Wild waterbirds are reservoir hosts for avian influenza viruses (AIV), which can cause devastating outbreaks in multiple species, making them a focus for surveillance efforts. Traditional AIV surveillance involves direct sampling of live or dead birds, but environmental substrates present an alternative sample for surveillance. Environmental sampling analyzes AIV excreted by waterbirds into the environment and complements direct bird sampling by minimizing financial, logistic, permitting, and spatial-temporal constraints associated with traditional surveillance. Our objectives were to synthesize the literature on environmental AIV surveillance, to compare and contrast the different sample types, and to identify key themes and recommendations to aid in the implementation of AIV surveillance using environmental samples. The four main environmental substrates for AIV surveillance are feces, feathers, water, and sediment or soil. Feces were the most common environmental substrate collected. The laboratory analysis of water and sediment provided challenges, such as low AIV concentration, heterogenous AIV distribution, or presence of PCR inhibitors. There are a number of abiotic and biotic environmental factors, including temperature, pH, salinity, or presence of filter feeders, that can influence the presence and persistence of AIV in environmental substrates; however, the nature of this influence is poorly understood in field settings, and field data from southern, coastal, and tropical ecosystems are underrepresented. Similarly, there are few studies comparing the performance of environmental samples to each other and to samples collected in wild waterbirds, and environmental surveillance workflows have yet to be validated or optimized. Environmental samples, particularly when used in combination with new technology such as environmental DNA and next generation sequencing, provided information on trends in AIV detection rates and circulating subtypes that complemented traditional, direct waterbird sampling. The use of environmental samples for AIV surveillance also shows significant promise for programs whose goal is early warning of high-risk subtypes.

Bacterial kidney disease, caused by Renibacterium salmoninarum, threatens salmonids worldwide. Following devastating mortality episodes in Oncorhynchus spp. in Lake Michigan, US, in the 1980s and infection rates >90%, pathogen prevalence has steadily declined to <5% over three decades in the three state-managed stocks. In this study, we sought to determine if the declining infection rates were associated with heightened circulating antibodies in state-managed Oncorhynchus spp. residing in the Lake Michigan watershed. A single-dilution, indirect enzyme-linked immunosorbent assay (ELISA) was modified to detect circulating antibodies against R. salmoninarum. Baseline values were delineated from naive chinook salmon (Oncorhynchus tshawytscha) and rainbow trout (Oncorhynchus mykiss). The assay was first used to assess primary antibody production over a 4-wk period in chinook salmon experimentally infected with R. salmoninarum. Mean antibody response was detected as early as 2 wk postinfection and continued to increase to the end of the observation period. The modified ELISA was then used to detect antibodies in serum samples collected from feral adult chinook salmon, coho salmon (Oncorhynchus kisutch), and steelhead trout (O. mykiss) returning to spawn at Lake Michigan weirs in 2009 and 2013. Results demonstrated that about 80% of feral Oncorhynchus spp. had measurable titers of circulating antibodies to R. salmoninarum. The relative ease and reasonable costs of this modified ELISA makes it a valuable serosurveillance tool for assessing the humoral immune status of feral salmonid populations.

Leptospirosis is reported infrequently in wild and domestic felids. We estimated the prevalence of Leptospira spp. infection and exposure using real-time PCR and serology, respectively, in 136 mountain lions (Puma concolor) and 39 bobcats (Lynx rufus) that died or were euthanized between 2009 and 2017 from several regions of California, US. Felids were classified as Leptospira-positive if they were test-positive using real-time PCR targeting the LipL32 gene of pathogenic Leptospira spp. or microscopic agglutination test for six serovars of Leptospira spp. The overall Leptospira spp. prevalence was 46% (63/136) for mountain lions and 28% (11/39) for bobcats. The most common serovar detected in both felid species was Leptospira interrogans serovar Pomona. Age class and geographic location were significantly associated with Leptospira spp. in mountain lions, but not in bobcats. Interstitial nephritis, predominately lymphocytic, was diagnosed in 39% (41/106) of mountain lions and 16% (4/25) of bobcats evaluated histologically and was significantly associated with being Leptospira spp.-positive in both species. Our findings suggest that Leptospira spp. infection is common and widespread in California's wild felids and may have clinical impacts on renal and overall health of individuals. Key words: Bobcat, Leptospira spp., leptospirosis, Lynx rufus, mountain lion, nephritis, pathology, Puma concolor.

