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We describe the use of conventional histology and immunohistochemistry against canine distemper virus (CDV) to examine the brains of domestic dogs with a confirmed diagnosis of CDV infection. Histologically, to identify the main typical lesions, we used conventional H&E stain; to evaluate the progressive demyelination, we used Luxol Fast Blue stain; and to identify the presence of viral particles in these affected regions, we used immunohistochemistry against CDV. We confirm that the histopathological analysis of brains of distemper-infected dogs is a powerful tool to evaluate the typical brain lesions and could be used as an interesting natural model to continue studying the pathogenesis of canine distemper in different species and/or other morbillivirus infections, like measles.

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Canine distemper virus (CDV) is a major threat to domestic dogs and wildlife worldwide. Molecular assays are the most sensitive and specific tests to diagnose the disease, however, the high CDV genetic variability may compromise laboratory diagnosis. Herein, we designed a high-coverage primer set for end-point (RT-PCR) and real-time (RT-qPCR) for CDV detection. Initially, we collected 194 complete/near-complete CDV genomes (GenBank) and analyzed them for highly conserved regions for primer design. We then assessed the in silico coverage, analytical sensitivity, specificity and diagnostic performance of RT-PCR/RT-qPCR reactions based on our primers. Furthermore, the coverage of our primers, as well as their analytical sensitivity and diagnostic performance, were compared to a commonly used primer set for CDV detection (named PP-I). Our forward (F) and reverse (R) primers fully matched 100 % (194/194) and 99 % (192/194) of the analyzed sequences, whereas the PP-I F and R primers fully matched 15 % (29/194) and 9 % (18/194) sequences, respectively. The detection limit of our RT-PCR and RT-qPCR was equivalent to that of PP-I primers (0.001 TCID50/mL). Out of 70 clinical samples tested, 38 were positive by our RT-PCR/RT-qPCR assays, whereas reactions with primers PP-I failed to detect 9/28 (32 %) positive samples selected for comparison purposes. In addition, our assays did not amplify other canine viruses associated with respiratory and neurological diseases: canine adenovirus 2, canine parainfluenza virus 2, canine herpesvirus 1 and rabies virus. Overall, we describe a high-coverage primer set for CDV detection, which represents an attractive tool for laboratory diagnosis of canine distemper.

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We evaluated the presence of antibodies against CaHV-1, CDV, and CPV-2 in serum samples from Brazilian wild carnivore species. Nine maned wolves and six crab-eating foxes were tested for CaHV-1 and CDV by virus neutralization test and CPV-2 by hemagglutination inhibition assay. Antibodies to CaHV-1, CDV, and CPV-2 were detected in serum samples of 1 (6.7%), 5 (33.3%), and 10 (66.7%) wild carnivores, respectively. Two maned wolves and one crab-eating fox were seropositive simultaneously for CDV and CPV-2. Antibodies against all viruses were detected in one crab-eating fox. This is the first report of CaHV-1 antibody detection in crab-eating foxes.

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Canine Distemper Virus (CDV) is a highly contagious virus that can cross mammalian species barriers and has widespread impacts on both domestic animals and wildlife populations. This study describes a recent outbreak of CDV in the Galapagos Islands in 2019. A total number of 125 dogs with clinical signs compatible with CDV were included in this study. Nasal swabs were taken and analyzed by RT-qPCR for the detection of CDV, resulting in a positivity rate of 74.4% (IC95%, 66-81%). Among the CDV positive dogs, 82.2% presented with respiratory signs, 48.8% neurological signs, and 28.9% gastrointestinal signs. CDV has been previously reported in the domestic canine population of the Galapagos Islands in 2001 and 2004. The current study shows how CDV is still a threat for the endemic and endangered Galapagos sea lion, despite recent policies for dog population control and CDV vaccination.

