[Use of an immunoenzyme method for diagnosing canine distemper]

Analysis of the clinical data and laboratory studies brought the authors to a conclusion on the possibility of using dot solid-phase ELISA on nitrocellulose for rapid (1 h), simple, and specific detection of canine distemper virus. The method is sufficiently specific, helps specify the clinical diagnosis, and may be used in future for the creation of a commercial test system.

Detection of canine distemper viral antigen in foxes (Vulpes vulpes) in northwestern Spain

We describe the lesions of natural distemper in red foxes (Vulpes vulpes) in Spain. The avidin-biotin-peroxidase complex (ABC) technique and a monoclonal antibody against the nucleocapsid protein of canine distemper virus were successfully used to confirm canine distemper diagnosis.

Studies on manifestations of canine distemper virus infection in an urban dog population

An upsurge of canine distemper was recognized at the beginning of 1991 in the urban dog population of the Copenhagen area. The outbreak had the characteristics of a virulent morbillivirus introduction in a partly immune population, where the disease primarily was manifested in young individuals. Testing of single serum samples for the presence of canine distemper virus (CDV) IgM antibodies using an IgM ELISA confirmed current and recent CDV infections in an urban dog population, where the use of attenuated CDV vaccines was widespread. In 49 out of 66 sera from clinical cases suspected of canine distemper we detected CDV IgM antibodies, as compared to the detection of viral antigen by indirect immunofluorescence in 27 of 65 specimens of conjunctival cells. The antigenic make-up of isolates from acute and subacute clinical cases was investigated with a panel of 51 monoclonal antibodies directed against CDV and the related phocine distemper virus. The isolates exhibited an homogeneous reaction pattern and shared overall antigenic characteristics of the CDV prototype. The majority of cases were diagnosed among unvaccinated dogs and individuals with unknown or obscure vaccination record. However, severe clinical cases were also diagnosed in vaccinated individuals.

Canine distemper infection associated with acute nervous signs in dogs

Eight vaccinated dogs suddenly developed progressive ataxia, paresis or paralysis of short duration. A histopathological examination revealed a non-suppurative meningoencephalitis suggestive of a viral infection, and immunohistochemical examination confirmed the presence of canine distemper virus antigen in five of the dogs. Distemper had not been suspected from the clinical examination of the dogs.

Canine distemper virus infection and encephalitis in javelinas (collared peccaries)

Canine distemper virus has been isolated in dog lymphocyte cultures from the brains of three javelinas that became moribund with signs of encephalitis. Canine distemper viral antigen was demonstrated predominantly in neurons and morbillivirus-like structures were seen by electron microscopy in brains of diseased animals. Serological studies suggest that CDV infection may be common in javelinas.

Detection of IgM antibodies against canine distemper virus in dog and mink sera employing enzyme-linked immunosorbent assay (ELISA)

An enzyme-linked immunosorbent assay (ELISA) for the detection of IgM antibodies against canine distemper virus (CDV) in canine and mink serum is described. The diagnostic potential of this technique was evaluated by analyzing sera from natural or experimental infections in dog and mink and negative control sera. These results were compared with results obtained in the developed CDV IgG ELISA and in the virus neutralization test. The IgM test, which requires only a single serum specimen, is a useful method for diagnosing current or recent CDV infections in dog and mink.

Immunohistochemical demonstration of canine distemper virus antigen as an aid in the diagnosis of canine distemper encephalomyelitis

Brain tissue from 33 dogs with non-suppurative encephalitis was examined for evidence of canine distemper virus (CDV) encephalitis. Sections were examined for lesions, inclusion bodies, syncytial cells and CDV antigen using a double bridge unlabelled antibody enzyme technique. Histopathological lesions considered to be typical of granulomatous meningoencephalomyelitis were found in seven dogs. They all lacked inclusion bodies, syncytial cells and CDV antigen. The remaining 26 dogs all had histopathological lesions typical of CDV encephalitis. Inclusion bodies were found in 24 dogs, four of which also had syncytial cells and CDV antigen was detected immunocytochemically in 25. One dog had no inclusion bodies or syncytial cells and was immunohistochemically negative. Syncytial cells have been found to be of limited diagnostic value for the diagnosis of CDV encephalitis. While inclusion bodies proved to be a good diagnostic criterion for the confirmation of CDV infection, the immunohistochemical demonstration of CDV antigen proved to be superior. CDV antigen was more prevalent than inclusion bodies in tissue sections and much more easily detectable.

