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Spatial distribution and habitat selection of culicoides imicola: The potential vector of bluetongue virus in Tunisia
2021
Thameur,Ben H. | Soufiène,Sghaier | Ammar,Heni Haj | Hammami,Salah
The increasing threat of vector-borne diseases (VBDs) represents a great challenge to those who manage public and animal health. Determining the spatial distribution of arthropod vector species is an essential step in studying the risk of transmission of a vector-borne pathogen (VBP) and in estimating risk levels of VBD. Risk maps allow better targeting surveillance and help in designing control measures. We aimed to study the geographical distribution of Culicoides imicola, the main competent vector of Bluetongue virus (BTV) in sheep in Tunisia. Fifty-three records covering the whole distribution range of C.imicola in Tunisia were obtained during a 2-year field entomological survey (August 2017 - January 2018 and August 2018 - January 2019). The ecological niche of C. imicola is described using ecological-niche factor analysis (ENFA) and Mahalanobis distances factor analysis (MADIFA). An environmental suitability map (ESM) was developed by MaxEnt software to map the optimal habitat under the current climate background. The MaxEnt model was highly accurate with a statistically significant area under curve (AUC) value of 0.941. The location of the potential distribution of C. imicola is predicted in specified regions of Tunisia. Our findings can be applied in various ways such as surveillance and control program of BTV in Tunisia.
Afficher plus [+] Moins [-]Finding of a two-headed green turtle embryo during nest monitoring in Baa Atoll, Maldives
2021
Köhnk,Stephanie | Brown,Rosie | Liddell,Amelia
Green sea turtles are one of the two species of marine turtles known to nest in the Maldives. The prevalent time of nesting seems to be inconsistent throughout the island nation. In this study, sea turtle nesting activity was monitored on the island of Coco Palm Dhuni Kolhu in Baa Atoll over a period of 12 months. A total of 13 nests were confirmed with a median hatching success rate of 89.58% as ascertained by nest excavation. In one of the nests, a severely deformed hatchling with polycephaly, an opening in the neck area and a lordotic spine was found, and we investigated in detail with radiographic images and a necropsy. Our findings support the importance of consistent nesting activity and nest monitoring efforts in the country as a basis for conservation efforts.
Afficher plus [+] Moins [-]Review of African swine fever outbreaks history in South Africa: From 1926 to 2018
2021
Mushagalusa,Ciza A. | Etter,Eric | Penrith,Mary-Louise
The article reviews the outbreaks and distribution of African swine fever (ASF) in South Africa since the first probable outbreak that occurred in the Koedoesrand Ward in 1926. Retrospective data on the ASF outbreaks in South Africa were obtained from the World Organisation for Animal Health (OIE) disease database and the South African veterinary services annual reports in addition to published articles and online sources. South Africa has experienced many outbreaks that can be divided into 2 time periods: the period before the development of the OIE diseases database (1993) and the period after. More than 141 outbreaks of ASF were reported during the first period. Since the development of OIE disease database, 72 outbreaks directly involving 2968 cases, 2187 dead and 2358 killed pigs mainly in smallholder pig farms were reported. The median number of cases for a given ASF outbreak is 17, but in 50% of outbreaks no pigs were killed for prevention. The most important ASF outbreak was reported in April 2014 in the Greater Zeerust district (North West province) involving 326 cases and 1462 killed pigs. However, the outbreak with highest mortality involving 250 pigs was reported in 2016 (Free State province). According to phylogenetic analysis, nine p72 genotypes (I, III, IV, VII, VIII, XIX, XX, XXI and XXII) have been identified in South Africa. Season-wise, more outbreaks were recorded during summer. It was also observed that the OIE disease database could contain errors that would have been introduced through compiled forms at country level. Spatiotemporal studies on ASF outbreaks in South Africa are therefore required in order to assess statistically and quantitatively the clustering of outbreaks over space and time.
