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Giammarioli M, Torresi C, Biccheri R, Cammà C, Marcacci M, Dondo A, Razzuoli E, Fusco G, Casalinuovo F, Scicluna MT, Dei Giudici S, Martin AMM, Rossi E, Casciari C, Pela M, Iscaro C, Gallardo C, Marocco G, Orrico M, Feliziani F. Genetic Characterization of African Swine Fever Italian Clusters in the 2022-2023 Epidemic Wave by a Multi-Gene Approach. Viruses 2024; 16:1185. [PMID: 39205159 PMCID: PMC11360507 DOI: 10.3390/v16081185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Revised: 07/18/2024] [Accepted: 07/19/2024] [Indexed: 09/04/2024] Open
Abstract
The first report of African swine fever virus (ASFV) genotype II in Italy in 2022 marked the beginning of a significant invasion in at least eight Italian regions with different infection clusters. In this study, we used the multi-gene approach to investigate the epidemiological associations between ASFV strains causing cases and outbreaks in wild boar and pigs in Italy from January 2022 to the end of 2023. Our results confirm that all the tested ASFV-positive Italian samples belonged to genotype II and show high homology with genotype II ASFV sequences previously collected in Eurasian countries. Molecular characterization revealed the presence of four genetic groups in Italy. The majority of African swine fever (ASF) samples analyzed in the current study (72%) belonged to genetic group 3, which was the most representative in Europe. The results also provide evidence of the prevalence of genetic group 19 (15.9%). In addition, we identified new putative genetic groups, genetic group 25 (9.1%) and genetic group 26 (3.0%), which have never been described before. This is the first detailed report on the molecular characterization of more than 130 ASFV strains circulating in Italy.
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Affiliation(s)
- Monica Giammarioli
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Claudia Torresi
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Roberta Biccheri
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Cesare Cammà
- National Reference Center for Whole Genome Sequencing of Microbial Pathogens, Database and Bioinformatic Analysis, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”, 64100 Teramo, Italy; (C.C.); (M.M.)
| | - Maurilia Marcacci
- National Reference Center for Whole Genome Sequencing of Microbial Pathogens, Database and Bioinformatic Analysis, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”, 64100 Teramo, Italy; (C.C.); (M.M.)
| | - Alessandro Dondo
- Istituto Zooprofilattico Sperimentale Piemonte, Liguria e Valle d’Aosta “I. Altara”, 10154 Turin, Italy; (A.D.); (E.R.)
| | - Elisabetta Razzuoli
- Istituto Zooprofilattico Sperimentale Piemonte, Liguria e Valle d’Aosta “I. Altara”, 10154 Turin, Italy; (A.D.); (E.R.)
| | - Giovanna Fusco
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Portici, 80055 Napoli, Italy; (G.F.); (F.C.)
| | - Francesco Casalinuovo
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Portici, 80055 Napoli, Italy; (G.F.); (F.C.)
| | - Maria Teresa Scicluna
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana “M. Aleandri”, 00178 Rome, Italy;
| | - Silvia Dei Giudici
- Istituto Zooprofilattico Sperimentale della Sardegna “G. Pegreffi”, 07100 Sassari, Italy;
| | - Ana Maria Moreno Martin
- Istituto Zooprofilattico Sperimentale della Lombardia e della Emilia Romagna “Bruno Ubertini”, 25124 Brescia, Italy;
| | - Elisabetta Rossi
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Cristina Casciari
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Michela Pela
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Carmen Iscaro
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | - Carmina Gallardo
- European Union Reference Laboratory for African Swine Fever (EURL), Centro de Investigación en Sanidad Animal (CISA), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Consejo Superior de Investigaciones Científicas (CSIC), Valdeolmos, 28130 Madrid, Spain;
| | - Gaia Marocco
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
| | | | - Francesco Feliziani
- National Reference Laboratory (NRL) for Swine Fever, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati”, 06126 Perugia, Italy; (C.T.); (R.B.); (E.R.); (C.C.); (M.P.); (C.I.); (G.M.); (F.F.)
