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Background Dengue is the world’s most prevalent mosquito-borne viral disease. It is endemic in many tropical and subtropical countries and represents a significant global health burden. The first reports of dengue virus (DENV) circulation in the South West Indian Ocean (SWIO) islands date back to the early 1940s; however, an increase in DENV circulation has been reported in the SWIO in recent years. The aim of this review is to trace the history of DENV in the SWIO islands using available records from the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We focus in particular on the most extensive data from Reunion Island, highlighting factors that may explain the observed increasing incidence, and the potential shift from one-off outbreaks to endemic dengue transmission. Methods Following the PRISMA guidelines, the literature review focused queried different databases using the keywords “dengue” or “Aedes albopictus” combined with each of the following SWIO islands the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We also compiled case report data for dengue in Mayotte and Reunion in collaboration with the regional public health agencies in these French territories. References and data were discarded when original sources were not identified. We examined reports of climatic, anthropogenic, and mosquito-related factors that may influence the maintenance of dengue transmission independently of case importation linked to travel. Findings and conclusions The first report of dengue circulation in the SWIO was documented in 1943 in the Comoros. Then not until an outbreak in 1976 to 1977 that affected approximately 80% of the population of the Seychelles. DENV was also reported in 1977 to 1978 in Reunion with an estimate of nearly 30% of the population infected. In the following 40-year period, DENV circulation was qualified as interepidemic with sporadic cases. However, in recent years, the region has experienced uninterrupted DENV transmission at elevated incidence. Since 2017, Reunion witnessed the cocirculation of 3 serotypes (DENV-1, DENV-2 and DENV-3) and an increased number of cases with severe forms and deaths. Reinforced molecular and serological identification of DENV serotypes and genotypes circulating in the SWIO as well as vector control strategies is necessary to protect exposed human populations and limit the spread of dengue.

RESUMO Objetivou-se com este trabalho otimizar a produção de enzimas celulolíticas por hps C. gloeosporioideshps URM 7080 isolado de lesões foliares de Manihot esculenta, sintomáticas de Antracnose. Utilizou-se farelo de entrecasca de mandioca (MA) e palma forrageira triturada (PA) como substratos para fermentação submersa nas concentrações 0,5, 0,75 e 1%, pH inicial 5,0, 6,0 e 7,0; agitações 80, 110 e 140 rpm e temperaturas de 28, 32 e 36 °C em experimento fatorial fracionário 25 com 32 ensaios + 4 repetições no ponto central. Os melhores parâmetros para produção de cada enzima isolada foram: 1% de MA, 0,5% de PA, 28° C, com o pH inicial 5,0 para FPAse (Celulase total) e pH 7,0 para CMCase (Endoglucanase); Para βG (β-glucosidase), pH inicial 5,0 à 36° C, e concentração de 0,5 de PA e agitação de 140 rpm para as três enzimas em conjunto. ABSTRACT The aim of the present study was to optimize the production of cellulolytic enzymes by C. gloeosporioides URM 7080 isolated from leaf lesions in Manihot esculenta showing symptoms of anthracnose. Cassava bran (MA) and crushed forage cactus (PA) were used as substrates for submerged fermentation at the concentrations of 0.5%, 0.75% and 1%; initial pH of 5.0, 6.0 and 7.0; agitation at 80, 110 and 140 rpm, and temperatures of 28, 32 and 36°C, in a 25 fractional factorial experiment with 32 trials + 4 replicates at the central point. The best parameters for the production of each isolated enzyme were: 1% MA, 0.5% PA, 28°C, and initial pH of 5.0 for FPase (total cellulase) and pH of 7.0 for CMCase (endoglucanase); initial pH of 5.0 at 36°C for βG (β-glucosidase), and concentration of 0.5% PA at 140 rpm for the three enzymes together.

