported from northern and western coastal Alaska. Based on passive surveillance, a pronounced seasonal trend in rabid foxes occurs in Alaska, with a peak in winter and spring. This study describes climatic factors that may be associated with reported cyclic rabies occurrence. Based upon probabilistic modelling, a stronger seasonal effect in reported fox rabies cases appears at higher latitudes in Alaska, and rabies in arctic foxes appear disproportionately affected by climatic factors in comparison with red foxes. As temperatures continue a warming trend, a decrease in reported rabid arctic foxes may be expected. The overall epidemiology of rabies in Alaska is likely to shift to increased viral transmission among red foxes as the primary reservoir in the region. Information on fox and lemming demographics, in addition to enhanced rabies surveillance among foxes at finer geographic scales, will be critical to develop more comprehensive models for rabies virus transmission in the region.     

Baylisascariosis (Baylisascaris procyonis)--a rare parasitic zoonosis in Europe

Raccoons (Procyon lotor) were imported from North America into Germany many decades ago, and nowadays they are part of the home wildlife fauna. Unfortunately, the raccoon roundworm, Baylisascaris procyonis, was also imported. This nematode species is well known as an important agent of larva migrans in more than 100 animal species including man in North America, causing a fatal neurological or severe ocular disease. There are also several respective reports from Germany. A review about the biology of B. procyonis as well as the occurrence, epidemiology, pathology, clinical symptoms, zoonotic aspects of the baylisascariosis and possible preventive measurements is given.     

Rabies surveillance in the United States during 2007

SUMMARY: During 2007, 49 states and Puerto Rico reported 7,258 cases of rabies in animals and 1 case in a human to the CDC, representing a 4.6% increase from the 6,940 cases in animals and 3 cases in humans reported in 2006. Approximately 93% of the cases were in wildlife, and 7% were in domestic animals. Relative contributions by the major animal groups were as follows: 2,659 raccoons (36.6%), 1,973 bats (27.2%), 1,478 skunks (20.4%), 489 foxes (6.7%), 274 cats (3.8%), 93 dogs (1.3%), and 57 cattle (0.8%). Compared with numbers of reported cases in 2006, cases in 2007 increased among dogs, bats, foxes, and skunks while decreases were reported among cattle, cats, and skunks. Increases in numbers of rabid raccoons during 2007 were reported by 11 of the 20 eastern states where raccoon rabies was enzootic, and reported cases increased by 1.7% overall, compared with 2006. On a national level, the number of rabies cases in skunks during 2007 decreased by 1.1% from the number reported in 2006. Texas reported the greatest number (n = 362) of rabid skunks and the greatest overall state total of animal rabies cases (969). No cases of rabies associated with the dog/coyote rabies virus variant were reported. The United States remains free of dog-to-dog transmission of canine rabies virus variants. The total number of cases of rabies reported nationally in foxes increased 14.5%, compared with 2006. Increases in the number of reported rabid foxes were attributable to greater numbers of foxes reported with the Arctic fox rabies virus variant in Alaska, the Texas gray fox rabies virus variant in Texas, and the raccoon rabies virus variant in Virginia. The 1,973 cases of rabies reported in bats represented a 16.6% increase over numbers reported in 2006. Cases of rabies in dogs and in sheep and goats increased 17.7% and 18.2%, respectively, whereas cases reported in cattle, cats, and horses and mules decreased 30.5%, 13.8%, and 20.8%, respectively. In Puerto Rico, reported cases of rabies in mongooses decreased 51.5%, and rabies in domestic animals, presumably attributable to spillover infection from mongooses, increased 25%. One human rabies case was reported from Minnesota during 2007. Although typing of the rabies virus variant in this case was not possible, an investigation of this case indicated a bat as the most likely source of exposure.