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Background: Canine distemper (CD) is a highly contagious viral disease caused by the canine distemper virus (CDV). In dogs, CDV infection is characterized by the presentation of systemic and/or neurological signs with viral persistence in some organs, including the central nervous system (CNS). Neurological damages resulting from CD are a defiance for veterinarians, due to occasioned clinical sequels that influence the patient quality of life. The treatment of sequelae should seek to promote the resolution or decrease of the deleterious effects that impede the patient independence. Thus, the present report aims to describe the action of antiparkinsonian medication (levodopa associated with carbidopa) administered to 3 dogs who presented neurological sequels resulting from the canine distemper. Cases: Dog 1. A 9-month-old male mixed breed; Dog 2. A 6-month-old male Shih Tzu. Dog 3. A 8-years-old bitch mixed breed. All animals were referred for neurological care because presented neurological damages after distemper involvement. Only the Dog 2 was vaccinated to CD. Dog 1 (mixed male) had severe myoclonus, lack of proprioception, decreased of muscle tonus and paralysis in both pelvic limbs, associated with a marked thoracolumbar kyphosis. Dog 2 (a puppy Shih Tzu male) presented myoclonus in PL, proprioceptive loss in thoracic and pelvic limbs, absence of withdrawal reflex in thoracic and pelvic limbs, decrease in muscle tonus in pelvic limb and increase in thoracic limb. Dog 3 (adult unneutered bitch) presented intense myoclonus, absence of proprioception, decrease in muscle tonus and paresis of pelvic limb. All patients were treated with antiparkinsonian medication (levodopa 250 mg associated with carbidopa 25 mg) with following dosages: Dog 1 received a commercially available tablet, orally once a day for 30 days, while Dogs 2 and 3 had doses calculated by extrapolation allometric. For the Dog 2 it was prescribed 0.25 mg of levodopa and 0.025 mg of carbidopa daily for 30 days. Dog 3 was treated with 1 mg of levodopa and 0.1 mg of carbidopa patient day for the same period. Thirty days after starting the treatment, the 3 patients were evaluated again, and showed improvement of the motor signs, and the treatment was maintained. At the next return (30 days): Dog 1 showed significant improvement, however, Dog 2 started to present epileptic seizures and nystagmus that were treated with levetiracetam, while the Dog 3 not returned. As Dog 1 had a better prognosis, treatment was maintained for 1 year, with the frequency being changed from 24 h x 24 h to 48 h x 48 h after 30 days and 72x72 h after another 30 days. Unfortunately, Dog 2 had a worsening of epileptic condition and died, while Dog 3 died by road-kill. Discussion: The cases reported are uncommon, because not exist information about the use of antiparksonian to treatment of neurological damages occasioned by canine distemper. Although there are emerging therapies, such as the use of mesenchymal stem cells, that can reduce these sequels, the access is still restricted to a few professionals. Thus, the use of medications for demyelinating diseases, as antiparkinsonian, may be an alternative. In fact, the three reported patients showed recovery of the motor and sensorial damages observed, which corroborates with the possibility of a new treatment using antiparkinsonian or other drugs to demyelinating diseases.

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Background: Acupuncture (AP) has been empirically used to relieve post-canine distemper virus (CDV) infection neurological signs in veterinary clinics. Objectives: This clinical study aimed to investigate the effects of AP combined with electroacupuncture (EA) on neurological function in dogs infected by CDV. Methods: Twenty-four CDV-infected dogs with neurological sequelae were recruited to receive weekly AP/EA sections for 24 weeks. Neurological improvements were assessed before each AP/EA session using a modified scoring system. Data were analyzed using the McNemar test, Friedman test, Fisher's exact test, and Kaplan-Meier curves (p < 0.05). Results: Neurological scores improved from seven to 24 weeks after AP/EA treatment compared with pretreatment scores (p < 0.001). Significant improvements were recorded over time for functional limb recovery, cranial nerve deficits, mental status (p = 0.025 - 0.014), and urinary function (p < 0.001). Myoclonus was improved and entirely reversed in 75% and 25% of the dogs, respectively. At the end of treatment, the proportion of dogs with normal proprioception, posture, hopping (p < 0.001), and superficial pain sensation responses (p = 0.004) was greater than pretreatment values. Conclusion: AP/EA therapy promoted significant neurological recovery in CDV-infected dogs and may be considered within the chronic phase of the disease to improve motor and sensory rehabilitation. However, these results are preliminary and must be confirmed by further investigations.

