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The geographic range of the zoonotic raccoon roundworm (Baylisascaris procyonis) is expanding together with the range of its host, the raccoon (Procyon lotor). This creates a new public health risk in parts of Europe where this parasite was previously absent. In the Netherlands, a raccoon population is becoming established and incidental findings of B. procyonis have been reported. To assess the risk to public health, the prevalence of B. procyonis was determined in the province of Limburg, where currently the largest Dutch raccoon population is present, as well as in the adjoining region of southern Belgium. Furthermore, genetic methods were employed to assess invasion pathways of both the raccoon and B. procyonis to aid in the development of control measures. Macroscopic analysis of intestinal content and testing of faecal samples were performed to detect B. procyonis adults and eggs. The population genetics of both B. procyonis and its raccoon host were analysed using samples from central and northwestern Europe. B. procyonis was found in 14/23 (61%, 95% CI: 41%–78%) raccoons from Limburg, but was not detected in 50 Belgian raccoons. Genetic analyses showed that the majority of the Dutch raccoons and their roundworms were introduced through ex‐captive individuals. As long as free‐living raccoon populations originate from captivity, population control methods may be pursued. However, natural dispersal from the border regions will complicate prolonged population control. To reduce the public health risk posed by B. procyonis, public education to increase awareness and adapt behaviour towards raccoons is key. [ABSTRACT FROM AUTHOR]

The term retinopathy has been used to group several heterogeneous retinal abnormalities that are clearly acquired or are suspected/proposed to be inherited. Some share characteristic focal/multifocal hyperreflective tapetal lesions with a dark center, and areas of non‐tapetal depigmentation suggestive of patchy or diffuse outer retinal atrophy. Progression is variable, and some develop unilateral or bilateral fundus changes resembling the clearly inherited form of retinal degeneration referred to as PRA. In this Commentary and Review, we discuss the role of ocular larva migrans resulting in the entity we refer to as canine DUSN and suggest that it may be responsible for some of the retinal findings grouped under the retinopathy rubric that share this characteristic fundus lesion. [ABSTRACT FROM AUTHOR]

Baylisascaris procyonis is a common gastrointestinal parasite of raccoons (Procyon lotor) in their native range, and both have been introduced to Europe. Humans may ingest ascarid eggs shed via the racoons' faeces, and this could lead to severe infections affecting the central nervous system. Here, we report the first occurrence of B. procyonis in Austria. The parasite was detected in a two‐year‐old male raccoon that was road‐killed in November 2019 near Hittisau (Vorarlberg). Genetic profiling provided strong evidence that the raccoon (and its parasite) originated from the nearest German raccoon population. The first finding in Austria highlights the need for monitoring the parasite and information of the public and practitioners. [ABSTRACT FROM AUTHOR]

Baylisascaris procyonis, the raccoon roundworm, is a zoonotic ascarid of importance to human and animal health. Wildlife rehabilitators who care for raccoons may be at an increased risk for exposure to the parasite, especially if proper precautions are not taken. In a wider effort to evaluate awareness regarding B. procyonis in the wildlife rehabilitation community, an online survey (38-39 questions) including questions about B. procyonis knowledge and attitudes was developed and administered to wildlife rehabilitators. To assess precautions taken among raccoon rehabilitators, participants who rehabilitated raccoons (n = 447) answered additional questions about use of personal protective equipment (PPE) and infection control practices (ICPs). Reported use of gloves was variable, but hand hygiene was generally consistent. Masks and gowns were seldom used. Part-time or infrequent volunteers and rehabilitators located in the Central, Midwest and Southeast were significantly less likely to report consistent use of PPE. A total knowledge score from the survey was used to predict the likelihood of reporting the use of particular ICPs/PPE. Knowledge score had a highly significant but small effect on the likelihood of prophylactic use of anthelmintics, anthelmintics use for B. procyonis specifically, cleaning appropriately, and using species-dedicated housing. Risk factor analysis was performed on data from a prior serologic survey to evaluate factors associated with exposure to B. procyonis and inconsistent handwashing after contact with live raccoons and their faeces; practising rehabilitation in B. procyonis hyperendemic regions and practising rehabilitation in the western region were significant risk factors for being seropositive. These data further demonstrate that correct PPE/ICPs are critical in mitigating the risk of B. procyonis exposure among raccoon rehabilitators and among other captive species. [ABSTRACT FROM AUTHOR]

