Peste des petits ruminants is a viral disease of sheep and goats that has spread through most of Africa as well as the Middle East and the Indian subcontinent. Although, the spread of the disease and its economic impact has made it a focus of international concern, relatively little is known about the nature of the disease itself. We have studied the early stages of pathogenesis in goats infected with six different isolates of Peste des petits ruminants virus representing all four known lineages of the virus. No lineage-specific difference in the pathogenicity of the virus isolates was observed, although there was evidence that even small numbers of cell culture passages could affect the degree of pathogenicity of an isolate. A consistent reduction in CD4+ T cells was observed at 4 days post infection (dpi). Measurement of the expression of various cytokines showed elements of a classic inflammatory response but also a relatively early induction of interleukin 10, which may be contributing to the observed disease.
African swine fever (ASF) is an economically important disease due to high morbidity and mortality rates and the ability to affect all ages and breeds of pigs. Biosecurity measures to prevent the spread of the causative agent, African swine fever virus (ASFV), include prescriptive cleaning and disinfection procedures. The aim of this study was to establish the biocidal effects of twenty-four commercially available disinfectants including oxidizing agents, acids, aldehydes, formic acids, phenol, and mixed-class chemistries against ASFV. The products were prepared according to the manufacturer’s instructions and a suspension assay was performed with ASFV strain, BA71V using Vero cells (African green monkey cells) to test efficacy in reducing ASFV infection of cells. Generally, disinfectants containing formic acid and phenolic compounds, as well as oxidizing agents reduced viral titers of ASFV by over 4 log10 at temperatures ranging from 4 °C to 20 °C. Hydrogen peroxide, aldehyde, and quaternary ammonium compounds containing disinfectants were cytotoxic, limiting the detection of viral infectivity reductions to less than 4 log10. These preliminary results can be used to target research on disinfectants which contain active ingredients with known efficacy against ASFV under conditions recommended for the country where their use will be applied.
In 2011, Bluetongue virus serotype 14 (BTV-14) was detected in Russia during routine surveillance, and was subsequently found in a number of European countries. The strain had high sequence similarity to a BTV-14 vaccine strain. We aimed to determine the risk of this BTV-14 strain causing disease in a UK sheep breed. Four Poll Dorset sheep were infected with a Polish isolate of BTV-14 and infection kinetics were monitored over 28 days. BTV RNA was detected in EDTA blood by 4 days post-infection (dpi) and remained detectable at 28 days post-infection (dpi). Peak viraemia occurred at 6 and 7 dpi with Ct values ranging between 24.6 and 27.3 in all infected animals. BTV antibodies were detected by 10 dpi using a commercial ELISA and neutralising antibodies were detected from 10 dpi. BTV was isolated between 6 and 12 dpi. All infected sheep developed mild clinical signs such as reddening of conjunctiva and mucosal membranes, with one sheep demonstrating more overt clinical signs. Two uninoculated control animals remained clinically healthy and did not have detectable BTV RNA or antibodies. The overall mild clinical symptoms caused by this BTV-14 in this highly susceptible sheep breed were in accordance with the asymptomatic infections observed in the affected countries.