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Ramirez-Medina E, Rai A, Espinoza N, Spinard E, Silva E, Burton L, Clark J, Meyers A, Valladares A, Velazquez-Salinas L, Gay CG, Gladue DP, Borca MV. Recombinant Vaccine Strain ASFV-G-Δ9GL/ΔUK Produced in the IPKM Cell Line Is Genetically Stable and Efficacious in Inducing Protection in Pigs Challenged with the Virulent African Swine Fever Virus Field Isolate Georgia 2010. Pathogens 2024; 13:319. [PMID: 38668274 PMCID: PMC11055038 DOI: 10.3390/pathogens13040319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/10/2024] [Accepted: 04/11/2024] [Indexed: 04/29/2024] Open
Abstract
We have previously reported that the recombinant African Swine Fever (ASF) vaccine candidate ASFV-G-Δ9GL/ΔUK efficiently induces protection in domestic pigs challenged with the virulent strain Georgia 2010 (ASFV-G). As reported, ASFV-G-Δ9GL/ΔUK induces protection, while intramuscularly (IM), administered at doses of 104 HAD50 or higher, prevents ASF clinical disease in animals infected with the homologous ASFV g strain. Like other recombinant vaccine candidates obtained from ASFV field isolates, ASFV-G-Δ9GL/ΔUK stocks need to be produced in primary cultures of swine macrophages, which constitutes an important limitation in the production of large virus stocks at the industrial level. Here, we describe the development of ASFV-G-Δ9GL/ΔUK stocks using IPKM (Immortalized Porcine Kidney Macrophage) cells, which are derived from swine macrophages. We show that ten successive passages of ASFV-G-Δ9GL/ΔUK in IPKM cells induced small changes in the virus genome. The produced virus, ASFV-G-Δ9GL/ΔUKp10, presented a similar level of replication in swine macrophages cultures to that of the original ASFV-G-Δ9GL/ΔUK (ASFV-G-Δ9GL/ΔUKp0). The protective efficacy of ASFV-G-Δ9GL/ΔUKp10 was evaluated in pigs that were IM-inoculated with either 104 or 106 HAD50 of ASFV-G-Δ9GL/ΔUKp10. While animals inoculated with 104 HAD50 present a partial protection against the experimental infection with the virulent parental virus ASFV-G, those inoculated with 106 HAD50 were completely protected. Therefore, as was just recently reported for another ASF vaccine candidate, ASFV-G-ΔI177L, IPKM cells are an effective alternative to produce stocks for vaccine strains which only grow in swine macrophages.
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Affiliation(s)
- Elizabeth Ramirez-Medina
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Ayushi Rai
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Edward Spinard
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Ediane Silva
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Leeanna Burton
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Jason Clark
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Amanda Meyers
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Alyssa Valladares
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Lauro Velazquez-Salinas
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Cyril G. Gay
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA;
| | - Douglas P. Gladue
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Manuel V. Borca
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.R.-M.); (A.R.); (N.E.); (E.S.); (A.M.); (A.V.); (L.V.-S.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
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Pakotiprapha D, Kuhaudomlarp S, Tinikul R, Chanarat S. Bridging the Gap: Can COVID-19 Research Help Combat African Swine Fever? Viruses 2023; 15:1925. [PMID: 37766331 PMCID: PMC10536364 DOI: 10.3390/v15091925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
African swine fever (ASF) is a highly contagious and economically devastating disease affecting domestic pigs and wild boar, caused by African swine fever virus (ASFV). Despite being harmless to humans, ASF poses significant challenges to the swine industry, due to sudden losses and trade restrictions. The ongoing COVID-19 pandemic has spurred an unparalleled global research effort, yielding remarkable advancements across scientific disciplines. In this review, we explore the potential technological spillover from COVID-19 research into ASF. Specifically, we assess the applicability of the diagnostic tools, vaccine development strategies, and biosecurity measures developed for COVID-19 for combating ASF. Additionally, we discuss the lessons learned from the pandemic in terms of surveillance systems and their implications for managing ASF. By bridging the gap between COVID-19 and ASF research, we highlight the potential for interdisciplinary collaboration and technological spillovers in the battle against ASF.
