Canine distemper

A number of animal diseases caused by viruses involve primary demyelination and often are associated with inflammation. These diseases are studied as animal models, which may provide clues about how a viral infection could lead to immune-mediated demyelination in humans [1, 5, 6]. Canine distemper virus causes a demyelinating disease, and the lesions in dog brain show a strong inflammatory response with some similarities to acute disseminated encephalomyelitis in man [ 1 ]. Visna is a slowly progressive demyelinating disease of sheep caused by a retrovirus [ 1 ]. 

King, D.P. et al., The use of monoclonal antibodies specific for seal immunoglobulins in an enzyme-linked immunosorbent assay to detect canine distemper virus-specific immunoglobulin in seal plasma samples, J. Immuno. Methods, 160, 163, 1993. 

Concentrations of V, Mn, Fe, Cr, Co, Cu, Zn, As, Se, Mo, Ag, Cd, Tl, Hg, Pb, and organic mercury (Org-Hg) were determined in liver, kidney, and muscle of healthy Caspian seals (Phoca caspica) collected in 1998. These concentrations were compared with those of seals infected with canine distemper virus (CDV) found stranded along the coastal areas in 2000 (Table 1). Concentrations of toxic elements (As, Ag, Cd, Tl, Hg, Pb, and Org-Hg) in Caspian seals stranded in 2000 were comparable or lower than those of samples collected in 1998 and in other pinnipeds. Thus it may be inferred that these elements were not the causative agents in the deaths of the seals. In contrast, concentrations of Zn and Fe were much higher in diseased Caspian seals than those in other pinnipeds. Zinc concentrations in all tissues of Caspian seals also increased during 1993-2000. Furthermore, negative correlations were found between blubber thickness and hepatic and renal Zn concentrations. These results imply the disturbance... 

The salts of heterylbiguanides are generally active 8) against viruses, and are of unusually low toxicity. They appear to be useful against influenza, herpes zoster, smallpox, Newcastle disease and canine distemper. Xylylbiguanides are also active (7/2) against influenza, and isopropylbiguanide hydrochloride inhibits Lee influenza virus in chick embryos [740). 

The paramyxovirus group includes the causative viruses of mumps, measles, parainfluenza, Newcastle disease, canine distemper, and several other diseases. These viruses are generally larger than the myxoviruses, are enveloped and pleomorphic, and contain one molecule of single-stranded RNA. 

The lipopeptide vaccine described in this study consists of a CD4+ helper T-cell epitope ([T]) and a B-cell epitope ([B]). These two epitopes are separated by a lysine residue (K) to which is attached the lipid moiety via two serine residues (Fig. IB). The CD4+ T-helper epitope KLIPNASLIENCTKAEL used is derived from the fusion protein of the morbillivirus canine distemper virus (34) and is recognized by T cells from BALB/c and C57BL6 mouse strains (4). The B-cell epitope is LHRH and has the sequence HWYSGLRPG. The presence of anti-LHRH antibodies can render vaccinated animals sterile. 

Ghosh, S., Walker, J., and Jackson, D.C. (2001) Identification of canine helper T-cell epitopes from the fusion protein of canine distemper virus. Immunology 104(1), 58-66. 

The stability of freeze-dried bacteria depends on the duration of incubation prior to freeze-drying, i.e., the condition of the bacterial cell [8-11]. The same holds true for viruses. Canine distemper virus, for example, shows some delicacy upon... 

Table 1 Canine Distemper Virus Variation of the Infectivity Titer after Freeze-Drying and Storage at 37°C...

The deep-freezing rate may also play a role in the stability of the freeze-dried vaccine as demonstrated by trials carried out on the associated vaccine containing modified canine distemper viruses and viruses of infectious canine hepatitis. 

Table 3 Vaccine for Canine Distemper and Infectious Canine Hepatitis Appearance and Evolution of Residual Moisture and Infectivity Titer Throughout the Storage Period at 5°C...

Table 4 shows the progression of the residual moisture of the canine distemper vaccine for various temperatures and desorption durations. At a similar temperature, increasing the desorption duration decreases the residual moisture level. For similar durations of desorption, the decrease in temperature translates to... 

Table 4 Canine Distemper Vaccine Influence of Temperature and of Duration of Desorption on the Residual Moisture of the Freeze-Dried Product...

Bovine brucellosis Canine distemper Poultry infectious bronchitis... 