ABSTRACT Raccoon roundworm ( Baylisascaris procyonis), a common gastrointestinal parasite of the raccoon ( Procyon lotor), has been implicated in population declines of Allegheny woodrats ( Neotoma magister). Medicinal baiting is a viable tool in wildlife disease management although unique challenges exist for pathogenic systems in which the host can be immediately re-infected following treatment. Our goals were to evaluate the efficacy of using monthly distribution of anthelmintic baits to reduce the prevalence of B. procyonis infection in raccoons and to quantify patterns and rates of bait acceptance among populations repeatedly exposed to medicinal baits. We distributed baits monthly at a density of 200/km2 throughout 300-m buffer areas surrounding woodrat habitats in Indiana. We conducted raccoon latrine surveys annually to quantify the effect of treatment on roundworm prevalence and used remote cameras to identify the species contacting baits and determine the rate at which baits were removed. We observed declines in B. procyonis prevalence in response to treatment, but our ability to resolve statistical differences was limited by low pretreatment prevalence and high annual variability. Baits were removed rapidly from camera stations with 60% taken within 24 hours, 80% within 48 hours, and 90% within 72 hours. Virginia opossums ( Didelphis virginiana) removed 51% of baits whereas raccoons removed 44%. Identification of opossums as the predominant consumer of baits emphasizes the limitations imposed by non-target bait consumption for mitigation of B. procyonis and other wildlife diseases. The rapid removal of baits despite repeated bait exposure suggests that habituation did not result in bait aversion and fishmeal baits are a viable delivery system for mitigation of raccoon-borne diseases requiring repeated treatments. Similar treatment measures may facilitate conservation of Allegheny woodrats in habitats with high rates of B. procyonis-related mortality and could be used to reduce human exposure to this zoonotic parasite. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm ( Baylisascaris procyonis ) and inbreeding depression in the decline of the Allegheny woodrat ( Neotoma magister ), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución [ABSTRACT FROM AUTHOR]

Contemporary patterns of species decline frequently stem from multiple, synergistic pressures, which much like the genetic concept of lethal equivalents, must be interpreted in sum rather than as independent deleterious entities. For example, the recent, range-wide decline of the Allegheny woodrat ( Neotoma magister) is likely a result of numerous, minor, human-mediated stressors including habitat fragmentation and disruption of metapopulation dynamics, reduced hard mast availability associated with the functional extirpation of American chestnut ( Castanea dentata) and recent shifts in forest composition, and expansion of a human-adapted species, the raccoon ( Procyon lotor) and the parasites it carries ( Baylisascaris procyonis). To evaluate the assertion that range-wide woodrat declines have been caused by a concatenate of stressors, we used principal component ( PC) analysis to identify latent relationships among a suite of biological and ecological factors (reflecting those stressors listed above) and evaluated PC scores relative to the three conservation states of woodrat populations in Indiana (stable, diminished and extirpated). Populations of differing conservation states segregated along each of the three retained PCs, providing support for the assertion that a combination of stressors has contributed to the range-wide decline of woodrat metapopulations, although intriguingly, independent stressors appeared to cause the decline of individual populations. These results suggest specific, minimal site attributes must be met for each of the habitat attributes evaluated to support stable woodrat populations. Our findings further suggest that variation in relative pressures exerted by individual stressors across populations will require site-specific management actions if woodrat populations are to be recovered throughout their range. Our case study of Indiana woodrats exemplifies the first step in identifying site-specific causes for species' declines, necessary to guide subsequent management and recovery actions when a combination of interwoven factors likely are contributing to metapopulation degeneration. [ABSTRACT FROM AUTHOR]

The raccoon (Procyon lotor) is the definitive host of Baylisascaris procyonis, a large intestinal roundworm. The prevalence of infection among raccoon populations often is high, and in the midwestern United States B. procyonis is documented in 68-82% of raccoons. Because raccoon populations appear to be increasing in response to changes in human land use and because B. procyonis is considered an emerging zoonotic disease, it is important to determine reliable methods to monitor prevalence of infection among raccoons. We compared the relative sensitivity of 3 common methods used by wildlife biologists to determine prevalence in free-ranging raccoon populations. We determined prevalence of infection among midwestern raccoon populations from 456 raccoon fecal samples, 742 raccoon latrine samples, and 212 necropsies (gut analysis). We developed logistic regression models in order to predict the log likelihood of presence of B. procyonis in a given sample as a function of season, land use, and technique. Finally, we measured the sensitivity of fecal sampling by evaluating fecal samples taken from 72 necropsies for the presence of B. procyonis eggs. Necropsy analysis yielded the highest measure of prevalence (44%), followed by latrine samples (22.5%), and fecal samples (1 7.5%). Necropsy analysis explained the most variance in logistic models, suggesting that this is the most reliable method. However, this technique is labor-intensive and may not be the most efficient method for large-scale investigations of B. procyonis prevalence. Fecal analysis is a reliable method of determining prevalence among raccoons as we observed B. procyonis eggs in 66% of fecal samples taken from positive necropsies. Latrine sampling may be the most efficient method and perhaps the best estimator of zoonotic potential; however, wildlife managers should realize that this measure often is an underestimate of prevalence among raccoons and develop management plans accordingly. [ABSTRACT FROM AUTHOR]