[Distemper as the cause of death in badgers in Austria]

A canine distemper virus infection of badgers in a hunting range in Austria is described. A badger which was shot after showing symptoms of rabies infection and one which was found dead were examined by gross pathology and parasitological, histological, bacteriological and virological methods. The examination for rabies was negative in both cases. The badger which was found dead histologically showed signs of a non purulent panencephalitis, the shot animal showed hyperaemia and oedema of the brain. No cytoplasmatic or nuclear inclusion bodies could be observed. The aetiologic viral diagnosis was achieved by immunofluorescence. Using two canine distemper-specific conjugates a typical granular fluorescence of different strength could be observed in organ sections. The bacterial examination showed in both cases a secondary infection with opportunistic pathogenic bacteria (haem. E. coli and Pseudomonas aeruginosa).

Detection of intracellular canine distemper virus antigen in mink inoculated with an attenuated or a virulent strain of canine distemper virus

Using an indirect immunofluorescence technique, the distribution of viral antigen in various tissues and blood mononuclear leukocytes was studied in wild mink, either vaccinated with an attenuated vaccine strain of canine distemper virus (CDV) or experimentally inoculated with the virulent Snyder-Hill strain of CDV. Viral antigen was detected in cells of the lymphoid system 6 to 12 days after vaccination. From 2 to 3 days after inoculation with the virulent strain, CDV antigen was demonstrated in cells of the lymphoid system and, during the incubation period, the antigen had spread to the epithelia and brain at days 6 and 12, respectively. In clinical cases of acute fatal canine distemper, the viral antigen was detected in a wide variety of tissues, including the cells of the lymphoid system, epithelial cells of skin, mucous membranes, lung, kidney, and cells of the CNS. The diagnostic importance of CDV antigen detection is discussed on the basis of these findings.

Natural infection with canine distemper virus in a Japanese monkey (Macaca fuscata)

A case of encephalitis in a Japanese monkey (Macaca fuscata) was examined histopathologically and serologically. The animal had brain lesions consisting of perivascular cuffs, malacia, inclusion bodies and giant cells. Monoclonal antibody to the nucleoprotein of canine distemper virus (CDV) stained the inclusions, and the distribution of the virus antigen was closely associated with that of the histological lesions. Serologically, all the 22 monkeys in the same group as the diseased monkey had relatively high titers of neutralizing antibody to CDV, but not to measles virus (MV). The pattern of the antibody titers to CDV and MV closely resembled that of cynomolgus monkeys experimentally inoculated with CDV, but differed from that of monkeys inoculated with MV. These findings suggest that an epidemic of CDV occurred in these Japanese monkeys, associated with one case of fatal viral encephalitis. This is believed to be the first report of a natural infection by CDV in non-human primates.

[Canine distemper: then and now]

Canine distemper was known as a severe systemic infection of dogs and other carnivores for some centuries now. Symptoms of the gastrointestinal and respiratory tracts are particularly prominent. Nervous symptoms are also regularly observed. A paper on canine distemper by J.C. van der Slooten appeared in Tijdschrift voor Veeartsenijkunde en Veeteelt in 1894, in which a number of features of this disease was discussed. This paper was also published in the present issue of Tijdschrift voor Diergeneeskunde (see page 309). On the basis of this paper, several developments are described, which contributed to our current knowledge of canine distemper. Particular attention is paid to the aetiology, pathogenesis and epizootiology as well as the prevention of distemper by vaccination.