The vaccine against canine distemper also has an optimal residual moisture level at which an optimal freeze-drying efficiency can be obtained this optimum is located at approximately 2% (Figure 4). Stability during storage appears to be improved by a residual moisture of approximately the same order (1.8% Figure 5). 

Figure 8 shows the evolution of the residual moisture of the canine distemper vaccine. Its is about four samples with residual moisture levels varying between 1.8% and 6.4%. The samples were stored at 5°C 3°C, and residual moisture measurements were taken on a regular basis. 

Let us consider the progression of the infectivity titer of the canine distemper vaccine stored at three different temperatures 6°C, 22°C, 37°C (Figure 10). The kinetics of decrease of infectivity for each storage temperature are calculated. By comparing these kinetics to various decreasing models, the only acceptable model is the one representing the simultaneous evolution of two exponential kinetics that could correspond to the existence of two products with different thermostabilities. 

Table 5 Canine Distemper Vaccine Variation in the Infectivity Titer According to Sealing Atmosphere and Storage Temperature...

Griot C, Burge T, Vandevelde M, Peterhans E (1989) Antibody-induced generation of reactive oxygen radicals by brain macrophages in canine distemper encephalitis A mechanism for bystander demyelination. Acta Neuropatliol (Beri) 78 396- 03. 

Table VII. Recovery Rates Among Dogs Treated with Ascorbic Acid for Canine Distemper Complex...

The most compelling evidence against a microbial etiology is the fact that no single infectious agent has been identified as the cause of MS. Many possible agents have been implicated, including mycoplasma, spirochetes, rabies virus, herpes simplex, canine distemper virus, coronavirus, human T-cell leukemia virus type I (HTLV-I), MS-associated retrovirus, measles, and most recently, human herpes virus type 6 (HHV-6) and Chlamydia pneumoniae However, to date, no causal relationship has been established. ... 

Prophylactically active agaiust a wide range of viruses, including those causing canine distemper, lymphomatosis in fowl, shipping fever in cattle, transmissible gastroenteritis iu swine, and coryza and other upper respiratory illnesses, as well as against ECHO viruses, enteroviruses in monkeys, MM neurotropic virus, Semliki Forest virus, and NEF 1 poliomyelitis virus. Antitumor activity demonstrated in experimental leukemia and sarcoma. 

Bencsik, A., Malcus, C., Akaoka, H., Giraudon, P., Belin, M.F., and Bernard, A. 1996. Selective induction of cytokines in mouse brain infected with canine distemper virus Stmctural, cellular and temporal expression. J. Neuroimmunol. 65, 1-9. 

Bernard, A., Zwingelstein, G., Meister, R., and Wild, T.F. 1988. Hyperinsulinemia induced by canine distemper vims infection of mice and its correlation with the appearance of obesity. Comp. Biochem. Physiol. B91, 691-696. 

Bernard, A., Fevre-Montange, M., Giraudon, P., Hardin, H., Wild, T.F., and Belin, M.F. 1991. Demonstration of viral proteins and RNA in hypothalamus of mice infected by canine distemper vims. C. R Acad. Sci. Ill 313, 545-551. 

Hall, W.W., Lamb, R.A., and Choppin, P.W. 1980. The polypeptides of canine distemper virus Synthesis in infected cells and relatedness to the polypeptides of other morbilliviruses. Virology 100, 433 49. Herden, C., Herzog, S., Richt, J.A., Nesseler, A., Christ, M., Failing, K., and Frese, K. 2000. Distribution of Boma disease virus in the brain of rats infected with an obesity-inducing virus strain. Brain Pathol 10, 39-48. 

Leisewitz, A.L., Carter, A., van Vuuren, M., and van Blerk, L. 2001. Canine distemper infections, with special reference to South Alrica, with a review of the literature. J. S. Afr. Vet. Assoc. 72, 127-136. 

Sixt, N., Cardoso, A., Vallier, A., FayoUe, J., Buckland, R., and Wild, T.F. 1998. Canine distemper vims DNA vaccination induces humoral and cellular immunity and protects against a lethal intracerebral challenge. J. ViroL 8472 476. 

Summers, B.A. and Appel, M.J. 1994. Aspects of canine distemper virus and measles virus encepha-lomyeUtis. Neuropathol Appl Neurobiol 20, 525-534. 

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