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Canine distemper is caused by canine distemper virus (CDV), a multisystemic infectious disease with a high morbidity and mortality rate in dogs. Nanotechnology represents a development opportunity for new molecules with antiviral effects that may become effective treatments in veterinary medicine. This study evaluated the efficacy and safety of silver nanoparticles (AgNPs) in 207 CDV, naturally infected, mixed-breed dogs exhibiting clinical signs of the non-neurological and neurological phases of the disease. Group 1a included 52 dogs (experimental group) diagnosed with non-neurologic distemper treated with 3% oral and nasal AgNPs in addition to supportive therapy. Group 1b included 46 dogs (control group) diagnosed with non-neurological distemper treated with supportive therapy only. Group 2a included 58 dogs with clinical signs of neurological distemper treated with 3% oral and nasal AgNPs in addition to supportive therapy. Group 2b included 51 dogs (control group) diagnosed with clinical signs of neurological distemper treated with supportive therapy only. Efficacy was measured by the difference in survival rates: in Group 1a, the survival rate was 44/52 (84.6%), versus 7/46 in Group 1b (15.2%), while both showed clinical signs of non-neurological distemper. The survival rate of dogs with clinical signs of neurological distemper in Group 2a (38/58; 65.6%) was significantly higher than those in Control Group 2b (0/51; 0%). No adverse reactions were detected in experimental groups treated with AgNPs. AgNPs significantly improved survival in dogs with clinical signs of neurological and non-neurological distemper. The use of AgNPs in the treatment of neurological distemper led to a drastic increase in the proportion of dogs recovered without sequels compared to dogs treated without AgNPs. The evidence demonstrates that AgNP therapy can be considered as a targeted treatment in dogs severely affected by canine distemper virus.

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This research aimed to investigate the occurrence of Chlamydia sp., Morbillivirus sp., Parvovirus sp., Leishmania sp. and Alphacoronavirus sp. in captive giant anteaters. Blood and fecal samples were taken from 16 animals in institutions from the states of Minas Gerais, Bahia and Distrito Federal, which had been in captivity for at least a year. A commercial rapid chromatographic immunoassay test was used for detecting coronavirus and parvovirus antigens, in addition to antibodies against leishmaniasis, all results being negative. In the case of the test for antibodies against distemper, four (4/16; 25%) anteaters had an average titration, two (2/16; 12.5%) a low titration and ten (10/16; 62.5%) were non-reactive. Using the DOT-ELISA (dot blotting) method for detection of immunoglobulin G, only one specimen obtained a 1 : 40 titration. For the polymerase chain reaction tests for Leishmania and Chlamydia, all samples were negative.

Esta pesquisa teve como objetivo investigar a ocorrência de Chlamydia sp., Morbillivirus sp., Parvovirus sp., Leishmania sp. e Alphacoronavirus sp. em tamanduás-bandeira cativos. Foram colhidas amostras de sangue e fezes de 16 animais em instituições dos estados de Minas Gerais, Bahia e Distrito Federal, que estavam em cativeiro há pelo menos um ano. Um teste comercial rápido de imunoensaio cromatográfico foi usado para detectar antígenos de coronavírus e parvovírus, além de anticorpos contra a leishmaniose, sendo todos os resultados negativos. No caso do teste para anticorpos contra a doença, quatro (4/16; 25%) tamanduás apresentaram titulação média, dois (2/16; 12,5%) uma titulação baixa e dez (10/16; 62,5%) não foram reativos. A partir do método DOT-ELISA (dot blotting) para detecção de imunoglobulina G, apenas um espécime obteve uma titulação de 1: 40. Para os testes de reação em cadeia da polimerase para Leishmania e Chlamydia, todas as amostras foram negativas.