RESUMO A meleira do mamoeiro é considerada um dos maiores problemas fitossanitários da cultura do mamoeiro, mas diversos aspectos da sua epidemiologia ainda são desconhecidos. O objetivo deste trabalho foi determinar o risco e o padrão espaço-temporal da meleira nas condições de cultivo da região extremo sul do estado da Bahia. Foi utilizada a regressão logística para identificar os fatores de riscos associados à ocorrência da meleira na região do extremo sul da Bahia. Para o estudo da distribuição espacial, foram aplicadas as seguintes análises: sequências ordinárias; teste t (student) e áreas isópatas. Os resultados da regressão logística mostraram que o risco de um pomar apresentar meleira sendo consorciado ou consorciado com a cultura do café é maior do que quando estes fatores estão ausentes. Em geral, a meleira evoluiu lentamente do primeiro até o sexto mês de avaliação, com média de até 17,2% de plantas infectadas no sexto mês e chegando até 88% das plantas infectadas em campo ao final da epidemia. Agregação de plantas doentes foi observada em menos da metade das áreas avaliadas. A análise de áreas isópatas indicou uma tendência para início das epidemias a partir das bordas dos pomares e a presença de focos secundários e isolados da doença. ABSTRACT Papaya meleira is considered one of the major phytosanitary problems affecting papaya culture, but several aspects of its epidemiology are still unknown. The objective of this study was to determine the risk and the spatiotemporal pattern of meleira under the cultivation conditions in the far south region of Bahia State, Brazil. Logistic regression was used to identify the risk factors associated with the occurrence of meleira in the far south region of Bahia. For the spatial distribution study, the following analyses were applied: ordinary sequences; t-test (student’s) and isopath areas. The logistic regression results evidenced that the risk that an intercropped orchard, or intercropped with the coffee crop, can show meleira is greater than that in the absence of these factors. In general, meleira evolved slowly from the first to the sixth month of evaluation, showing an average of up to 17.2% infected plants in the sixth month and reaching up to 88% infected plants in the field at the end of the epidemic. Aggregation of diseased plants was observed in less than half of the evaluated areas. Analysis of isopath areas indicated a tendency for the epidemics to start from the edges of orchards and the presence of secondary and isolated foci of the disease.

High populations of African cassava whitefly (Bemisia tabaci) have been associated with epidemics of two viral diseases in Eastern Africa. We investigated population dynamics and genetic patterns by comparing whiteflies collected on cassava in 1997, during the first whitefly upsurges in Uganda, with collections made in 2017 from the same locations. Nuclear markers and mtCOI barcoding sequences were used on 662 samples. The composition of the SSA1 population changed significantly over the 20-year period with the SSA1-SG2 percentage increasing from 0.9 to 48.6%. SSA1-SG1 and SSA1-SG2 clearly interbreed, confirming that they are a single biological species called SSA1. The whitefly species composition changed: in 1997, SSA1, SSA2 and B. afer were present; in 2017, no SSA2 was found. These data and those of other publications do not support the ‘invader’ hypothesis. Our evidence shows that no new species or new population were found in 20 years, instead, the distribution of already present genetic clusters composing SSA1 species have changed over time and that this may be in response to several factors including the introduction of new cassava varieties or climate changes. The practical implications are that cassava genotypes possessing both whitefly and disease resistances are needed urgently.

Cacao swollen shoot virus (CSSV) is causing the major viral disease on cacao (Theobroma cacao) and it is naturally transmitted by mealybugs species. CSSV is restricted to West Africa and is a serious constraint to cacao production, particularly in Ghana. From the high molecular variability of the virus, a complex of 8 viral species has been recognized and the geographical repartition of these species has been done in Côte d'Ivoire, Ghana and Togo. Measures to control the disease are discussed.