Moose (Alces alces americanus) populations in many areas along the southern extent of the North American moose range, including Minnesota, have experienced decline. Ascertaining neonate health and cause-specific mortality is critical where calf survival is low and understanding underlying causes of population dynamics is important. To investigate moose neonate health and causes of mortality, we studied 43 calves shortly after parturition during 2013–15 and 2018. The observed natural calf mortality rate was 84% by the following January of each calving season. Most natural calf mortalities were caused by black bear (Ursus americanus) or wolf (Canis lupus) predation or associated injuries (71%) but also included stillbirth (16%), orphaning (7%), generalized bacterial infection (3%), and hunter harvest (3%). Neonate health was evaluated in 27 calves by hematology, serum biochemistry profile, and maternally derived immunoglobulin. General health parameters were mostly within an expected range for normal health and adequate maternal immunoglobulin transfer. Importantly, these data contribute to a growing body of literature on moose neonate health and is the first report, to our knowledge, of maternally derived immunity in moose neonates.

Eastern populations of Ruffed Grouse (Bonasa umbellus) have been in a decades-long decline across the mid-Atlantic and southern Appalachian Mountains of the US. West Nile virus (WNV), which first arrived in the US in 1999, is suspected to have contributed to these declines based on decreased population indices since the arrival of WNV in Pennsylvania as well as on high, experimentally induced WNV-associated morbidity rates. A 3-yr statewide survey was conducted across Pennsylvania to measure flavivirus (i.e., WNV) seroprevalence among hunter-harvested grouse. The overall seroprevalence from 2015–17 was 14.4% (81/563); annual seroprevalence ranged from 2.8% (4/145) in the 2017 hunt year to 22.6% (52/230) in 2016–17. We analyzed the effects of numerous variables (i.e., Ruffed Grouse age and sex, hunt year, WNV vector index [VI], and region of Pennsylvania) on WNV serostatus by logistic regression. While there was no significant difference in WNV seroprevalence between sex and age group, there was significant variation in seroprevalence between geographic regions of Pennsylvania and across hunt years. Additionally, there was a negative correlation between WNV seroprevalence and VI. Low seroprevalence rates among Ruffed Grouse corresponded to years with a high VI, supporting experimental findings that Ruffed Grouse may be highly susceptible to WNV-associated disease. Additional strategic research efforts are essential to more effectively measure the effects of WNV on Ruffed Grouse and other vulnerable avian species.

The warthog (Phacochoerus africanus) can be used as a model for investigating disease transmission at the human, wildlife, and livestock interface. An omnivore and scavenger, a warthog moves freely between natural ecotypes, farmland, and human communities and is susceptible to diseases of zoonotic, agricultural, and conservation concern. A retrospective study using 100 individual serum samples collected from May 1999 to August 2016 was performed to determine antibody prevalence to seven pathogens in warthogs from five locations in northeastern South Africa. Higher prevalence of antibodies to African swine fever virus and Mycobacterium bovis were detected in warthogs from the Greater Kruger National Park ecosystem in comparison to lower prevalence of antibodies to M. bovis and no antibodies to African swine fever virus in warthogs from uMhkuze Game Reserve. Low prevalence of antibodies to foot-and-mouth disease virus, Rift Valley fever virus, and influenza A virus was detected in all locations, and no antibodies against Brucella and Leptospira spp. were detected. No statistically significant difference in antibody prevalence was found between sexes for any disease. At the univariate analysis, M. bovis seropositivity was significantly different among age categories, with 49% (35/71) of adults found positive versus 29% (4/14) of juveniles and 9% (1/11) of sub-adults (Fisher's exact test, P=0.020), and between the sampling locations (Fisher's exact test, P=0.001). The multivariate model results indicated that juvenile warthogs had lower odds of testing positive to M. bovis antibodies than adults (juveniles' odds ratio [OR]=0.17, 95% confidence interval [CI]: 0.02–1.0), although this result was not statistically significant at the 5% level (P=0.052). For warthogs sampled at Satara Buffalo Camp, the odds (OR=0.22, 95% CI: 0.035–0.96) of being M. bovis antibody positive were significantly lower (P=0.043) than for warthogs sampled at Skukuza. Of particular interest in this study was the detection of warthogs seropositive for influenza A virus.

