Evaluation of the Efficacy of Commercial Disinfectants against African Swine Fever Virus.

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.

African Swine Fever Virus Plaque Assay and Disinfectant Testing.

Quantifying the titer of African swine fever virus is critical for disease control, viral infection studies, and disinfectant efficacy tests. Techniques such as real-time PCR and virus isolation provide an understanding as to whether viral genome is present or gives a qualitative assessment of live viral presence in a sample respectively, but neither provide a quantitative measurement of live virus. Here we describe a plaque assay for the titration of a Vero-adapted African swine fever virus strain (BA71V) and describe how to apply this method to determine disinfectant efficacy.

Outbreak of African horse sickness in Thailand, 2020.

African horse sickness was confirmed in horses in Thailand during March 2020. The virus was determined to belong to serotype 1 and is phylogenetically closely related to isolates from South Africa. This is the first incidence of African horse sickness occurring in South East Asia and of serotype 1 outside of Africa.

BTV-14 Infection in Sheep Elicits Viraemia with Mild Clinical Symptoms.

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.

Complete Coding Sequence of a Novel Bluetongue Virus Isolated from a Commercial Sheeppox Vaccine.

The full genome sequences of two isolates of bluetongue virus (BTV) from a commercial sheeppox vaccine were determined. Strain SPvvvv/02 shows low sequence identity to its closest relative, strain BTV-26 KUW2010/02, indicating the probable detection of a novel BTV genotype, whereas strain SPvvvv/03 shows high sequence identity to strain BTV-28/1537/14.

Evidence of reduced viremia, pathogenicity and vector competence in a re-emerging European strain of bluetongue virus serotype 8 in sheep.

The outbreak of bluetongue virus (BTV) serotype 8 (BTV-8) during 2006-2009 in Europe was the most costly epidemic of the virus in recorded history. In 2015, a BTV-8 strain re-emerged in France which has continued to circulate since then. To examine anecdotal reports of reduced pathogenicity and transmission efficiency, we investigated the infection kinetics of a 2007 UK BTV-8 strain alongside the re-emerging BTV-8 strain isolated from France in 2017.

Using shared needles for subcutaneous inoculation can transmit bluetongue virus mechanically between ruminant hosts.

Bluetongue virus (BTV) is an economically important arbovirus of ruminants that is transmitted by Culicoides spp. biting midges. BTV infection of ruminants results in a high viraemia, suggesting that repeated sharing of needles between animals could result in its iatrogenic transmission.

The Dimerization State of the Mammalian High Mobility Group Protein AT-Hook 2 (HMGA2).

The mammalian high mobility group protein AT-hook 2 (HMGA2) is a chromosomal architectural transcription factor involved in cell transformation and oncogenesis. It consists of three positively charged "AT-hooks" and a negatively charged C-terminus. Sequence analyses, circular dichroism experiments, and gel-filtration studies showed that HMGA2, in the native state, does not have a defined secondary or tertiary structure.

Real-time reverse transcriptase PCR for the detection of bluetongue virus.

In recent years, real-time reverse transcription polymerase chain reaction (rRT-PCR) has become one of the most widely used methods for the diagnosis of infectious pathogens. The combined properties of high sensitivity, specificity, and speed, along with a low contamination risk, have made real-time PCR technology a highly attractive alternative to more conventional diagnostic methods. Numerous robust rRT-PCR systems have been developed and validated for important epizootic diseases of livestock, and in this chapter we describe an rRT-PCR protocol for the detection of bluetongue virus.

Characterization of sheep pox virus vaccine for cattle against lumpy skin disease virus.

Lumpy skin disease is of significant economic impact for the cattle industry in Africa. The disease is currently spreading aggressively in the Near East, posing a threat of incursion to Europe and Asia. Due to cross-protection within the Capripoxvirus genus, sheep pox virus (SPPV) vaccines have been widely used for cattle against lumpy skin disease virus (LSDV).

Vaccination of horses with a recombinant modified vaccinia Ankara virus (MVA) expressing African horse sickness (AHS) virus major capsid protein VP2 provides complete clinical protection against challenge.

African horse sickness virus (AHSV) is an arthropod-borne pathogen that infects all species of equidae and causes high mortality in horses. Previously, a recombinant modified vaccinia Ankara (MVA) virus expressing the protein VP2 of AHSV serotype 4 was shown to induce virus neutralising antibodies in horses and protected interferon alpha receptor gene knock-out mice (IFNAR -/-) against virulent AHSV challenge. This study builds on the previous work, examining the protective efficacy of MVA-VP2 vaccination in the natural host of AHSV infection.

Evidence for transmission of bluetongue virus serotype 26 through direct contact.

The aim of this study was to assess the mechanisms of transmission of bluetongue virus serotype 26 (BTV-26) in goats. A previous study, which investigated the pathogenicity and infection kinetics of BTV-26 in goats, unexpectedly revealed that one control goat may have been infected through a direct contact transmission route. To investigate the transmission mechanisms of BTV-26 in more detail an experimental infection study was carried out in which three goats were infected with BTV-26, three goats were kept uninfected, but were housed in direct contact with the infected goats, and an additional four goats were kept in indirect contact separated from infected goats by metal gates.

Early changes in cytokine expression in peste des petits ruminants disease.

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.

Peste des petits ruminants infection among cattle and wildlife in northern Tanzania.

We investigated peste des petits ruminants (PPR) infection in cattle and wildlife in northern Tanzania. No wildlife from protected ecosystems were seropositive. However, cattle from villages where an outbreak had occurred among small ruminants showed high PPR seropositivity, indicating that spillover infection affects cattle.