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Affiliation(s)
| | | | | | - Sittinan Chanarat
- Department of Biochemistry and Center for Excellence in Protein and Enzyme Technology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
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An Updated Review of Ornithodoros Ticks as Reservoirs of African Swine Fever in Sub-Saharan Africa and Madagascar. Pathogens 2023; 12:pathogens12030469. [PMID: 36986391 PMCID: PMC10059854 DOI: 10.3390/pathogens12030469] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/19/2023] Open
Abstract
This updated review provides an overview of the available information on Ornithodoros ticks as reservoirs and biological vectors of the ASF virus in Africa and Indian Ocean islands in order to update the current knowledge in this field, inclusive of an overview of available methods to investigate the presence of ticks in the natural environment and in domestic pig premises. In addition, it highlights the major areas of research that require attention in order to guide future investigations and fill knowledge gaps. The available information suggests that current knowledge is clearly insufficient to develop risk-based control and prevention strategies, which should be based on a sound understanding of genotype distribution and the potential for spillover from the source population. Studies on tick biology in the natural and domestic cycle, including genetics and systematics, represent another important knowledge gap. Considering the rapidly changing dynamics affecting the African continent (demographic growth, agricultural expansion, habitat transformation), anthropogenic factors influencing tick population distribution and ASF virus (ASFV) evolution in Africa are anticipated and have been recorded in southern Africa. This dynamic context, together with the current global trends of ASFV dissemination, highlights the need to prioritize further investigation on the acarological aspects linked with ASF ecology and evolution.
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Masembe C, Adedeji AJ, Jambol AR, Weka R, Muwanika V, Luka PD. Diversity and emergence of new variants of African swine fever virus Genotype I circulating in domestic pigs in Nigeria (2016-2018). Vet Med Sci 2023; 9:819-828. [PMID: 36377750 PMCID: PMC10152979 DOI: 10.1002/vms3.988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND African swine fever (ASF) is the most lethal disease of pigs caused by ASF virus (ASFV) with severe economic implications and threat to the swine industry in endemic countries. Between 2016 and 2018, several ASF outbreaks were reported throughout pig producing states in Nigeria. OBJECTIVES Thereafter, this study was designed to identify the ASFV genotypes responsible for these outbreaks within the study period (2016-2018). METHODS Twenty-two ASFV-positive samples by polymerase chain reaction were selected. The samples were collected during passive surveillance in eight states of Nigeria were characterised using 3 partial genes sequences of the virus namely, p72 capsid protein of the B646L, p54 envelope protein of E183L and the central variable region (CVR) within B602L of ASFV. RESULTS Phylogenetic and sequences analysis based on p72 and p54 revealed ASFV genotype I as the circulating virus. Sequence analysis of the CVR of B602L revealed genetic variations with six ASFV tandem repeat sequence (TRS) variants namely, Tet-15, Tet-20a, Tet-21b, Tet-27, Tet-31 and Tet-34, thus increasing the overall genetic diversity of ASFV in Nigeria. Three of the TRS variants, Tet-21b, Tet-31 and Tet-34, were identified for the first time in Nigeria. The new TRS variants of ASFV genotype I were identified in Enugu, Imo, Plateau and Taraba states, while co-circulation of multiple variants of ASFV genotype I was recorded in Plateau and Benue states. CONCLUSIONS The high genetic diversity, emergence and increasing recovery of new variants of genotype I in Nigeria should be a concern given that ASFV is a relatively stable DNA virus. The epidemiological implications of these findings require further investigation.