International audience

Recent viral zoonotic epidemics have been attributed partially to the negative impact of human activities on ecosystem biodiversity. Agricultural activities, particularly conventional crop protection (CP) practices, are a major threat to global biodiversity, ecosystem health and human health. Here we review interactions between CP practices and viral zoonoses (VZs), the first time this has been done. It should be noted that a) VZs stand at the interface between human, animal and ecosystem health; b) some VZs involve arthropod vectors that are affected by CP practices; and c) some crop pests, or their natural enemies are vertebrate reservoirs/carriers of certain VZs, and their contact with humans or domestic animals is affected by CP practices. Our review encompasses examples highlighting interactions between VZs and CP practices, both efficiency improvement-based (i.e. conventional with agrochemical insecticides and rodenticides), substitution-based (i.e. mainly with physical/mechanical or biopesticidal pest control), and redesign-based (i.e. mainly with conservation biological pest control, including some forms of crop-livestock integration). These CP practices mainly target arthropod and vertebrate pests. They also target, to a lesser extent, weeds and plant pathogens. Conventional and some physical/mechanical control methods and some forms of biopesticidal and crop-livestock integration practices were found to have mixed outcomes in terms of VZ risk management. Conversely, practices based on biological control by habitat conservation of arthropod or vertebrate natural enemies, falling within the Agroecological Crop Protection (ACP) framework, result in VZ prevention at various scales (local to global, and short-term to long-term). ACP addresses major global challenges including climate resilience, biodiversity conservation and animal welfare, and helps integrate plant health within the extended “One Health” concept.

New peanut lines selected from the breeding programs hould also be planted in large plots next to grower´s fields. Nine peanut breeding lines and cultivars were evaluated in Tupã, SP, during the 2019/2020 growing season in an experiment comprising three planting dates in large plots of six rows of ten meters. Cultivation management was as the indicated for the peanut crop in São Paulo. Plots of the second and third planting dates were infested by vírus, with symptoms characteristic of GRSV (Groundnut Ringspot Virus). Each of these plots was then evaluated for the number of plants with vírus symptoms. Yield data showed the highest values in the first planting, and a decrease in the second and third planting date. Among all genotypes tested, line 11.20 showed the highest yield especially at the first planting date. Line 10.677 showed a good yield stability and the highest average yield over the three planting dates. This line also presented the lowest number of vírus infested plants, indicating a potential for vírus resistance. Nuevas líneas de maní destacadas del programa de mejoramiento deben pasar por cultivos experimentales en parcelas largas junto a campos comerciales. Nueve líneas y cultivares de maní fueron evaluados em el período 2019/20 mediante um experimento instalado em tres épocas de siembra em parcelas de seis surcos de diez metros de longitude. El manejo del cultivo fue igual a um campo convencional de maní. En las parcelas instaladas la segunda y terceira época ocurrió uma infestación por tospovirus GRSV, por esse motivo fueran evaluadas el número de plantas com sintomas. Los datos mostraron los mayores rendimentos en la primera época de siembra, disminuyendo em la segunda y terceira épocas. Entre los genótipos evaluados, la línea 11.20 evidenció un alto potencial productivo, especialmente en la primera época. La línea 10.677 presentó mayor estabilidade productiva y el máximo rendimento promedio de las tres épocas. Esta línea tuvo también el menor número de plantas infestadas por vírus, presentando potencial de resistência a la enfermedad. Novas linhagens destacadas do programa de melhoramento de amendoim devem passar por cultivos experimentais em parcelas amplas junto a campos de produtores. Nove linhagens e cultivares de amendoim foram avaliados no município de Tupã, SP, na safra 2019/2020, em um experimento em campo, semeados em três épocas durante o ciclo de cultivo, em parcelões de seis linhas de dez metros. O manejo de cultivo foi o utilizado regularmente para a cultura de amendoim. Nas parcelas semeadas na segunda e terceira épocas, ocorreu infestação por vírus, caracterizado como o tospovirus GRSV, tendo assim, cada parcela sido avaliada quanto ao número de plantas com sintomas da virose. Os dados obtidos mostraram as maiores produtividades na primeira época de semeadura, decrescendo na segunda e na terceira época. Entre os genótipos avaliados, a linhagem 11.20 obteve alto potencial produtivo, especialmente na primeira época de semeadura. A linhagem 10.677 apresentou maior estabilidade produtiva, a maior produtividade na média das três épocas de plantio, além do menor número de plantas infestadas com vírus, indicando potencial de resistência à doença.