Dictyocaulus spp. infections are common in North American cervids, with Dictyocaulus viviparus described as most common. A Rocky Mountain elk (Cervus canadensis nelsoni) was found dead in Wyoming, US with significant bronchitis and pneumonia. In the bronchi and trachea, numerous large nematodes were found and grossly identified as Dictyocaulus spp. lungworms. Macroscopic alterations, such as distended interlobular septa and edema with foam and mucus observed on cut surface and in trachea and bronchi, were consistent with those commonly described in D. viviparus infections. Female lungworms were identified to Dictyocaulus spp. level via morphologic examination and molecular analyses based on mitochondrial cyclooxygenase 1 and 18S ribosomal RNA genes. A phylogenetic analysis was conducted employing the maximum likelihood method. Based on both morphologic and genetic assays, the isolated lungworms were most likely a strain of Dictyocaulus cervi. Within the female adult worms, free first stage larvae were observed besides worm eggs, which had not been described for Dictyocaulus spp. Phylogenetic analysis revealed that our parasites clustered closely with D. cervi, forming a subclade with that species within a larger clade that includes Dictyocaulus eckerti. While the elk tested positive for chronic wasting disease, it is assumed that significant pathology in the present case was caused directly by infection with the D. cervi-like lungworm, not previously described in North America.

Epizootic hemorrhagic disease (EHD) is the most significant source of viral disease–related mortality in white-tailed deer (Odocoileus virginianus) in the US. Deer mortality from EHD has increased in the state of Michigan, US, since 2006, with the largest outbreak occurring in 2012. The 2012 outbreak provided an opportunity to evaluate how this disease affected EHD-related mortality in deer populations at a spatial scale typical of that expected for the greatest disease risk. Our objectives were to quantify the population impacts and spatial extent of EHD associated with areas of disease risk for deer populations and to determine how populations recovered over time following localized EHD impacts. We estimated the annual local abundance of deer for 5 yr immediately following a recent EHD outbreak. Because proximity to wetlands may affect EHD occurrence, we surveyed deer at varying distances (about 1 km and 5 km) from a riparian corridor to determine spatial variation in population impacts. Further, we assessed differences in deer abundance for sites affected and unaffected by EHD. Abundance estimates were lower along transects near the riparian corridor only in the affected area, reflecting EHD mortality associated with wetlands. The only change in abundance over time was a significant increase in the riparian strata in the EHD-affected site.

Baylisascaris procyonis is a zoonotic parasite that can cause serious health issues in their intermediate hosts. Eggs of the parasite are shed in the feces of raccoons (Procyon lotor), the definitive host, and can remain viable in the environment for years. Temperatures at 49 C are the LD50 for B. procyonis eggs. Our objective was to determine the effect of prescribed fire as a lethal control technique for B. procyonis eggs. Aliquots of 1,000 viable B. procyonis eggs were placed on the soil surface and at a depth of 2 cm within 10×10 m grass plots consisting of approximately 2,000 kg/ha and 4,000 kg/ha fuel loads. In addition, aliquots of 1,000 viable B. procyonis eggs were placed at 0, 0.7, 1.2, and 1.8 m from the fire's edge and within a 1 m² circle of bare ground on the leading edge, center of circle, and trailing edge of the fire of similar plots. Prescribed fire killed B. procyonis eggs on the soil surface up to 0.7 m from the fire's edge at fuel loads of 4,000 kg/ha but was ineffective at depths of 2 cm. Fuel loads of 2,000 kg/ha killed only 50% of B. procyonis eggs on the soil surface at the fire's edge but was not effective killing eggs at greater distances or at soil depths. Prescribed fire can be used to reduce the quantity of B. procyonis eggs on the soil surface within an environment but will not be effective in eradicating the parasite eggs.