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Affiliation(s)
- C Masembe
- College of Natural Sciences, Makerere University, Kampala, Uganda
| | - A J Adedeji
- College of Natural Sciences, Makerere University, Kampala, Uganda
- Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria
| | - A R Jambol
- College of Natural Sciences, Makerere University, Kampala, Uganda
- Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria
| | - R Weka
- Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria
| | - V Muwanika
- College of Agricultural & Environmental Sciences, Makerere University, Kampala, Uganda
| | - P D Luka
- Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria
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Penrith ML, van Heerden J, Pfeiffer DU, Oļševskis E, Depner K, Chenais E. Innovative Research Offers New Hope for Managing African Swine Fever Better in Resource-Limited Smallholder Farming Settings: A Timely Update. Pathogens 2023; 12:355. [PMID: 36839627 PMCID: PMC9963711 DOI: 10.3390/pathogens12020355] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/17/2023] [Accepted: 02/19/2023] [Indexed: 02/23/2023] Open
Abstract
African swine fever (ASF) in domestic pigs has, since its discovery in Africa more than a century ago, been associated with subsistence pig keeping with low levels of biosecurity. Likewise, smallholder and backyard pig farming in resource-limited settings have been notably affected during the ongoing epidemic in Eastern Europe, Asia, the Pacific, and Caribbean regions. Many challenges to managing ASF in such settings have been identified in the ongoing as well as previous epidemics. Consistent implementation of biosecurity at all nodes in the value chain remains most important for controlling and preventing ASF. Recent research from Asia, Africa, and Europe has provided science-based information that can be of value in overcoming some of the hurdles faced for implementing biosecurity in resource-limited contexts. In this narrative review we examine a selection of these studies elucidating innovative solutions such as shorter boiling times for inactivating ASF virus in swill, participatory planning of interventions for risk mitigation for ASF, better understanding of smallholder pig-keeper perceptions and constraints, modified culling, and safe alternatives for disposal of carcasses of pigs that have died of ASF. The aim of the review is to increase acceptance and implementation of science-based approaches that increase the feasibility of managing, and the possibility to prevent, ASF in resource-limited settings. This could contribute to protecting hundreds of thousands of livelihoods that depend upon pigs and enable small-scale pig production to reach its full potential for poverty alleviation and food security.
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Affiliation(s)
- Mary-Louise Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa
| | - Juanita van Heerden
- Transboundary Animal Diseases, Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria 0110, South Africa
| | - Dirk U. Pfeiffer
- Centre for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China
- Department of Pathobiology and Population Sciences, Veterinary Epidemiology, Economics, and Public Health Group, Royal Veterinary College, Hatfield AL9 7TA, UK
| | - Edvīns Oļševskis
- Food and Veterinary Service, LV-1050 Riga, Latvia
- Institute of Food Safety, Animal Health and Environment, “BIOR“, LV-1076 Riga, Latvia
| | - Klaus Depner
- Friedrich-Loeffler-Institute, Greifswald-Insel Riems, 17493 Greifswald, Germany
| | - Erika Chenais
- Department of Disease Control and Epidemiology, National Veterinary Institute, S-751 89 Uppsala, Sweden
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Penrith ML, Van Heerden J, Heath L, Abworo EO, Bastos ADS. Review of the Pig-Adapted African Swine Fever Viruses in and Outside Africa. Pathogens 2022; 11:pathogens11101190. [PMID: 36297247 PMCID: PMC9609104 DOI: 10.3390/pathogens11101190] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/08/2022] [Accepted: 10/11/2022] [Indexed: 12/04/2022] Open
Abstract
The region in eastern, central and southern Africa (ECSA) where African swine fever (ASF) originated in a sylvatic cycle is home to all the p72 genotypes of ASF virus identified so far. While 20 of the 24 genotypes have been isolated from outbreaks in domestic pigs in the region, only five of the genotypes (I, II, VIII, IX, X) have an extended field presence associated with domestic pigs. Of the genotypes that appear to be strongly adapted to domestic pigs, two have spread beyond the African continent and have been the focus of efforts to develop vaccines against ASF. Most of the experimental ASF vaccines described do not protect against a wider spectrum of viruses and may be less useful in the event of incursions of different strains or where multiple genotypes co-exist. The other three pig-adapted strains that are currently restricted to the ECSA region might spread, and priority should be given to understanding not only the genetic and antigenic characteristics of these viruses but also their history. We review historic and current knowledge of the distribution of these five virus genotypes, and note that as was the case for genotype II, some pig-associated viruses have the propensity for geographical range expansion. These features are valuable for prioritizing vaccine-development efforts to ensure a swift response to virus escape. However, whilst ASF vaccines are critical for high-production systems, global food security relies on parallel efforts to improve biosecurity and pig production in Africa and on continued ASFV surveillance and characterisation in the ECSA region.