Afficher plus [+] Moins [-]Surveillance of the rabies-related lyssavirus, Mokola in non-volant small mammals in South Africa
2021
McMahon,William C. | Coertse,Jessica | Kearney,Teresa | Keith,Mark | Swanepoel,Lourens H. | Markotter,Wanda
The reservoir host of Mokola virus (MOKV), a rabies-related lyssavirus species endemic to Africa, remains unknown. Only sporadic cases of MOKV have been reported since its first discovery in the late 1960s, which subsequently gave rise to various reservoir host hypotheses. One particular hypothesis focusing on non-volant small mammals (e.g. shrews, sengis and rodents) is buttressed by previous MOKV isolations from shrews (Crocidura sp.) and a single rodent (Lophuromys sikapusi). Although these cases were only once-off detections, it provided evidence of the first known lyssavirus species has an association with non-volant small mammals. To investigate further, retrospective surveillance was conducted in 575 small mammals collected from South Africa. Nucleic acid surveillance using a pan-lyssavirus quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) assay of 329 brain samples did not detect any lyssavirus ribonucleic acid (RNA). Serological surveillance using a micro-neutralisation test of 246 serum samples identified 36 serum samples that were positive for the presence of MOKV neutralising antibodies (VNAs). These serum samples were all collected from Gerbilliscus leucogaster (Bushveld gerbils) rodents from Meletse in Limpopo province (South Africa). Mokola virus infections in Limpopo province have never been reported before, and the high MOKV seropositivity of 87.80% in these gerbils may indicate a potential rodent reservoir.
Afficher plus [+] Moins [-]Corrigendum: Investigation of the acaricidal activity of the acetone and ethanol extracts of 12 South African plants against the adult ticks of Rhipicephalus turanicus
2021
Fouche,Gerda | Sakong,Bellonah M. | Adenubi,Olubukola T. | Dzoyem,Jean Paul | Naidoo,Vinny | Leboho,Tlabo | Khosa,Mbokota C. | Wellington,Kevin W. | Eloff,Jacobus N.
Corrigendum: Acaricidal activity of the aqueous and hydroethanolic extracts of 15 South African plants against Rhipicephalus turanicus and their toxicity on human liver and kidney cells
2021
Fouche,Gerda | Adenubi,Olubukola T. | Leboho,Tlabo | Khosa,Mbokota C. | McGaw,Lyndy J. | Naidoo,Vinny | Wellington,Kevin W. | Eloff,Jacobus N.
Corrigendum: Anthelmintic activity of acetone extracts from South African plants used on egg hatching of Haemonchus contortus
2021
Fouche,Gerda | Sakong,Bellonah M. | Adenubi,Olubukola T. | Pauw,Elizabeth | Leboho,Tlabo | Khosa,Mbokota C. | Wellington,Kevin W. | Eloff,Jacobus N.
Wide circulation of peste des petits ruminants virus in sheep and goats across Nigeria
2021
Mantip,Samuel E. | Sigismeau,Anthony | Nanven,Maurice | Joel,Atuman | Qasim,Abayomi M. | Musa,Sada Aliyu Ibrahim | Ezeanyika,Ogechukwu | Faramade,Ibikunle | Ahmed,Garba | Woma,Timothy Y. | Shamaki,David | Libeau,Genevieve | Farougou,Souaibou | Bataille,Arnaud
Peste des petits ruminants (PPR) is a highly contagious viral disease that mainly affects goats and sheep in Asia, Africa and the Middle East, and threatens Europe [R.E.1]. The disease is endemic on the African continent, particularly in West Africa, and is a major factor driving food insecurity in low-income populations. The aim of this research study was to carry out surveillance, genetic characterisation and isolation of recently circulating PPR viruses (PPRV) in sheep and goats from the six agro-ecological zones of Nigeria. A total of 268 post-mortem tissue samples of lung and mesenteric ganglia were collected from clinically suspected sheep and goats in 18 different states, of which five never previously sampled. The presence of PPRV was confirmed using a reverse-transcription coupled with a polymerase chain reaction (RT-PCR) assay. A total of 72 samples, 17 sheep (6%) and 55 goats (21%), were found to be PPR positive. Positive samples were distributed in almost all states, except Kano, where PPR was detected in previous studies. The PPRV-positive samples were further confirmed by sequencing or virus isolation in areas where the infection had never previously been detected. These results confirm the active circulation of PPRV across all six agro-ecological zones of Nigeria, and consequently, the need for introducing strict measures for the control and prevention of the disease in the country.