Differential diagnosis of granulomatous meningoencephalomyelitis, distemper, and suppurative meningoencephalitis in the dog

Clinical differences were determined between granulomatous meningoencephalomyelitis, distemper, and suppurative meningoencephalitis in the dog. Dogs with granulomatous meningoencephalomyelitis had "head" signs on examination, which progressed to profound caudal fossa abnormalities, changes in mental status, and tetraparesis. Dogs with distemper had a gradual onset of posterior paresis; tetraparesis and occasional vestibular signs developed later in the course of disease. Dogs with suppurative meningoencephalitis had lethargy and anorexia at the time of examination, which progressed to nuchal rigidity, mental depression, tetraparesis, and profound alterations in consciousness. Analysis of cerebral spinal fluid was useful in distinguishing suppurative meningoencephalitis from the other 2 diseases. Twenty-seven cases of inflammatory disease of the CNS in dogs were reviewed. Comparisons of history, results of physical and neurologic examinations, ancillary data, and response to treatment were made. It appeared that certain clinical and neurologic features contributed to the diagnosis of these diseases.

Viral respiratory diseases

An overview of the more commonly encountered viral diseases of the dog and cat is presented. The reader is acquainted with the principles of antiviral therapy and the drugs that have been studied for use in animal viral respiratory diseases. An update on vaccination principles and guidelines is provided.

Syncytia formation: an aid in the diagnosis of canine distemper encephalomyelitis

Syncytia formation has been observed in response to experimental Canine Distemper Virus (CDV) infection in specific-pathogen-free Beagle dogs. Multinucleated giant cells are most frequently found in white matter lesions of the brain and in the anterior uvea of the eye. Lymph nodes and the lung are occasionally positive, while the leptomeninges will also rarely harbour syncytia. The mechanism of syncytia formation and their possible importance in the pathogenesis of the disease are briefly discussed. Widespread tissue syncytia formation is a feature of CDV infection which should assist in identifying cases of non-suppurative encephalitis in the dog caused by this agent.

Chronic encephalomyelitis caused by canine distemper virus in a Bengal tiger

A chronic progressive neurologic disease was observed and monitored for 18 months in a young, tamed Bengal tiger. Clinical, serologic, and neuropathologic evidence of canine distemper virus infection was seen. Clinical signs included convulsions, myoclonus, and slowly progressive ataxia. Marked increases in neutralizing antibodies against canine distemper virus were seen in the serum and cerebrospinal fluid. Neuropathologic findings were nonsuppurative meningoencephalomyelitis, with perivascular cuffing, demyelination, and inclusion bodies typical of canine distemper virus. It was concluded that, in light of this case and an earlier report of canine distemper in lion cubs, vaccination of this subgroup of carnivores with a killed vaccine may be beneficial if exposure to other animals susceptible to canine distemper is anticipated.

Immunoperoxidase study of canine distemper virus pneumonia

Forty-two cases of canine pneumonia were examined for the presence of canine distemper virus. For that purpose canine distemper virus inclusion bodies were located. The histopathological lesions were related to the presence of canine distemper antigen, as demonstrated with an immunoperoxidase technique. This technique was more sensitive for detecting canine distemper infection in lung tissue than was the study of inclusion bodies. Attention was also paid to combined infection with canine adenovirus and Bordetella bronchiseptica.

Serologic survey for canine distemper and infectious canine hepatitis in wolves in Alaska

Sera from 57 wolves (Canis lupus) in three areas of Alaska were evaluated for evidence of previous exposure to infectious canine hepatitis virus (ICHV) and canine distemper virus (CDV). Fifty-four sera (94.7%) were positive for ICHV exposure and four (7%) were positive for CDV exposure. All four CDV-reacting wolves also had titres to ICHV. The relatively common occurrence of ICHV exposure may be due to the greater resistance of ICHV to chemical and physical agents and its transmissibility via the urine of infected animals. The ICHV titres observed could indicate enzootic pathogenic ICHV, or exposure to the mildly pathogenic vaccine strain of CAV-1 through contact with the urine of domestic dogs. If CAV-1 is the original source of exposure, the titres could represent an ICHV-protected wolf population.