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Affiliation(s)
- Mary-Louise Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa
- Correspondence: or
| | - Juanita Van Heerden
- Transboundary Animal Diseases, Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria 0110, South Africa
| | - Livio Heath
- Transboundary Animal Diseases, Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria 0110, South Africa
| | - Edward Okoth Abworo
- Biosciences, Animal and Human Health Program, International Livestock Research Institute (ILRI), Nairobi 00100, Kenya
| | - Armanda D. S. Bastos
- Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0028, South Africa
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Genetic Characterization of African Swine Fever Virus in Various Outbreaks in Central and Southern Vietnam During 2019-2021. Curr Microbiol 2022; 79:341. [PMID: 36209177 DOI: 10.1007/s00284-022-03033-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 09/08/2022] [Indexed: 11/03/2022]
Abstract
This study aimed to identify potential genetic diversity among African swine fever virus (ASFV) strains circulating in central and southern Vietnam. Thirty ASFV strains were collected from domestic pigs and convalescent pigs with ASFV-infected clinical signs from 19 different provinces of central and southern Vietnam during 2019-2021. A portion of the B646L (p72) gene and the entire E183L (p54), CP204L (p30), and B602L (CVR) genes were amplified, purified, and sequenced. Web-based BLAST and MEGA X software were used for sequence analysis. Analysis of the partial B646L (p72) gene, the full-length E183L (p54) and CP204L (p30) genes, and the central hypervariable region (CVR) of the B602L gene sequence showed that all 30 ASFV isolates belonged to genotype II and were 100% identical to the previously identified strains in Vietnam and China. Analysis of the p72, p54, and p30 regions did not indicate any change in the nucleotide and amino acid sequences among these strains in 3 years of research. No novel variant was found in the CVR within the B602L gene. Analysis of the CVR showed that these ASFV strains belong to subgroup XXXII. The results of this study revealed that these ASFVs shared high similarity with ASFV isolates detected previously in northern Vietnam and China. Taken together, the results of this study and a previous study in Vietnam showed high stability and no genetic diversity in the ASFV genome.
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Zeng D, Qian B, Li Y, Zong K, Peng W, Liao K, Yu X, Sun J, Lv X, Ding L, Wang M, Zhou T, Jiang Y, Li J, Xue F, Wu X, Dai J. Prospects for the application of infectious virus detection technology based on propidium monoazide in African swine fever management. Front Microbiol 2022; 13:1025758. [PMID: 36246220 PMCID: PMC9563241 DOI: 10.3389/fmicb.2022.1025758] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
African swine fever (ASF) is a hemorrhagic and often fatal disease occurring in domestic pigs and wild boars. ASF can potentially greatly impact the global trade of pigs and pork products and threaten global food security. Outbreaks of ASF must be notified to the World Organization for Animal Health. In this study, we analyzed the feasibility of applying propidium monoazide (PMA) pretreatment-based infectious virus detection technology to ASF prevention and control and investigated the prospects of applying this technology for epidemic monitoring, disinfection effect evaluation, and drug development. PMA as a nucleic acid dye can enter damaged cells and undergo irreversible covalent crosslinking with nucleic acid under halogen light to prevent its amplification. Although this technology has been widely used for the rapid detection of viable bacteria, its application in viruses is rare. Therefore, we analyzed the theoretical feasibility of applying this technology to the African swine fever virus (ASFV) in terms of gene and cell composition. Rapid infectious ASFV detection technology based on PMA pretreatment would greatly enhance all aspects of ASF prevention and control, such as epidemic monitoring, disinfection treatment, and drug development. The introduction of this technology will also greatly improve the ability to prevent and control ASF.