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Canine distemper virus (CDV) is the etiological agent of a highly prevalent viral infectious disease of domestic and wild carnivores. This virus poses a conservation threat to endangered species worldwide due to its ability to jump between multiple species and produce a disease, which is most often fatal. Although CDV infection has been regularly diagnosed in Colombian wildlife, to date the molecular identity of circulating CDV lineages is currently unknown. Our aim was to evaluate the presence and phylogenetic characterization of CDV detected in samples from naturally infected Cerdocyon thous from Colombia. We sequenced for the first time the CDV infecting wildlife in Colombia and demonstrated the presence of South America/North America-4 Lineage with a higher relationship to sequences previously reported from domestic and wild fauna belonging to the United States of America. Our results are crucial for the understanding of the interspecies transmission of CDV in the domestic/wild interface and for the prevention and control of such an important multi-host pathogen.

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Canine distemper outbreak and coinfections in three giant anteaters and in a maned wolf has been described. Three giant anteaters developed respiratory and digestive clinical signs after the introduction of a maned wolf to a Wildlife Rehabilitation Center. The maned wolf and two anteaters died, and one anteater was euthanized. Post mortem and histopathologic exams revealed lesions associated with numerous intraepithelial inclusion bodies, mainly in the respiratory and digestive systems. Infection by distemper virus was confirmed in all animals by RT-PCR and gene sequencing, which revealed the Europe 1/ South America 1 strain, closely related to the strain from Canis familiaris. In addition to distemper, the animals had other comorbidities, such as toxoplasmosis and salmonellosis in the maned wolf and cutaneous candidiasis in an anteater. Considering the chronology of clinical manifestation in both species and the viral characterization, it is possible that the maned wolf was the source of infection to the anteaters. This study demonstrates the importance of implementing biosecurity measures in enclosures that house animals of different species, highlighting the importance of quarantine before introduction of new animals into the same environment.

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Marine mammals, regarded as sentinels of aquatic ecosystem health, are exposed to different pathogens and parasites under natural conditions. We surveyed live South American fur seals Arctocephalus australis and South American sea lions Otaria flavescens in Uruguay for Leptospira spp., canine distemper virus (CDV), Mycobacterium spp., Toxoplasma gondii, and Neospora caninum. Samples were collected from 2007 to 2013. The seroprevalence of Leptospira spp. was 37.6% positive, 50.9% negative, and 11.5% suspect for A. australis (n = 61) while for O. flavescens (n = 12) it was 67% positive, 25% negative, and 8% suspect. CDV RNA was not detected in any of the analyzed samples. Most animals tested seropositive to tuberculosis antigens by WiZo ELISA (A. australis: 29/30; O. flavescens: 20/20); reactivity varied with a novel ELISA test (antigens MPB70, MPB83, ESAT6 and MPB59). Seroprevalence against N. caninum and T. gondii was 6.7 and 13.3% positive for O. flavescens and 0 and 2.2% positive for A. australis respectively. To evaluate possible sources of infection for pinnipeds, wild rats Rattus rattus and semi-feral cats Felis catus were also tested for Leptospira spp. and T. gondii respectively. Water samples tested for Leptospira revealed saprofitic L. bioflexa. Pathogenic Leptospira were detected in the kidneys of 2 rats, and cats tested positive for T. gondii (100%). These results represent a substantial contribution to the study of the health status of wild pinnipeds in Uruguay.

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A cinomose é uma doença viral multissistêmica causada por um Morbillivirus. No Brasil, existem seis espécies de canídeos silvestres vulneráveis a essa enfermidade. Dessa forma, este trabalho tem como objetivo apresentar uma revisão sobre a situação da cinomose em canídeos silvestres no Brasil e os impactos causados na fauna brasileira. A transmissão do vírus ocorre através do contato com amostras contaminadas, a exemplo dos aerossóis, excretas e secreções de indivíduos infectados. Os sinais clínicos mais prevalentes são de ordem neurológica, entretanto, também podem ser identificadas manifestações respiratórias, cutâneas e gastrointestinais. Portanto, o diagnóstico consiste na avaliação da sintomatologia apresentada em conjunto com testes específicos, como isolamento viral, ELISA, imunofluorescência e RT-PCR. Atualmente, não existe tratamento específico. Desta forma, são realizados apenas cuidados paliativos. Os grandes carnívoros são os mamíferos mais ameaçados do mundo, sobretudo, em consequência dos impactos causados pela redução do habitat natural, associada à expansão territorial humana. As epidemias também justificam as altas taxas de mortalidades desses animais, o que pode estar relacionado com comportamentos sociais e de farejamento, assim como o crescente contato entre animais silvestres e domésticos devido à urbanização e à proximidade genética que os canídeos silvestres têm com os cães domésticos, tornando-os suscetíveis às infecções. Visto que a cinomose é uma patologia emergente em populações de carnívoros silvestres e que a presença de cães domésticos não vacinados em áreas de conservação representa um grande risco de contaminação, conclui-se que a não vacinação está diretamente associada à perpetuação do vírus no meio selvagem.

