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Experiments that exposed influenza virus (H5N1)–infected cats to susceptible dogs did not result in intraspecies or interspecies transmission. Infected dogs showed increased body temperatures, viral RNA in pharyngeal swabs, and seroconversion but not fatal disease.

International audience; Equine Arteritis Virus (EAV) belongs to the Arteriviridae and causes viral arteritis in horses. In an attempt to develop novel and save therapies against the infection it was tested whether EAV is susceptible to RNA interference (RNAi) in an equine in vitro system. Horse cells were transfected with chemically synthesized small interfering RNA oligonucleotides (siRNAs) and challenged with EAV. Application of these siRNAs led to a significant protection of the cells, and virus titers decreased drastically. siRNAs derived from DNA plasmids expressing small hairpin RNAs (shRNAs) were also effective. The protection was most pronounced with two siRNAs targeting the open reading frame 1 (coding for non-structural proteins), whereas siRNAs targeting sequences for several structural proteins had less or no effect. In addition, it was investigated whether RNAi could be used to treat cells with an already established viral infection. Only application of the siRNAs shortly after viral challenge led to significant survival rates of the cells, whereas transfection at later time points caused much less benefit for the cells. These findings are discussed in a perspective of using RNAi as a therapeutic approach to combat EAV.

Highly pathogenic avian influenza virus (HPAIV) H5N1 of Asian origin continues to circulate in poultry and wild birds, causing considerable concern for veterinary and public health in Asia, Europe and Africa. Natural transmission of HPAIV H5N1 from poultry to humans, resulting in infections associated with high mortality, and from poultry or wild birds to large felids and domestic cats has been reported. Experimental infection of cats with HPAIV H5N1 derived from a human patient resulted in lethal disease. The role of cats in the adaptation of HPAIV H5N1 to mammals and vaccination regimens for the eventual protection of cats, however, remain to be elucidated. Here, it was shown that cats can be protected against a lethal high-dose challenge infection by an inactivated, adjuvanted heterologous H5N6 avian influenza virus vaccine. The challenge HPAIV H5N1 was derived from a naturally infected cat. In non-vaccinated cats, low-dose exposure resulted in asymptomatic infections with minimal virus excretion. As diseased cats can transmit the infection to naïve contact animals, the epidemiological role of H5N1-infected cats in endemically infected areas as a link between wild birds, poultry and humans needs close inspection, and vaccination of cats should be considered to reduce possible human exposure.

Suspect field cases of BSE infection (displaying clinical signs) were examined for possible alterations of cytokine/autacoid plasma levels and were compared to control cases (not displaying clinical signs of BSE infection). Interferon gamma (IFN-gamma) plasma levels were demonstrated as being elevated in all suspected field cases of BSE infection (irrespective of BSE status; determined via postmortem histopathological examination). We demonstrated that plasma IFN-gamma levels were significantly (P0.005) higher in suspect cases of BSE infection than in control cases. BSE-positive prostaglandin-E(2), (PGE(2)) plasma levels were demonstrated as being elevated 1.25-fold above BSE-negative cases and 2.22-fold above control cases. No significant (P0.5) increase in PGE(2)plasma levels was recorded between BSE-positive and -negative. IFN-gamma and PGE(2)plasma levels were examined using commercially available ELISA assay. The results presented in this publication are the first demonstration of alteration in immune state in animals with BSE.