Afficher plus [+] Moins [-]Analysis of antibiotic resistance phenotypes and genes of Escherichia coli from healthy swine in Guizhou, China
2021
Yu, Bo(Yangzhou University College of Veterinary Medicine ,Guizhou Academy of Agricultural Sciences Institute of Animal Husbandry and Veterinary Medicine) | Zhang, Yanan(Guizhou Academy of Agricultural Sciences Institute of Animal Husbandry and Veterinary Medicine) | Yang, Li(Guizhou Academy of Agricultural Sciences Institute of Animal Husbandry and Veterinary Medicine) | Xu, Jinge(Guizhou Academy of Agricultural Sciences Institute of Animal Husbandry and Veterinary Medicine) | Bu, Shijin(Yangzhou University College of Veterinary Medicine)
This study was carried out to investigate the resistance phenotypes and resistance genes of Escherichia coli from swine in Guizhou, China. A total of 47 E. coli strains isolated between 2013 and 2018 were tested using the Kirby-Bauer (K-B) method to verify their resistance to 19 common clinical antimicrobials. Five classes consisting of 29 resistance genes were detected using polymerase chain reaction. The status regarding extended-spectrum β-lactamase (ESBL) and the relationship between ESBL CTX-M-type β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) genes were analysed. A total of 46 strains (97.9%) were found to be multidrug resistant. Amongst them, 27 strains (57.4%) were resistant to more than eight antimicrobials, and the maximum number of resistant antimicrobial agents was 16. Twenty antibiotic resistance genes were detected, including six β-lactamase genes blaTEM (74.5%), blaCTX-M-9G (29.8%), blaDHA (17.0%), blaCTX-M-1G (10.6%), blaSHV (8.5%), blaOXA (2.1%), five aminoglycoside-modifying enzyme genes aac(3′)-IV (93.6%), aadA1 (78.7%), aadA2 (76.6%), aac(3′)-II c (55.3%), aac(6′)-Ib (2.1%) and five amphenicol resistance genes floR (70.2%), cmlA (53.2%), cat2 (10.6%), cat1 (6.4%), cmlB (2.1%), three PMQR genes qnrS (55.3%), oqxA (53.2%), qepA (27.7%) and polypeptide resistance gene mcr-1 (40.4%). The detection rate of ESBL-positive strains was 80.9% (38/47) and ESBL TEM-type was the most abundant ESBLs. The percentage of the PMQR gene in blaCTX-M-positive strains was high, and the detection rate of blaCTX-M-9G was the highest in CTX-M type. It is clear that multiple drug resistant E. coli is common in healthy swine in this study. Extended-spectrum β-lactamase is very abundant in the E. coli strains isolated from swine and most of them are multiple compound genotypes.
Afficher plus [+] Moins [-]The history of the emergence and transmission of human coronaviruses
2021
Mulabbi, Elijah N.(Makerere University Faculty of Veterinary Medicine, Animal Resources and Biosecurity Department of Veterinary Medicine) | Tweyongyere, Robert(Makerere University Faculty of Veterinary Medicine, Animal Resources and Biosecurity Department of Veterinary Medicine) | Byarugaba, Denis K.(Makerere University Faculty of Veterinary Medicine, Animal Resources and Biosecurity Department of Veterinary Medicine)
Human coronaviruses are known respiratory pathogens associated with a range of respiratory illnesses, and there are considerable morbidity and hospitalisation amongst immune-compromised individuals of all age groups. The emergence of a highly pathogenic human coronavirus in China in 2019 has confirmed the long-held opinion that these viruses are important emerging and re-emerging pathogens. In this review article, we trace the discovery and emergence of coronaviruses (CoVs) over time since they were first reported. The review article will enrich our understanding on the host range, diversity and evolution, transmission of human CoVs and the threat posed by these viruses circulating in animal populations but overtime have spilled over to humans because of the increased proximity between humans and animals.
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