Canine distemper virus (CDV) has a broad mammalian host range. In Ontario, Canada, CDV is frequently encountered in wild carnivores and is the most common infectious cause of death for raccoons (Procyon lotor). The isolation of wild-type CDV strains genetically distinct from vaccine strains in North America has renewed interest in the epidemiological patterns of this virus. However, wildlife surveillance is challenging and often utilizes a combination of surveillance methods with aggregation of data from multiple sources. Our objective was to compare raccoon CDV data generated through two separate surveillance components operated by the Ontario-Nunavut node of the Canadian Wildlife Health Cooperative. The raw data generated by each component in addition to the results of multilevel logistic regression and spatial scan statistics, were compared between the datasets. A total of 498 raccoons obtained via passive surveillance between 2007 and 2017 and 887 raccoons obtained via enhanced-passive surveillance between 2014 and 2017, were tested for CDV. The number and geographic distribution of reports, proportion of yearly reports classified as CDV-positive, and characteristics of CDV-positive raccoons differed between passive and enhanced-passive surveillance components. Geographical data demonstrated that CDV infection was present throughout southern Ontario. The geographic area of both surveillance components combined was more representative than either passive or enhanced-passive surveillance in isolation; but was restricted compared to the overall distribution of raccoons in Ontario. Regression analyses produced statistically significant associations between the presence of CDV and host and environmental variables that were at times discordant between the two datasets. Studying the properties of these datasets will inform future passive wildlife surveillance strategies and highlights the impact that a surveillance strategy can have on the results of epidemiological analyses.

Herbivores can be accidental hosts for the zoonotic nematode parasites Trichinella spp., which are endemic at high prevalence in wildlife in northeastern Europe. Using direct and indirect detection methods for Trichinella spp., we investigated samples from 463 wild moose (Alces alces) harvested by hunters in Estonia in 2015. A total of 460 moose were tested directly by artificial digestion of diaphragm muscle, 463 moose were tested indirectly by enzyme-linked immunosorbent assay (ELISA), and 34 moose also by western blot. Positive-control reference sera were from other host species. Nematode larvae were found in six muscle samples; five of which were pooled samples. None of the larvae were identified as Trichinella spp., based on their morphology and molecular analyses. Twelve moose (2.6%) were positive by ELISA, but none were positive by the western blot test. Trichinella spp. infection was not detected, but ELISA results may suggest Trichinella spp. exposure in a small proportion of moose in Estonia.

Invasive rodents on islands have adverse effects on native birds in island ecosystems, and rats are the most common culprits. Recently, house mice (Mus musculus) in the South Atlantic were found preying on three species of albatross chicks. Here, we show that house mice can also prey on nesting adult Laysan Albatross (Phoebastria immutabilis) on Midway Atoll National Wildlife Refuge (US). In contrast to mouse attacks on albatross in the South Atlantic, where mice targeted the rump and crown of chicks, on Midway, mice targeted nesting adults mainly on the back. For both regions, the outcome was similar with reduced nesting success. In the case of Midway, reduced nesting success was due to nest abandonment or mortality of one or both parents because of secondary bacterial infections. Mouse-induced mortality of adult albatross has the potential to have a more potent demographic effect because of their much higher natural survivorship once they reach adulthood.

Approximately 1.86 million baits containing a vaccinia-rabies glycoprotein recombinant vaccine were distributed with helicopters, vehicles, and bait stations during 2006–10. A bait density of 250 baits/km² effectively controlled rabies cases in enzootic and preepizootic areas. However, a cluster of 11 rabid raccoons at the eastern edge of infection resulted in the initiation of semiannual, high-density (500 baits/km²) vaccination campaigns in approximately 20% of the oral rabies vaccination zone during July and September (2007–09). Bait success (i.e., chewed sachets or removed baits) at bait stations was negatively associated with station distances from water. Conversely, bait success improved with increasing distances from roads. Bait stations deployed significantly more baits in developed open space when compared to low- and medium- to high-intensity developed areas. However, a difference was not detected between developed open space and forest habitats. Rabies was confined to 86 raccoons within 317 km² (10%) of a 3,133 km² suburban landscape, with a disproportionate number of rabid raccoons (n=74) in developed areas, when compared to 10 cases in forest–wetland habitats. Two rabid raccoons did not fall within either general land-use classification. Rabies advanced 15.1 km eastward at a rate of 6.4 km/yr during a 28-mo interval (2004–06).