Baylisascaris procyonis is a common parasitic nematode of the raccoon Procyon lotor. In intermediate or accidental hosts, including humans, B. procyonis can cause severe disease and mortality, and the parasite is increasingly viewed as an important wildlife conservation and public health concern. The prevalence of B. procyonis was assessed over a 4-year period in a population of raccoons in a forested region of lower New York. Prevalence ranged from 0% (undetected) to 21%, which was relatively low compared to values reported in other studies from the north-east. During year three of the study, a subset of the raccoon population was experimentally manipulated through altered resource distribution to enhance the contact of individuals. Within the manipulated subpopulation, prevalence of B. procyonis increased to 54% which was significantly greater than prevalence in the same subpopulation before perturbation or than prevalence among raccoons that were not subject to increased intraspecific contact. These observations suggest that altered resource distributions that directly influence raccoon behaviour may indirectly play a role in the ecology of B. procyonis. [ABSTRACT FROM AUTHOR]

Disease threats to endangered species are most commonly caused by exotic microparasites accidentally introduced into naïve populations by humans. The case of raccoon roundworm ( Baylisascaris procyonis ) and the Allegheny woodrat ( Neotoma magister ) is an exception to this general rule and, as such, may be useful in the identification of other macroparasite disease threats in the future. B. procyonis is an intestinal nematode of raccoons ( Procyon lotor ) that is highly pathogenic in intermediate hosts. It is hypothesized to have caused or contributed to the extirpation of the Allegheny woodrat from the northern parts of its range. I tested this hypothesis by reintroducing Allegheny woodrats into four historically occupied sites with varying natural levels of environmental contamination with B. procyonis eggs. Populations were monitored via radiotelemetry and trapping for 22 months. Woodrat populations in less contaminated release sites survived significantly longer than populations in highly contaminated sites, and there was a strong negative correlation between the number of raccoon latrines and woodrat population persistence. This case demonstrates several points relevant to the conservation of small populations: trophically transmitted parasites ( in which prey species serve as intermediate hosts to the parasites of their predators ) can be significant sources of mortality in intermediate host populations; native parasites should not be ignored as potential disease threats; and parasites of human-adapted wild animals are likely to threaten rare and endangered species. This case also illustrates a previously unrecognized route through which host density can be decoupled from disease dynamics and provides evidence of apparent competition in nature. [ABSTRACT FROM AUTHOR]

Physical changes in landscapes alter the abundance and distribution of species. Higher-order effects can occur when changes in ecological processes result in altered interspecific interactions and subsequent changes in a species’ abundance or persistence. Baylisascaris procyonis , a roundworm parasite of raccoons (Procyon lotor ), is pathogenic to numerous small vertebrates that serve as intermediate hosts, including white-footed mice (Peromyscus leucopus ). Raccoons have responded positively to agriculturally induced changes in landscapes, with potential consequences for intermediate hosts of B . procyonis . We examined white-footed mice from a homogeneous, predominantly forested landscape in south-central Indiana and a heterogeneous, predominantly agricultural landscape in northwestern Indiana for presence of larval B . procyonis . We compared prevalence of infection, intensity of infection, and average number of larvae per mouse between the landscapes, and among forest patches within the highly fragmented agricultural landscape. Prevalence, intensity of infection, and average number of larvae were significantly higher in the highly fragmented landscape. Within the agricultural landscape, regression models predicted probability of infection, intensity of infection, and average number of larvae per mouse per patch as functions of forest patch area and isolation. We conclude that positive responses of raccoons to agriculturally induced fragmentation of forests have resulted in increased encounter rates between white-footed mice and infective stages of B . procyonis between and within landscapes, resulting in increased transmission of the parasite to intermediate hosts. [ABSTRACT FROM AUTHOR]

The article focuses on Baylisascaris procyonis infections among raccoons that were importes to Norway as pets. It mentions that Baylisascaris procyonis is a nematode commonly found in wild raccoons in North America and produces large numbers of eggs that are resistant in the environment. It also discusses the risk factors of the infection on humans.