An outbreak of banana streak virus (BSV) was observed in Santa Catarina, Brazil, in the counties of Luís Alves, Massaranduba and Corupá in cultivars of the subgroup Cavendish (Grand Naine and Nanicão) in the2009/10 crop season. BSV causes yellow or chlorotic leaf streaks leading to leaf death. Dark necrotic streaks are observed in the main vein of leaves on the petiole and on the leaf sheath. Tissues inside the pseudostem are destroyed due to infection by the virus, and during the flowering there is “choking” of the pseudostem in the rosette-like leaveswhich prevent normal emergence of the bunch. This causes “abortion” in different points bolow the rosette. Infected plants produce smaller and distorted (inverted) bunches, as well as illformed and necrotic fruits, which eventually split. Eliminating contaminated plants, controlling mealybugs and using healthy plantlets are measures that contributeto the control of BSV. No ano agrícola 2009/10, foi constatada em Santa Catarina, nos municípios de Luís Alves, Massaranduba e Corupá, a ocorrência de “banana streak virus” (BSV) nas cultivares de banana Grande Naine e Nanicão, do subgrupoCavendish. O BSV produz estrias amarelas ou cloróticas nas folhas, que escurecem com o tempo, evoluindo até a morte do tecido. Na bainha, no pecíolo e na nervura principal das folhas ocorrem estrias necróticas escuras. Nointerior do pseudocaule o vírus provoca destruição dos tecidos, e na floração ocorre estrangulamento do pseudocaule na região da roseta foliar, que impede a emergência normal do cacho, provocando “aborto” em diferentes pontosabaixo da roseta. As bananeiras infectad as produzem cachos menores podendo apresentar o engaço retorcido, frutos malformados e manchados. Sob as manchas escuras da epiderme dos frutos, o tecido da casca apresenta-se necrosado, vindo a rachar. A eliminação das plantas contaminadas, o controle de cochonilhas e a utilização de mudas sadias contribuem para o controle da doença.

Capripoxviruses (CaPVs) have been shown to be ideal viral vectors for the development of recombinant multivalent vaccines to enable delivery of immunogenic genes from ruminant pathogens. So far, the viral thymidine kinase (TK) gene is the only gene used to generate recombinants. A putative non-essential gene encoding a G-protein-coupled chemokine receptor subfamily homologue (GPCR) was targeted as an additional insertion site. Peste des petits ruminants (PPR) was chosen as a disease model. A new recombinant CaPV expressing the viral attachment hemagglutinin (H) of the PPR virus (PPRV) in the GPCR insertion site (rKS1-HPPR-GPCR) was generated in the backbone North African isolate KS1 strain of lumpy skin disease virus (LSDV). Comparison with the recombinant CaPV expressing the H of PPRV in the TK gene (rKS1-HPPR-TK) shown to induce protection against both PPR and LSD in both sheep and goats was assessed. The suitability of the GPCR gene to be a putative additional insertion site in the CaPV genome is evaluated and discussed.

International audience; Peste des Petits Ruminants (PPR) is a viral disease affecting predominantly small ruminants. Due to its transboundary nature, regional coordination of control strategies will be key to the success of the on-going PPR eradication campaign. Here, we aimed at exploring the extent of transboundary movement of PPR in West Africa using phylogenetic analyses based on partial viral gene sequences. We collected samples and obtained partial nucleoprotein gene sequence from PPR-infected small ruminants across countries within West and Central Africa. This new sequence data was combined with publically available data from the region to perform phylogenetic analyses. A total of fifty-five sequences were obtained in a region still poorly sampled. Phylogenetic analyses showed that the majority of virus sequences obtained in this study were placed within genetic clusters regrouping samples from multiple West African and Central African countries. Some of these clusters contained samples from countries sharing borders. In other cases, clusters grouped samples from very distant countries. Our results suggest extensive and recurrent transboundary movements of PPR within West Africa, supporting the need for a regional coordinated strategy for PPR surveillance and control in the region. Simple phylogenetic analyses based on readily available data can provide information on PPR transboundary dynamics and, therefore, could contribute to improve control strategies. On-going and future projects dedicated to PPR should include extensive genetic characterization and phylogenetic analyses of circulating viral strains in their effort to support the campaign for global eradication of the disease.