Vaccine-laden baits were distributed to interrupt and halt raccoon (Procyon lotor) rabies transmission in suburban Nassau and Suffolk counties on Long Island, New York, US. Fishmeal polymer baits containing the RABORAL V-RG^® vaccine were deployed with helicopters, bait stations, and vehicles at a target density of 250 baits/km² during annual September campaigns (2006–10). Semiannual campaigns (500 baits/km²) were also initiated in a portion of the treatment zone (2007–09) in response to a persistent focus of rabid raccoons. The last enzootic case was reported in January 2009. The final vaccination campaign was completed in 2010. The raccoon variant of rabies virus is no longer circulating in Nassau or Suffolk counties. Significantly greater probabilities of raccoon seroconversion were observed in helicopter-deployed bait zones. The lowest probabilities of seroconversion were identified in vehicle and bait station-deployment bait zones, with a marginal advantage associated with bait-station deployment. Seroconversion was negatively associated with developed, medium-intensity areas and increasing human population density. Significantly higher rabies virus neutralizing antibody endpoint titrations were detected in helicopter and bait station-deployment zones.

Leptospira interrogans is one of the most important zoonotic pathogens globally. In urban settings, Norway rats (Rattus norvegicus) are important reservoirs of L. interrogans, but it is unclear how this bacterium is transmitted among rats. Both environmental features and rat population density may determine the prevalence of this pathogen in rat populations as well as the spillover risk to people. While these factors could play an important role in transmission between rats, it is unknown whether such factors influence prevalence among rats at a fine scale. Our objective was to determine if carriage of L. interrogans by rats could be explained by variation in the environment or in rat population density. Rats were live-trapped in a single neighborhood of Vancouver, Canada during two study periods (2011–12; 2016–17) and were tested for L. interrogans. The physical environment of each city block was recorded using a comprehensive, in-person environmental survey. Using generalized linear mixed modelling, we found no evidence of an association between carriage of L. interrogans and environmental features or rat population density, suggesting that these were not the primary drivers of its distribution among rats within this neighborhood. Understanding factors that promote L. interrogans transmission can be used to inform management approaches to minimize public health risks.

Anticoagulant rodenticides (AR), principally difethialone, brodifacoum, and bromadiolone, were detected in the livers of 89% of 72 Red-tailed Hawks (Buteo jamaicensis) from New York City, New York, US examined for cause of death over a 7-yr period (January 2012–December 2018). Fatal hemorrhage likely attributable to AR exposure was diagnosed in 41% (30/74) of cases, and 46% (18/39) of the cases analyzed with no gross evidence of AR-mediated hemorrhage had liver concentrations of AR that overlapped those with an AR-poisoning diagnosis. Although urban areas like New York City can support surprisingly dense populations of Red-tailed Hawks, the threat posed by extensive use of AR can be large.

Serum samples obtained from 474 wild boars (Sus scrofa) were collected from June 2017 to September 2018 from various areas of northern and southern Poland. Serum samples were examined by enzyme-linked immunosorbent assay. However, West Nile virus (WNV) antibodies were not detected. Previous studies on WNV in Poland have focused on experimental evidence and the presence of WNV antibodies in wild birds, horses, and humans, indicating a need for more surveys of domestic and wild mammals in Poland.

The emergence and dissemination of resistance to clinically important antimicrobials in wild animals is of great concern. The aim of our study was to reveal the prevalence and intraspecies dissemination of quinolone-resistant Escherichia coli (QREC) in sika deer (Cervus nippon) in Nara Park, a famous tourist spot in Japan. Fecal samples were collected from 59 wild deer in Nara Park between July and October 2018. We isolated QREC using deoxycholate-hydrogen sulfide-lactose agar containing nalidixic acid and subjected it to antimicrobial susceptibility testing. The mutations in the quinolone resistance-determining region (QRDR) of the gyrA and parC genes of the isolates were analyzed and fragment patterns of genomic DNA were compared by pulsed-field gel electrophoresis (PFGE). A total of 105 QREC isolates were obtained from 41 deer (70%). All isolates had mutations within the QRDR. Other than quinolone resistance, QREC isolates also showed resistance to various other antimicrobial agents. The QREC isolates were classified into 15 PFGE clusters, of which seven were observed in multiple deer. Our results suggest clonal transmission of QREC in a high-density deer population. Spread of QREC in deer inhabiting a tourist location could have potential impact on public health.