Distemper is a multisystem viral disease caused by a Morbillivirus. In Brazil, there are six species of wild canids, vulnerable to this disease. Therefore, the present work aims to develop a review on the situation of distemper in wild canids in Brazil and the impacts caused on the Brazilian fauna. The virus transmission occurs through contact with contaminated samples, such as aerosols, excreta, and secretions from infected individuals. The most prevalent clinical signs are neurological; however, respiratory, cutaneous and gastrointestinal manifestations can also be identified. Thus, the diagnosis consists of evaluating the symptoms presented together with specific tests, such as viral isolation, ELISA, immunofluorescence, and RT-PCR. Currently, there is no specific treatment. Therefore, only palliative care is performed. Large carnivores are the most threatened mammals in the world, mainly as a result of the impacts caused by the reduction of natural habitat, associated with human territorial expansion. Epidemics also justify the high mortality rates of these animals, which may be related to social and sniffing behaviors, as well as the increasing contact between wild and domestic animals due to urbanization and the genetic proximity that wild canids have with domestic dogs, making them susceptible to infections. Since distemper is an emerging pathology in populations of wild carnivores and the presence of unvaccinated domestic dogs in conservation areas represents a great risk of contamination, it is concluded that non-vaccination is directly associated with the perpetuation of the virus in the wild.

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Cutaneous hyperkeratosis is one of the many clinicopathological manifestations of canine distemper and is characterized by thickening and hardening of the skin, predominantly in nasodigital areas. Although this lesion may rarely affect other regions, this has been poorly characterized. Twelve dogs with canine distemper and cutaneous hyperkeratosis, necropsied at an anatomical pathology service, were investigated. Twenty-two cutaneous hyperkeratotic foci were observed on footpads (11/22), nasal planum (3/22), haired skin on the snout (2/22), periocular region (2/22), ventral abdomen (2/22), scrotum (1/22) and vulva (1/22). The dogs had one (5/12), two (4/12) or three (3/12) regions concomitantly affected. Orthokeratotic hyperkeratosis was a predominant histopathological feature in 17 dogs, occasionally accompanied by other lesions, including inclusion bodies (14/17), epidermal hyperplasia (9/17) and keratinocyte hydropic degeneration (6/17). Canine distemper virus antigen was expressed in at least one skin lesion in 10 dogs. Fourteen (14/17) hyperkeratotic foci were immunopositive while three (3/17) were immunonegative. Viral antigen expression was most common in the sweat glands (13/17), epidermis (11/17) and vascular endothelial cells or pericytes (8/17). Histological findings and antigen detection were similar among nasodigital and other regions. We emphasize the importance of clinicopathological recognition of these lesions for the initial suspicion of canine distemper, thereby facilitating early treatment.

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Abstract We present a case of Sarcoptes and canine distemper virus (CDV) infection in a white-nosed coati (Nasua narica) that was trapped in the dry tropical forest of Cerro Blanco reserve, located in the coastal region of Ecuador. Sarcoptic mange is a highly contagious and zoonotic disease with worldwide distribution that causes epidemics. Mange is produced by Sarcoptes mites that causes severe epidermal damage. Secondary infections and physiological constrictions without treatment can lead to death of the host. In addition, cooccurrence of canine distemper virus was detected via iiRT-PCR from serum samples. Physical analyses showed that 90% of the skin was affected by severe alopecia due to the sarcoptic mange infection. The presence of mites and histopathological analyses confirmed the diagnosis of infection. This coati was taken to a veterinary clinic and was fed every day, but it died after four days. This is the first report of sarcoptic mange and the first report of CDV in white-nosed coatis in South America. Further studies are needed in this region, to seek out other suspected cases, given the high capacity for disease transmission. Preventive actions to avoid epidemic and zoonotic episodes are needed.