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Affiliation(s)
- Dexin Zeng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
- Technical Center of Hefei Customs, Hefei, China
| | - Bingxu Qian
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
| | - Yunfei Li
- Technical Center of Hefei Customs, Hefei, China
- Technology Center of Hefei Customs, Anhui Province Key Laboratory of Analysis and Detection for Food Safety, Hefei, China
| | - Kai Zong
- Technical Center of Hefei Customs, Hefei, China
- Technology Center of Hefei Customs, Anhui Province Key Laboratory of Analysis and Detection for Food Safety, Hefei, China
| | - Wanqing Peng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
| | - Kai Liao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
| | - Xiaofeng Yu
- Technical Center of Hefei Customs, Hefei, China
- Technology Center of Hefei Customs, Anhui Province Key Laboratory of Analysis and Detection for Food Safety, Hefei, China
| | | | - Xiaying Lv
- Technical Center of Hefei Customs, Hefei, China
| | - Liu Ding
- Technical Center of Hefei Customs, Hefei, China
| | - Manman Wang
- Technical Center of Hefei Customs, Hefei, China
| | | | - Yuan Jiang
- Animal, Plant and Food Inspection Center of Nanjing Customs, Nanjing, China
| | - Jinming Li
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Feng Xue
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
- Sanya Institute of Nanjing Agricultural University, Sanya, China
- *Correspondence: Feng Xue,
| | - Xiaodong Wu
- China Animal Health and Epidemiology Center, Qingdao, China
- *Correspondence: Feng Xue,
| | - Jianjun Dai
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, China
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10
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Shi K, Liu H, Yin Y, Si H, Long F, Feng S. Molecular Characterization of African Swine Fever Virus From 2019-2020 Outbreaks in Guangxi Province, Southern China. Front Vet Sci 2022; 9:912224. [PMID: 35782548 PMCID: PMC9240437 DOI: 10.3389/fvets.2022.912224] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
African swine fever virus (ASFV) causes contagious hemorrhagic disease of pigs with high morbidity and mortality. To identify the molecular characteristics of ASFV strains circulating in Guangxi province, southern China, a total of 336 tissue samples collected from 336 domestic pigs that died as a result of severe hemorrhagic disease during 2019–2020 were tested for ASFV. Furthermore, 66 ASFV strains were genetically characterized by sequence analysis of the C-terminal region of B646L (p72) gene, the complete E183L (p54) gene, the variable region of EP402R (CD2v) gene, the central variable region (CVR) of B602L gene, the full MGF505-2R gene, and the tandem repeat sequence (TRS) within intergenic region (IGR) between the I73R and I329L (I73R/I329L) genes. Phylogenetic analysis revealed that the ASFV strains from Guangxi province belonged to genotypes I and II based on the B646L (p72) and E183L (p54) genes, and there were eight different tetrameric TRS variants based on the CVR of B602L gene. Phylogenetic analysis of the EP402R (CD2v) gene revealed that these ASFV strains belonged to serogroups 4 and 8. Eight of the 66 strains belonged to genotype I and serogroup 4, and showed deletion of whole MGF505-2R gene. The sequence analysis of the IGR between the I73R/I329L genes showed that IGR II and III variants were co-circulating in Guangxi province. The results indicated that ASFV strains circulating in Guangxi province during 2019–2020 outbreaks showed high genetic diversity, of which genotypes I and II, as well as serogroups 4 and 8, were simultaneously circulating in Guangxi province, and there existed wild-type and naturally gene-deleted strains in the field. This is the first detailed report on the molecular characterization of the ASFV strains circulating in southern China, and serogroup 4 in China.