Hematology and serum biochemistry reference intervals were estimated for the Iberian hare (Lepus granatensis). Most parameters differed significantly between hunted and livetrapped Iberian hares. Significant differences were found for sex (red blood cell count, mean corpuscular volume, total protein, albumin, uric acid, triglycerides, cholesterol, chloride) and age classes (red blood cell count, hematocrit, mean corpuscular hemoglobin, glucose, calcium, and sodium). Sex- and age-specific reference intervals were estimated for these parameters. Red blood cell count, hemoglobin concentration, mean corpuscular hemoglobin, urea, and potassium show seasonal variations, with the lowest values in summer and the highest in winter. Creatinine, calcium, sodium, and phosphorus achieve their highest values in summer and stable baseline values throughout the rest of the year. These reference intervals can be used as baseline to monitor health, physiology, ecology, and nutrition of Iberian hare populations.

Hunting activities are a potential risk factor for human infection with Leptospira spp. and, although wild boar seroprevalence has been studied, there are no concurrent serosurveys of wild boars (Sus scrofa), hunting dogs (Canis lupus familiaris), and hunters. The aim of our study was to assess the seroprevalence of Leptospira spp. antibodies in free-ranging wild boars, hunting dogs, and hunters, and risk factors associated with exposure in southern and central-western Brazil. Leptospira spp. antibodies were serologically detected using the microscopic agglutination test, with a total 30 serovars. Overall, 12.2% (9/74) of wild boars and 10.6% (16/170) of hunting dogs were seropositive for at least one serovar and all hunters 0.0% (0/49) were seronegative for Leptospira spp. Seropositivity was statistically higher in 42.1% (8/19) wild boars from natural areas when compared to 2.4% (1/41) from anthropized areas (P<0.001), with prevalence ratio of 17.14 (95% confidence interval: 2.29–128.36). Despite the limited sample size, our findings showed that hunters may be less exposed to Leptospira spp. than are wild boars, particularly in natural areas where Leptospira spp. may be maintained by wild reservoirs. In addition to acting as sentinels, hunting dogs may play a role in disease transmission of sylvatic leptospiral serovars.

We investigated whether naturally acquired maternal antibodies to epizootic hemorrhagic disease virus serotype 2 (EHDV-2) would protect white-tailed deer (Odocoileus virginianus) fawns against infection and clinical disease following an EHDV-2 challenge. We compared viremia and clinical response in 27–47-d-old, experimentally infected fawns with and without maternally derived antibodies to EHDV-2. Mild to moderate clinical signs were observed in four seronegative (maternal antibody-negative) fawns, which were viremic from 3 to 14 d postinoculation. Individual peak blood virus titers for seronegative fawns ranged from 10^4.3 to 10^6.3 median tissue culture infective doses (TCID₅₀)/mL. In contrast, clinical signs were not observed in seropositive (maternal antibody-positive) fawns and a transient low-level viremia (≤10^2.4 TCID₅₀/mL) occurred in two of six fawns. Our results indicated that the presence of maternally derived EHDV-2 antibodies in fawns prevents or greatly reduces clinical disease and the level and duration of EHDV-2 viremia.

Chronic wasting disease (CWD) of white-tailed deer (Odocoileus virginianus) is a fatal neurologic disease that is spreading across North America. A common surveillance protocol for CWD currently involves screening with an enzyme-linked immunosorbent assay (ELISA) followed by confirmatory testing with immunohistochemistry (IHC). Medial retropharyngeal lymph nodes (MRPLN) are the tissue of choice to diagnose CWD in free-ranging white-tailed deer. We examined left and right MRPLN from 101 ELISA-positive deer harvested from 2015 to 2019 to determine the prevalence of cases in which prion protein was not detected by IHC as well as differences in IHC labeling between contralateral lymph nodes. Prion protein was not detected using IHC in either MRPLN in 5.9% (6/101) of cases. There was a significant but weak positive relationship between the number of IHC-positive follicles and ELISA optical density values (R²=0.08, P=0.039). Mean optical density values in IHC-positive MRPLN were higher than in IHC-negative MRPLN; however, this was not statistically significant (P=0.260). Failure to confirm ELISA diagnoses with IHC may have been because the methods tested different areas of MRPLN, or that there were differences in test sensitivity or antibody affinity. An additional 5.9% (6/101) of cases had one IHC-positive MRPLN, whereas the contralateral MRPLN was IHC negative. Therefore, testing a single MRPLN for CWD may lead to false-negative results, regardless of methodology, which highlights the importance of collecting and testing both MRPLN.