his book primarily focuses on the African Sahel region, shedding new light on the epidemiology, socio-economics, clinical manifestations and control approaches of transboundary animal diseases (TADs) in this specific region. In addition to the description of TADs in Sahelian Africa and connected regions, several issues regarding the burden of TADs, the role of national/regional/international veterinary organizations in the surveillance process, animal mobility, one health and TADs in the dromedary are discussed. The book contains 22 chapters and is structured in three parts, i- general features and commonalities, ii- viral diseases, iii- bacterial diseases. Each chapter was written by a group of experts specialized in the topic. This work will be of general interest to researchers, veterinarians, veterinary public health officers, and students engaged in the surveillance and control of animal infectious diseases, included those of zoonotic nature and that are prevalent in the Sahel.

Objective To establish a surveillance in Dong Thap, at the border with Cambodia by assessing the presence of DENV serotypes and CHIKV among patients hospitalized at Dong Thap general hospital. Methods Cross-sectional descriptive analysis was conducted on a cohort of 131 patients hospitalized with acute fever and symptoms compatible with dengue or chikungunya. The study was conducted from January 2012 to February 2013. The full clinical picture was established as well as serological and molecular detection. Serological analysis was sequentially performed on blood samples collected on admission and an average of seven days after admission. The detection of IgM antibody to DENV was performed by IgM capture ELISA and the detection of DENV and CHIKV RNA was done by reverse-transcription multiplex PCR. Results 101 patients out of 131 (77%) were confirmed with dengue. All four dengue serotypes were detected with a predominance of DENV2 and DENV4. No chikungunya infection was detected although reported in neighboring Cambodia. A differential efficiency of serological dengue detection was observed. Efficiency was 29% upon admission and 53% after seven days on the same patients. 30 patients out of 131 (23%) were negative with both DENV and CHIKV. Conclusions Dengue is at risk of being underestimated and chikungunya is not systematically detected. Changes in detection and surveillance procedures are therefore discussed to increase efficiency of dengue detection and continue the monitoring the emergence of CHIKV in Dong Thap province and in Vietnam.

After its introduction in Turkey in November 2013 and subsequent spread in this country, lumpy skin disease (LSD) was first reported in the western Turkey in May 2015. It was observed in cattle in Greece and reported to the World Organization for Animal Health (OIE) in August 2015. From May 2015 to August 2016, 1,092 outbreaks of lumpy skin disease were reported in cattle from western Turkey and eight Balkan countries: Greece, Bulgaria, The Former Yugoslav Republic of Macedonia, Serbia, Kosovo, and Albania. During this period, the median LSD spread rate was 7.3 km/week. The frequency of outbreaks was highly seasonal, with little or no transmission reported during the winter. Also, the skewed distribution of spread rates suggested two distinct underlying epidemiological processes, associating local and distant spread possibly related to vectors and cattle trade movements, respectively. (Resume d'auteur)

Bats carry a great diversity of zoonotic viruses with a high-impact on human health and livestock. Since the emergence of new coronaviruses and paramyxoviruses in humans (e.g. Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Nipah virus), numerous studies clearly established that bats can maintain some of these viruses. Improving our understanding on the role of bats in the epidemiology of the pathogens they harbour is necessary to prevent cross-species spill over along the wild/domestic/human gradient. In this study, we screened bat faecal samples for the presence of Coronavirus and Paramyxovirus in two caves frequently visited by local people to collect manure and/or to hunt bats in Zimbabwe. We amplified partial RNA-dependent RNA polymerase genes of Alpha and Betacoronavirus together with the partial polymerase gene of Paramyxovirus. Identified coronaviruses were related to pathogenic human strains and the paramyxovirus belonged to the recently described Jeilongvirus genus. Our results highlighted the importance of monitoring virus circulation in wildlife, especially bats, in the context of intense human-wildlife interfaces in order to strengthen prevention measures among local populations and to implement sentinel surveillance in sites with high zoonotic diseases transmission potential., Highlights • Coronavirus and Paramyxovirus circulate in Hipposideros bat species in Zimbabwe. • Importance of widening viral screening in under-investigated countries • Sentinel surveillance in sites with high zoonotic transmission potential

