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Next generation vaccines have the capability to contribute to and revolutionise the veterinary vaccine industry. African horse sickness (AHS) is caused by an arbovirus infection and is characterised by respiratory distress and/or cardiovascular failure and is lethal to horses. Mandatory annual vaccination in endemic areas curtails disease occurrence and severity. However, development of a next generation AHSV vaccine, which is both safe and efficacious, has been an objective globally for years. In this study, both AHSV serotype 5 chimaeric virus-like particles (VLPs) and soluble viral protein 2 (VP2) were successfully produced in Nicotiana benthamiana ΔXT/FT plants, partially purified and validated by gel electrophoresis, transmission electron microscopy and liquid chromatography-mass spectrometry (LC-MS/MS) based peptide sequencing before vaccine formulation. IFNAR -/- mice vaccinated with the adjuvanted VLPs or VP2 antigens in a 10 µg prime-boost regime resulted in high titres of antibodies confirmed by both serum neutralising tests (SNTs) and enzyme-linked immunosorbent assays (ELISA). Although previous studies reported high titres of antibodies in horses when vaccinated with plant-produced AHS homogenous VLPs, this is the first study demonstrating the protective efficacy of both AHSV serotype 5 chimaeric VLPs and soluble AHSV-5 VP2 as vaccine candidates. Complementary to this, coating ELISA plates with the soluble VP2 has the potential to underpin serotype-specific serological assays., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: ‘Plant-produced chimaeric Orbivirus VLPs underpinning the development of the VLP vaccine was patented (PCT/IB2017/052236, PCT publication number WO2017/182958, US 11,053,509 B2, 2021 granted) with co-inventors from CSIR (Dr Rutkowska, Dr Stark and Dr O’Kennedy), OBP (Dr Mokoena) and inventors from the University of Cape Town whilst the design of the plant-produced soluble VP2 is proprietary to CSIR. A provisional patent protecting the design of the plant-produced AHS VP2 fusion protein and uses thereof, filed (Inventors: MM O’Kennedy and Y Lemmer)., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Experimental infection studies with bluetongue virus (BTV) in the mammalian host have a history that stretches back to the late 18th century. Studies in a wide range of ruminant and camelid species as well as mice have been instrumental in understanding BTV transmission, bluetongue (BT) pathogenicity/pathogenesis, viral virulence, the induced immune response, as well as reproductive failures associated with BTV infection. These studies have in many cases been complemented by in vitro studies with BTV in different cell types in tissue culture. Together these studies have formed the basis for the understanding of BTV-host interaction and have contributed to the design of successful control strategies, including the development of effective vaccines. This review describes some of the fundamental and contemporary infection studies that have been conducted with BTV in the mammalian host and provides an overview of the principal animal welfare issues that should be considered when designing experimental infection studies with BTV in in vivo infection models. Examples are provided from the authors' own laboratory where the three Rs (replacement, reduction and refinement) have been implemented in the design of experimental infection studies with BTV in mice and goats. The use of the ARRIVE guidelines for the reporting of data from animal infection studies is emphasized., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Towards understanding the molecular epidemiology of a severe dog rabies epidemic in the KwaZulu Natal province of South Africa, we analyzed a variable 592 nucleotide genome sequence domain of 170 rabies viruses from KwaZulu Natal and surrounding regions. Viruses from the KwaZulu Natal and Eastern Cape provinces belonged to a unique lineage, circulating as two independent and expanding epidemiological cycles. The first presented as closely related dog cycles along the eastern coastal regions of the two provinces, while the second, in northern KwaZulu Natal, has entered into at least one wildlife reservoir, the black backed jackal. We underline the success and opportunism of rabies in southern Africa, in a likely reflection of the emergence and radiation of rabies in new host species and locales throughout the larger continent as a whole.