A mortality event of nine threatened smoky mice (Pseudomys fumeus) occurred in January 2020 at a captive breeding facility in southeastern Australia that was affected at the time by hazardous levels of bushfire smoke, despite being more than 20 km from the nearest fire. Pathologic and clinical observations indicated smoke inhalation was the cause of death. All animals had significant pulmonary lesions, notably pulmonary edema and congestion, and moderate amounts of dark brown to black pigmented intracellular and extracellular particles from <0.5–2.5 µm in diameter were observed in the central or hilar region of the lungs of four of six animals examined histologically. Deaths occurred between three and 30 d after exposure to smoke and, for seven animals in outdoor acclimatization enclosures, were associated with very high ambient temperature (>40 C). Similar mortalities did not occur in co-located parrots, suggesting differing species sensitivity to smoke inhalation. Our findings highlight the potential for smoke to be an underdiagnosed cause of mortality in free-ranging wildlife during bushfires and for bushfires to affect wildlife populations outside of burnt areas, including in unburnt refugia. Conservation interventions for wildlife after bushfires should consider and, where possible, mitigate the risk of animals dying due to increased respiratory demand following smoke inhalation injury.

We describe a case of systemic toxoplasmosis in a female adult narrow-ridged finless porpoise (Neophocaena asiaeorientalis) found in May 2018 inside a gillnet set in the Ariake Sound, southern Japan. The main lesions observed were lymphoplasmacytic and focally necrotizing encephalitis, necrotizing to granulomatous adrenalitis, myocarditis, and inflammation in the intestinal wall, associated with protozoal tissue cysts and tachyzoites. Additionally, the individual had a 5.6 mm (crown-rump length) early-stage embryo in the left uterine horn, which had multifocal necrotizing lesions with intralesional tissue cysts and tachyzoites in the parenchyma. Immunohistochemistry and PCR and sequencing of the internal transcribed spacer 1 region confirmed a Toxoplasma gondii infection. Further genotyping revealed an atypical type II genotype with a type I pattern for the Apico locus. Narrow-ridged finless porpoises are an endangered coastal species already facing various anthropogenic threats. Toxoplasmosis, especially with its ability to transmit to an early-stage embryo, should be considered an emerging threat to this vulnerable species.

Little information exists on the occurrence of Trichinella spp. in cougars (Puma concolor) throughout North and South America. However, species distribution models (SDM) can be used to predict suitable habitat for elusive species with limited occurrence data. In 2018, we used existing occurrence data to estimate the suitable habitat and ecological drivers of Trichinella species in cougars from the southwestern region of Colorado, US from winter months. Environmental layers were constructed and an SDM was then created for the southwestern region of Colorado. The final model (area under the curve=0.73) found areas of suitable habitat for Trichinella spp. to be associated with lower elevation, lower temperature, and higher proportions of evergreen needleleaf forests and grasslands. These results might indicate potential transmission hotspots for Trichinella spp. in the southwestern region of Colorado for where cougars are consuming infected hosts and where cougars can transmit to other hosts, including humans. However, due to limited occurrence data, more suitable habitat likely exists.

Carnivorous birds maintain parasites in the sylvatic cycle and have a role in their diffusion. The histopathology and ultrastructure of the intestine of 29 Hooded Crows (Corvus corone cornix) and 51 Eurasian Magpies (Pica pica), from the Province of Ferrara (Northern Italy), naturally infected with Sphaerirostris picae (Acanthocephala), were investigated. In both bird species, the prevalence of infection was around 10%, and the intensity of the infection in the Hooded Crows ranged from two to 12 acanthocephalans per host, whereas in the Eurasian Magpies it ranged from one to nine worms per bird. Previous records on the histopathology of acanthocephalans in birds do not provide information on the type of cells involved in the host's reaction. We aimed to gain information on the effects of acanthocephalans on the structural integrity of the birds' intestine and to describe the type of immune cells in the hosts against the parasite. Our results showed that S. picae disrupted the intestinal wall at the site of attachment by means of its neck and proboscis, and three main types of bird intestinal reactions were noticed. The most severe response of the hosts was against the proboscis because of the action of its hooks with recruitment of macrophages, giant cells, eosinophils, and heterophils. Sphaerirostris picae perforated the birds' entire intestinal wall, reaching the peritoneal visceral serosa, but it did not provoke a diffuse peritonitis.

