Pseudorabies virus infected with

Cross contamination of vaccines with other pathogens has also resulted in mortality and morbidity in animals. These incidents have included pseudorabies virus contaminated with pestivirus, Marek s disease virus contaminated with reticuloendotheliosis virus, contamination of cell lines and vaccines with bovine diarrhoea virus, bluetongue in dogs arising from contaminated live canine vaccine and clostridial disease in ruminants of 202 523 animals in affected herds, 41 767 were infected with Clostridium sordellii and 22 189 died, possibly as a result of a failure in a sterility test for detecting contaminants in a clostridial vaccine. 

Arsenicals were ineffective in controlling certain bacterial and viral infections. Mice experimentally infected with bacteria (Klebsiella pneumonias) or viruses (pseudorabies, encephalitis, encephalmyocarditis) showed a significant increase in mortality when treated with large doses of arsenicals compared to nonarsenic-treated groups (NAS 1977 Aranyi et al. 1985). 

Warner MS, Geraghty RJ, Martinez WM, Montgomery RI, Whitbeck JC, Xu R, Eisenberg RJ, Cohen GH, Spear PG (1998) A cell surface protein with herpesvims entry activity (HveB) confers susceptibility to infection by mutants of herpes simplex vims type 1, herpes simplex virus type 2, and pseudorabies virus. Virology 246 179-189. 

The virus reduction studies of the three process steps discussed here were performed with HFV-l, Bovine viral diarrhea virus (BVDV), Pseudorabies virus (PRV), Reovirus type 3 (Reo), Hepatitis A virus (HAV), and Porcine parvovirus (PPV). HIV-1 was included as a relevant enveloped virus, while BVDV and PRV were tested as specific model viruses for HCV and HBV, respectively (Table 1). Reo was chosen as a non-specific model non-enveloped virus, HAV was included as a relevant virus and PPV was used as a surrogate for human parvovirus B19. All viruses were propagated using standard cell culture conditions. " The appropriate cell lines were infected, at a low multiplicity of infection, and incubated until 4-1- cytopathic effects were observed. The infected cells were frozen and thawed three times to release virus, centrifuged at low speed to remove cell debris and the clarified supernatants were removed for use as virus spikes. 

The earliest studies using radioactive precursors to measure the overall rates of synthesis of nucleic acids showed that in growing rabbit kidney cells infected with pseudorabies virus (PRV) the rate of DNA synthesis declined steadily over the first 5 hr and then increased but the total quantity of DNA in the cells did not change significantly (Kaplan and Ben-Porat, 1960). Newton et al. (1962) observed a similar decline in incorporation of radioactive thymidine during the first 6 hr of infection with HSV followed by a gradual rise to 10 hr after infection. The decline was accompanied by release of radioactive material from cells prelabeled before infection with [ HJthymidine (Newton, 1964). 

Hamada, C., and Kaplan, A. S., 1965, Kinetics of synthesis of various types of antigenic proteins in cells infected with pseudorabies virus, J. Bacteriol. 89 1328. 

Kennedy, I. M., Stevely, W. S., and Leader, D. P., 1981, Phosphorylation of ri-bosomal proteins in hamster fibroblasts infected with Pseudorabies virus or Herpes Simplex virus, J. Virol. 39 359. 

McGrath, B. M., and Stevely, W. S., 1980, The characteristics of the cell-free translation of mRNA from cells infected with the herpes virus Pseudorabies virus, J. Gen. Virol. 49 323. 

Preliminary studies with azauridine suggest that this material was effective for the treatment of herpes simplex and zoster infections of the human eye (69). Rabbits infected with vaccinia virus vaccine were com-pletely protected from pustule formation and erythema by 2-3 grams of compound injected IV (70). This material apparently has a low order of toxicity. 5-Bromo-2-deoxyuridine was found to inhibit a new virus, equine herpes 3, in rabbit kidney cells as well as pseudorabies, a DMA. virus, whereas vesicular stomatitis, an RNA virus, was resistant (71). A large number of nucleosides have been synthesized and tested in various systems for antiviral activity. 1-p-D-Arabinofuranosylcytosine (cytarabine ara-C) blocked DNA synthesis of herpes-infected cells (72) while a number of structurally related compounds showed some antiviral activity, although less than the parent compound (73,74,75,76). It is still too early to determine the ultimate value of these newer agents as "antiviral" drugs. 

Significant antiviral ejfectivity was shown in vitro for titanocene dichloride (I) against numerous DNA and RNA viruses in the extracellular phase Typical examples of viruses, which were inhibited by direct contact with I and lost infectivity up to 100%, were orthopoxvirus (vaccinia) and herpes virus (pseudorabies) as DNA viruses, and rhabdovirus (vesicular stomatitis), paramyxovirus (Newcastle disease) and diverse orthomyxoviruses (e.g. influenza A and B) as RNA viruses. A comparable antiviral effect against herpes viruses was detectable after application of the ferricenium salt whereas, on the other hand, vanadocene dichloride (11) and molybdenocene dichloride (V) failed to show antiviral activity under the same experimental conditions. 

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