Resumo Apresentamos um caso de Sarcoptes e infecção pelo vírus da cinomose canina (CDV) em um quati-do-nariz-branco (Nasua narica) que ficou preso na floresta tropical seca da reserva de Cerro Blanco, localizada na região costeira do Equador. A sarna sarcóptica é uma doença altamente contagiosa e zoonótica de distribuição mundial que causa epidemias. A sarna é produzida por ácaro do gênero Sarcoptes que causa graves danos epidérmicos. Infecções secundárias e constrições fisiológicas sem tratamento podem levar à morte do organismo. Além disso, a coocorrência do vírus da cinomose canina foi detectada, via iiRT-PCR, a partir de amostras de soro. As análises físicas mostraram que 90% da pele estava afetada por alopecia severa devido à infecção pelo ácaro da sarna sarcóptica. A presença de ácaros e análises histopatológicas confirmaram o diagnóstico de infecção. Esse quati foi levado a uma clínica veterinária e foi alimentado todos os dias, mas morreu após quatro dias. Esse é o primeiro relato de sarna sarcóptica e o primeiro relato de CDV em quatis-de-nariz-branco na América do Sul. São necessários mais estudos nessa região, para buscar outros casos suspeitos, dada a alta capacidade de transmissão da doença. Ações preventivas para evitar episódios epidêmicos e zoonóticos, são necessárias.

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Canine morbillivirus (CDV) is a viral agent that infects domestic dogs and a vast array of wildlife species. It belongs to the Paramyxoviridae family, genus Morbillivirus, which is shared with the Measles virus (MeV). Both viruses employ orthologous cellular receptors, SLAM in mononuclear cells and Nectin-4 in epithelial cells, to enter the cells. Although CDV and MeV hemagglutinin (H) have similar functions in viral pathogenesis and cell tropism, the potential interaction of CDV-H protein with human cellular receptors is still uncertain. Considering that CDV is classified as a multi-host pathogen, the potential risk of CDV transmission to humans has not been fully discarded. In this study, we aimed to evaluate both in silico and in vitro, whether there is a cross-species transmission potential from CDV to humans. To accomplish this, the CDV-H protein belonging to the Colombian lineage was modelled. After model validations, molecular docking and molecular dynamics simulations were carried out between Colombian CDV-H protein and canine and human cellular receptors to determine different aspects of the protein-protein interactions. Moreover, cell lines expressing orthologous cellular receptors, with both reference and wild-type CDV strains, were conducted to determine the CDV cross-species transmission potential from an in vitro model. This in silico and in vitro approach suggests the possibility that CDV interacts with ortholog human SLAM (hSLAM) and human Nectin-4 receptors to infect human cell lines, which could imply a potential cross-species transmission of CDV from dogs to humans.

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BACKGROUND: Human population expansion has increased the contact between domestic animals and wildlife, thereby increasing the transmission of infectious diseases including canine distemper virus (CDV). Here, we investigated the risk factors associated with CDV exposure in domestic and wild carnivores from the Janos Biosphere Reserve (JBR), Mexico. METHODS: A cross-sectional household questionnaire study was performed in four rural towns to investigate the risk factors associated with the presence of CDV in domestic and wild carnivores from the JBR, Mexico. In addition, we tested serum samples from 70 dogs and three wild carnivores, including one bobcat (Lynx rufus), one striped skunk (Mephitis mephitis) and one gray fox (Urocyon cinereoargenteus) for CDV antibodies using immunochromatographic and viral neutralization assays. RESULTS: Overall, 62% of domestic dogs were seropositive for CDV, and the presence of antibodies was significantly higher in free-roaming owned dogs than dogs with restricted movement. Among the wild carnivores, only the bobcat was seropositive. The rate of vaccination against CDV in dogs was low (7%), and there was a high rate of direct interactions between domestic dogs and wild carnivores. CONCLUSION: Our serological assays show that CDV is circulating in both domestic dogs and wild carnivores, suggesting cross-species transmission. Our finding of low vaccination rates, high number of unrestrained owned dogs and direct interactions between wildlife and domestic animals reported in the region may be perpetuating the high prevalence of the virus and increasing the risk of CDV transmission between wild and domestic carnivores. Therefore, long-term longitudinal studies are recommended in order to monitor infectious diseases at the domestic-wildlife interface in this highly biodiverse region.