A Língua Azul ou Febre Catarral Ovina é uma doença viral transmitida por artrópodes, nomeadamente mosquitos do género Culicoides, que afeta ruminantes com maior ou menor virulência, dependendo de diversos fatores (Kyriakis, et al., 2015; Spedicato, 2016). A Língua Azul foi reconhecida há mais de 100 anos na África do Sul, sendo considerada enzoótica em todas as regiões tropicais e temperadas do mundo, no entanto, têm sido descritas alterações regionais drásticas recentes na distribuição global do vírus de Língua Azul, sobretudo na Europa, desde 1998 (Maclachlan, 2011). Assim, no presente trabalho são apresentados os resultados de um estudo sobre a monitorização de anticorpos IgG contra o vírus de Língua Azul em Ovelhas Serra da Estrela, em quatro concelhos da Beira Interior: Celorico da Beira, Fornos de Algodres, Seia e Gouveia, em Fevereiro e Junho de 2016. Para tal, foram visitadas 56 explorações, num total de 105 amostras de leite do tanque e ainda 27 explorações, para recolha de um total de 204 amostras de sangue por punção da veia jugular, por centrifugação foi obtido o lacto-soro e o soro. Posteriormente, foi aplicado um teste de ELISA, com recurso a dois kits comerciais ID Screen® BlueTongue Milk Indirect e ID Screen® BlueTongue Competition para a deteção de anticorpos contra a proteína VP7 do vírus de Língua Azul. Nos resultados obtidos, constatou-se, um aumento da prevalência de anticorpos IgG contra o vírus de Língua Azul, relativamente às amostras de leite do primeiro momento, para o segundo momento de 91,07% para 93,88%, respetivamente, o que pode sugerir a emergência do vírus. E registou-se ainda, no que se refere às amostras de sangue uma diminuição da seroprevalência de 4,63% para 3,13%, respetivamente em Fevereiro e Junho de 2016, o que pode sugerir uma diminuição do alcance do vetor. ABSTRACT: The BlueTongue or Catarrhal Fever Ovine is a viral disease transmitted by arthropods, namely midges of the genus Culicoides, which affects ruminants with greater or lesser virulence depending on several factors (Kyriakis, et al., 2015; Spedicato, 2016). The BlueTongue has been recognized has more than 100 years in South Africa and is considered enzootic in all the tropical and temperate regions of the world, however, recent drastic regional changes have been described in the global distribution of Bluetongue virus, especially in Europe, since 1998 (Maclachlan, 2011). Therefore, in this work, are presented the results of a study about monitoring of IgG antibodies against Bluetongue virus in Ovinos Serra da Estrela in four municipalities of Beira Interior: Celorico da Beira, Fornos de Algodres, Seia e Gouveia, in February and June of 2016. For this purpose, 56 farms were visited, in a total of 105 milk samples from the tank and 27 farms, to collect a total of 204 samples of blood by puncture of the jugular vein, by centrifugation the lacto-serum and the serum were obtained. Posteriorly, an ELISA test was applied using two commercial ID Screen® BlueTongue Milk Indirect and ID Screen® BlueTongue Competition kits for the detection of antibodies against the BlueTongue virus VP7 protein. In the obtained results, an increase in the prevalence of IgG antibodies against the BlueTongue virus was detected in relation to the milk samples from the first moment, for the second moment of 91.07% and 93.88%, respectively. May suggest the emergence of the virus. And a decrease in seroprevalence from 4.63% to 3.13% was recorded for blood samples, respectively in February and June 2016, which may suggest a decrease in the vector range.