Widespread Reassortment Contributes to Antigenic Shift in Bluetongue Viruses from South Africa

Bluetongue (BT), a viral disease of ruminants, is endemic throughout South Africa, where outbreaks of different serotypes occur. The predominant serotypes can differ annually due to herd immunity provided by annual vaccinations using a live attenuated vaccine (LAV). This has led to both wild-type and vaccine strains co-circulating in the field, potentially leading to novel viral strains due to reassortment and recombination. Little is known about the molecular evolution of the virus in the field in South Africa. The purpose of this study was to investigate the genetic diversity of field strains of BTV in South Africa and to provide an initial assessment of the evolutionary processes shaping BTV genetic diversity in the field. Complete genomes of 35 field viruses belonging to 11 serotypes, collected from different regions of the country between 2011 and 2017, were sequenced. The sequences were phylogenetically analysed in relation to all the BTV sequences available from GenBank, including the LAVs and reference strains, resulting in the analyses and reassortment detection of 305 BTVs. Phylogenomic analysis indicated a geographical selection of the genome segments, irrespective of the serotype. Based on the initial assessment of the current genomic clades that circulate in South Africa, the selection for specific clades is prevalent in directing genome segment reassortment, which seems to exclude the vaccine strains and in multiple cases involves Segment-2 resulting in antigenic shift

"Akademisches Schwarmverhalten“ und globale Notlagen : Gleichberechtigte Süd-Nord-Forschungspartnerschaften zur Förderung einer hochwertigen Bildung in unterschiedlichen Kontexten und Kulturen

In this article we apply an Afrocentric Resilience Theory (relationship-resourced resilience) to the domain of education research partnerships. We posit academic flocking as an equitable research partnership approach aimed at developing education knowledge that responds to collective distress and supports collective quality education. We provide support for our supposition regarding academic flocking by overviewing the mutually beneficial development of an online, home-based learning resource with relevance in two transnational contexts and cultures, South Africa and the United States of America. Whereas the context of the argument is a COVID-19 related global need for evidence-based education resources, conceptually we draw on lenses of resilience and emancipatory, democratising methodology to make sense of academic flocking as a fundamental structure for research partnership equity and relevant education innovation. As such, academic flocking holds value as a transformative alternative for South-North researcher partnerships in generating useful, quality educational innovations to address critical needs.In diesem Beitrag wenden wir eine afrozentrische Resilienztheorie (beziehungsgestützte Resilienz) auf einen Ansatz der Bildungsforschungspartnerschaften an. Wir stützen uns auf die Annahme, dass „akademisches Flocking“ (Schwarmverhalten) eine Grundlage für gleichberechtigte Forschungspartnerschaften bildet. Der Ansatz zielt darauf ab, Wissen über Bildung zu generieren, das auf kollektive Notlagen reagiert und kollektive Prozesse der Qualitätsbildung unterstützt. Wir untermauern unsere Annahme über „akademisches Flocking“, indem wir einen Überblick über die für beide Seiten vorteilhafte Entwicklung einer Online-Lernressource geben, die zu Hause eingesetzt werden kann. Dieser Ansatz wurde in zwei transnationalen Kontexten und Kulturen – Südafrika und den Vereinigten Staaten von Amerika – erprobt. Kontext der Argumentation ist der von der COVID-19-Pandemie verstärkt sichtbar gewordene globale Bedarf an der Bereitstellung evidenzbasierter Bildungsressourcen. Konzeptionell stützen wir uns auf resilienztheoretische Sichtweisen und eine emanzipatorische, demokratiefördernde Perspektive, wodurch „akademisches Flocking“ als ein vielversprechender Ansatz für ausgewogene Forschungspartnerschaften zur Begleitung relevanter Bildungsinnovation sichtbar wird. Insbesondere bei Süd-Nord-Forschungspartnerschaften bietet sich hier eine nützliche, qualitativ hochwertige Grundlage für die kollaborative Entwicklung von wissenschaftlich unterstützten Bildungsinnovationen.https://link.springer.com/journal/11618hj2023Educational Psycholog