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We examined the cerebellum and cerebrum of 4 vaccinated dogs, 3-60-mo-old, that displayed clinical signs of canine distemper virus (CDV) infection, and died 7-40 d after developing neurologic signs. The main histologic lesions were demyelination, gliosis, meningitis, perivascular lymphocytic cuffing, and inclusion bodies. These lesions were similar in all 4 cases regardless of the time since vaccination, except that meningoencephalitis and gliosis were subacute in 3 dogs and chronic in 1 dog. However, these differences did not appear to be related to their vaccination status. Immunohistologically, a CDV-positive immunoreaction was seen mainly in astrocytes, neurons and their axons, lymphocytes around and in the blood vessels of the pia mater and choroid plexus, ependymal cells of each ventricle, and the cells of the choroid plexus. The histologic and immunohistologic changes were similar in the cerebellum and cerebrum. The genetic characterization of the virus strains in 2 of these naturally occurring canine distemper cases confirmed that they were South American wild-type strains (Kiki and Uy251) belonging to the EU1/SA1 lineage. These strains are not included in the commercial CDV vaccines available in Uruguay.

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The extensive use of antibiotics is a leading cause for the emergence and spread of antimicrobial resistance (AMR) among dogs. However, the impact of using antibiotics to treat viral infections on AMR remains unknown. In this study, we compared the prevalence of extended-spectrum cephalosporin-resistant Enterobacterales (ESCR-E) between dogs with a suspected infection of canine parvovirus (CPV) and canine distemper (CDV) before and after treatment with third-generation cephalosporins. We found a higher prevalence of ESCR-E faecal carriage in dogs suspected of CPV (37%) and CDV (15%) compared to dogs with noninfectious pathologies (9%) even prior to the start of their treatment. A 7-day course of ceftriaxone or ceftiofur administrated to CPV and CDV-suspected dogs substantially increased their ESCR-E faecal carriage during treatment (85% for CPV and 57% for CDV), and 4 weeks after the treatment ended (89% for CPV and 60% for CDV) when dogs were back in their households. Most of the observed resistance was carried by ESCR-E. coli carrying blaCTX-M genes. Our results suggest the need to optimize prophylactic antibiotic therapy in dogs treated for a suspected viral infection to prevent ESCR-E emergence and spread in the community.

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Canine distemper virus (CDV) is one of the most significantinfectious disease threats to the health and conservation of free-ranging and captive wild carnivores. CDV vaccination using recombinant canarypox-based vaccines has been recommended for maned wolf (Chrysocyon brachyurus) after the failure of modified live vaccines that induced disease in vaccinated animals. Here, we report a CDV outbreak in a captive population of maned wolves that were previously vaccinated. Five juveniles and one adult from a group of seven maned wolves housed in an outdoor exhibit died in April-May 2013 in a zoo in the Metropolitan Region, Chile. Clinical signs ranged from lethargy to digestive and respiratory signs. Diagnosis of CDV was confirmed by histopathology, antibody assays, and viral molecular detection and characterization. The phylogenetic analyses of the nucleotide sequence of the H gene of the CDV genome identified in the two positive samples suggest a close relation with the lineage Europe 1, commonly found in South America and Chile. CDV infections in maned wolves have not been previously characterized. To the authors' best knowledge, this is the first report of the clinical presentation of CDV in a canine species previously immunized with a recombinant vaccine.