We detail a novel presentation of tuberculosis associated with intestinal perforation in an endangered Australian sea lion (Neophoca cinerea) from South Australian waters and confirm the presence of this disease in the region of highest pup production. In February 2017, a 3-yr-old juvenile male died shortly after hauling out at the Kingscote beach on Kangaroo Island. On postmortem examination, we found a mid-jejunal intestinal perforation and partial obstruction (from a strangulating fibrous and granulomatous mesenteric mass), a marked multicentric abdominal fibrosing granulomatous lymphadenitis, and a large volume serosanguinous peritoneal effusion. Acid-fast bacteria were detected postmortem in cytologic preparations of the mesenteric lymph node and in histologic sections of jejunum and the encircling mass. Mycobacterial infection was confirmed by positive culture after 3 wk. Molecular typing using mycobacterial interspersed repetitive-unit–variable-number tandem-repeat typing with 12-locus analysis identified Mycobacterium pinnipedii. This case highlights the need for vigilance of zoonotic disease risk when handling pinnipeds, including in the absence of specific respiratory signs or grossly apparent pulmonary pathology. Increased serologic population surveillance is recommended to assess the species' risk from this and other endemic diseases, especially given its endangered status.

A wild muskox (Ovibos moschatus) with dermatitis typical of contagious ecthyma had secondary bacterial septicemia with Corynebacterium freneyi that included laminitis, hepatitis, and suppurative encephalitis. This case supports the association between orf virus infection and fatal secondary infections, which may have contributed to population declines on Victoria Island, Canada.

We necropsied an American black bear (Ursus americanus) from central Utah, US and found several liters of cloudy fluid and multiple white nodules in the peritoneal cavity. Histopathologic examination and staining with pancytokeratin and vimentin markers identified a peritoneal mesothelioma. Mesothelioma has not been reported previously in black bears.

Using PCR, we evaluated the presence of parvoviruses and Mycoplasma spp. in 123 American mink (Neovison vison), an introduced invasive carnivore in Chile. Our results showed all analyzed animals were negative for both pathogen groups. We cannot completely dismiss their presence, but if present, their prevalence should be lower than 2%.

The global SARS-CoV-2 pandemic and the role of bats in zoonotic spillover have renewed interest in the flight-as-fever hypothesis, which posits that high body temperatures experienced by bats during flight contribute to their high viral tolerance. We argue that flight-as-fever is unlikely to explain why bats harbor more viruses than other mammals on the basis of two lines of reasoning. First, flight temperatures reported in the literature overestimate true flight temperatures because of methodologic limitations. Second, body temperatures in bats are only high relative to humans, and not relative to many other mammals. We provide examples of mammals from diverse habitats to show that temperatures in excess of 40 C during activity are quite common in species with lower viral diversity than bats. We caution scientists against stating the flight-as-fever hypothesis as unquestioned truth, as has repeatedly occurred in the popular media in the wake of the SARS-CoV-2 pandemic.

We determined venous blood gas, acid-base, and biochemical parameters for thirteen free-ranging Indian flying foxes (Pteropus giganteus) in Myanmar, using a handheld i-STAT analyzer with CG8+ and CHEM8 cartridges. For field-based projects, portable blood analyzers enable identification and management of electrolyte and acid-base imbalances and collection of physiologic data, but present logistical challenges.

Ophidiomycosis (snake fungal disease) is an emerging threat to snake health worldwide. We report a case of disseminated ophidiomycosis in a California kingsnake (Lampropeltis californiae) from Plymouth, Amador County, California, US, which is the first report of the disease in this species and in a free-ranging snake in California.

Book reviews express the opinions of the individual authors regarding the value of the book's content for Journal of Wildlife Diseases readers. The reviews are subjective assessments and do not necessarily reflect the opinions of the editors, nor do they establish any official policy of the Wildlife Disease Association.