Possible over-wintering of bluetongue virus in Culicoides populations in the Onderstepoort area, Gauteng, South Africa

Several studies have demonstrated the ability of certain viruses to overwinter in arthropod vectors. The over-wintering mechanism of bluetongue virus (BTV) is unknown. One hypothesis is over-wintering within adult Culicoides midges (Diptera; Ceratopogonidae) that survive mild winters where temperatures seldom drop below 10 °C. The reduced activity of midges and the absence of outbreaks during winter may create the impression that the virus has disappeared from an area. Light traps were used in close association with horses to collect Culicoides midges from July 2010 to September 2011 in the Onderstepoort area, in Gauteng Province, South Africa. More than 500 000 Culicoides midges were collected from 88 collections and sorted to species level, revealing 26 different Culicoides species. Culicoides midges were present throughout the 15 month study. Nine Culicoides species potentially capable of transmitting BTV were present during the winter months. Midges were screened for the presence of BTV ribonucleic acid (RNA) with the aid of a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay. In total 91.2% of midge pools tested positive for BTV RNA. PCR results were compared with previous virus isolation results (VI) that demonstrated the presence of viruses in summer and autumn months. The results indicate that BTV-infected Culicoides vectors are present throughout the year in the study area. Viral RNA-positive midges were also found throughout the year with VI positive midge pools only in summer and early autumn. Midges that survive mild winter temperatures could therefore harbour BTV but with a decreased vector capacity. When the population size, biting rate and viral replication decrease, it could stop BTV transmission. Over-wintering of BTV in the Onderstepoort region could therefore result in re-emergence because of increased vector activity rather than reintroduction from outside the region

Complete Genome Sequences of Virus Strains Isolated from Bottle A of the South African Live Attenuated Bluetongue Virus Vaccine

This is a report of the complete genome sequences of plaque-selected isolates of five virus strains included in bottle A of the South African Onderstepoort Biological Products commercial live attenuated bluetongue virus vaccine

Widespread reassortment contributes to antigenic shift in Bluetongue viruses from South Africa

DATA AVAILABIITY: Information on the country of origin, year of isolation, and GenBank accession number for each of the 98 genomes used in this study is provided in Supplementary Table S1.Bluetongue (BT), a viral disease of ruminants, is endemic throughout South Africa, where outbreaks of different serotypes occur. The predominant serotypes can differ annually due to herd immunity provided by annual vaccinations using a live attenuated vaccine (LAV). This has led to both wild-type and vaccine strains co-circulating in the field, potentially leading to novel viral strains due to reassortment and recombination. Little is known about the molecular evolution of the virus in the field in South Africa. The purpose of this study was to investigate the genetic diversity of field strains of BTV in South Africa and to provide an initial assessment of the evolutionary processes shaping BTV genetic diversity in the field. Complete genomes of 35 field viruses belonging to 11 serotypes, collected from different regions of the country between 2011 and 2017, were sequenced. The sequences were phylogenetically analysed in relation to all the BTV sequences available from GenBank, including the LAVs and reference strains, resulting in the analyses and reassortment detection of 305 BTVs. Phylogenomic analysis indicated a geographical selection of the genome segments, irrespective of the serotype. Based on the initial assessment of the current genomic clades that circulate in South Africa, the selection for specific clades is prevalent in directing genome segment reassortment, which seems to exclude the vaccine strains and in multiple cases involves Segment-2 resulting in antigenic shift.Technology Innovation Agency of South Africa: E Venter Seed Fund.https://www.mdpi.com/journal/virusesVeterinary Tropical Disease

Promoting critical-analytic thinking through teacher discourse moves and pedagogical principles : the case of a rural South African secondary school

This article reports a case study in a rural South African school on promoting critical-analytic thinking through teacher discourse moves and pedagogical principles. The study investigated the use of teacher discourse moves and pedagogical principles as a component of the Quality Talk model. The Qualitative research methodology and a case study design that entailed the use of interviews, classroom observations and document analysis were used. Data was gathered from an English teacher and 52 Grade 8 students. The data was coded using Quality Talk model indicators and analysed thematically. The findings revealed evidence that teacher training and support in the use of a range of teacher discourse moves and pedagogical principles could enhance students’ development of critical-analytic thinking. It is therefore recommended that teacher training in the use of pedagogical approaches that enhance the development of critical-analytic thinking should be incorporated in professional development programmes.https://www.ajol.info//index.php/jlthj2021Educational Psycholog

Seminal transmission of lumpy skin disease virus in heifers

It is known that lumpy skin disease virus (LSDV) can be shed in bull semen following infection and that artificial insemination (AI) poses a biosecurity risk. It is however not known whether the use of LSDV infected semen in AI poses a biosecurity risk. The aims of the current study were to investigate whether LSDV, transmitted through semen, can infect cows and embryos.. Two controlled trials were performed simultaneously. Eleven (11) young beef heifers, naïve to LSDV, were synchronized using an OvSynch protocol and inseminated with fresh semen spiked with a field strain of LSDV on day 0. Six (6) of the heifers were superovulated on Day 1 using PMSG, and embryos were flushed from these heifers on Day 6. Blood and serum samples were collected from Day 4 until Day 27 to determine the presence of LSDV by PCR and virus isolation, and the presence of antibodies against LSDV by SNT. The first clinical signs of LSD were noticed on Day 10, followed by severe generalized LSD in 3 heifers, and mild LSD in 2 more heifers. Two heifers were humanely euthanized due to severe unresponsive stranguria. LSDV was detected by PCR, virus isolation or electron microscopy in blood, embryos and organs of experimentally infected animals, and 8 heifers had seroconverted by Day 27. Two control animals were not affected. This is the first report of experimental seminal transmission of LSDV in cattle.NRF. Project number FA 200704250000.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1865-16822015-10-31hb201

Culicoides species abundance and potential overwintering of African horse sickness virus in the Onderstepoort area, Gauteng, South Africa

In South Africa, outbreaks of African horse sickness (AHS) occur in summer; no cases are reported in winter, from July to September. The AHS virus (AHSV) is transmitted almost exclusively by Culicoides midges (Diptera: Ceratopogonidae), of which Culicoides imicola is considered to be the most important vector. The over-wintering mechanism of AHSV is unknown. In this study, more than 500 000 Culicoides midges belonging to at least 26 species were collected in 88 light traps at weekly intervals between July 2010 and September 2011 near horses in the Onderstepoort area of South Africa. The dominant species was C. imicola. Despite relatively low temperatures and frost, at least 17 species, including C. imicola, were collected throughout winter (June–August). Although the mean number of midges per night fell from > 50 000 (March) to < 100 (July and August), no midge-free periods were found. This study, using virus isolation on cell cultures and a reverse transcriptase polymerase chain reaction (RT-PCR) assay, confirmed low infection prevalence in field midges and that the detection of virus correlated to high numbers. Although no virus was detected during this winter period, continuous adult activity indicated that transmission can potentially occur. The absence of AHSV in the midges during winter can be ascribed to the relatively low numbers collected coupled to low infection prevalence, low virus replication rates and low virus titres in the potentially infected midges. Cases of AHS in susceptible animals are likely to start as soon as Culicoides populations reach a critical level.http://www.jsava.co.zatm201

An improved method for determining virucidal efficacy of a chemical disinfectant using an electrical impedance assay

A major problem with the testing of virucidal efficacy using current protocols is that scoring of virus-induced cytopathic effect (CPE) is dependent on subjective visual interpretation using light microscopy. The current report details the use of an electrical impedance assay (xCELLigence, ACEA Biosciences) for its utility in virucidal efficacy testing. In this study, the xCELLigence system was used in a procedure developed from guidelines given by the Deutsche Vereiniging zur Bekampfung der Viruskrankheiten (DVV) (German Association for the Control of Virus Diseases) in order to demonstrate the inactivation of infectious bursal disease virus using a commercial virucide. Although the modified DVV assay using the xCELLigence system yielded identical results (i.e. a 5-log 10 reduction in viral infectivity) as the traditional DVV assay, the system allows virucidal efficacy and cytotoxicity to be measured in a more precise and reproducible fashion