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Affiliation(s)
- Kaichuang Shi
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
- College of Animal Science and Technology, Guangxi University, Nanning, China
- *Correspondence: Kaichuang Shi
| | - Huixin Liu
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Yanwen Yin
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Hongbin Si
- College of Animal Science and Technology, Guangxi University, Nanning, China
- Hongbin Si
| | - Feng Long
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Shuping Feng
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
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11
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Shen ZJ, Jia H, Xie CD, Shagainar J, Feng Z, Zhang X, Li K, Zhou R. Bayesian Phylodynamic Analysis Reveals the Dispersal Patterns of African Swine Fever Virus. Viruses 2022; 14:v14050889. [PMID: 35632631 PMCID: PMC9147906 DOI: 10.3390/v14050889] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/01/2022] [Accepted: 04/05/2022] [Indexed: 02/07/2023] Open
Abstract
The evolutionary and demographic history of African swine fever virus (ASFV) is potentially quite valuable for developing efficient and sustainable management strategies. In this study, we performed phylogenetic, phylodynamic, and phylogeographic analyses of worldwide ASFV based on complete ASFV genomes, B646L gene, and E183L gene sequences obtained from NCBI to understand the epidemiology of ASFV. Bayesian phylodynamic analysis and phylogenetic analysis showed highly similar results of group clustering between E183L and the complete genome. The evidence of migration and the demographic history of ASFV were also revealed by the Bayesian phylodynamic analysis. The evolutionary rate was estimated to be 1.14 × 10−5 substitution/site/year. The large out-migration from the viral population in South Africa played a crucial role in spreading the virus worldwide. Our study not only provides resources for the better utilization of genomic data but also reveals the comprehensive worldwide evolutionary history of ASFV with a broad sampling window across ~70 years. The characteristics of the virus spatiotemporal transmission are also elucidated, which could be of great importance for devising strategies to control the virus.
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Affiliation(s)
- Zhao-Ji Shen
- State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (Z.-J.S.); (H.J.); (C.-D.X.); (J.S.)
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, College of Life Science and Engineering, Foshan University, Foshan 528231, China;
| | - Hong Jia
- State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (Z.-J.S.); (H.J.); (C.-D.X.); (J.S.)
| | - Chun-Di Xie
- State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (Z.-J.S.); (H.J.); (C.-D.X.); (J.S.)
| | - Jurmt Shagainar
- State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (Z.-J.S.); (H.J.); (C.-D.X.); (J.S.)
| | - Zheng Feng
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, College of Life Science and Engineering, Foshan University, Foshan 528231, China;
| | - Xiaodong Zhang
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China;
| | - Kui Li
- Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China
- Correspondence: (K.L.); (R.Z.)
| | - Rong Zhou
- State Key Laboratory of Animal Nutrition, Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (Z.-J.S.); (H.J.); (C.-D.X.); (J.S.)
- Correspondence: (K.L.); (R.Z.)
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12
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A Multi-Laboratory Comparison of Methods for Detection and Quantification of African Swine Fever Virus. Pathogens 2022; 11:pathogens11030325. [PMID: 35335649 PMCID: PMC8949307 DOI: 10.3390/pathogens11030325] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/26/2022] [Accepted: 03/03/2022] [Indexed: 02/01/2023] Open
Abstract
African swine fever is a viral disease of the family Suidae. Methods to detect and quantify African swine fever virus (ASFV) include qPCR and virus infectivity assays. Individual laboratories often use in-house procedures for these assays, which can hamper the comparison of results. The objective of this study was to estimate the probability of ASFV detection using these assays, and to determine the inter-test correlations between results. This was achieved by testing a panel of 80 samples at three reference laboratories. Samples were analysed using nucleic acid extraction and qPCR, as well as virus infectivity assays. For qPCR, a very high probability (ranging from 0.96 to 1.0) of detecting ASFV DNA was observed for all tested systems. For virus infectivity assays in cells, the probability of detecting infectious ASFV varied from 0.68 to 0.90 and was highest using pulmonary alveolar macrophages, followed by MARC145 cells, peripheral blood monocytes, and finally wild boar lung cells. Intraclass correlation coefficient estimates of 0.97 (0.96–0.98) between qPCR methods, 0.80 (0.74–0.85) to 0.94 (0.92–0.96) between virus infectivity assays, and 0.77 (0.68–0.83) to 0.95 (0.93–0.96) between qPCR methods and virus infectivity assays were obtained. These findings show that qPCR gives the highest probability for the detection of ASFV.
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13
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Penrith ML, Kivaria FM. One hundred years of African swine fever in Africa: where have we been, where are we now, where are we going? Transbound Emerg Dis 2022; 69:e1179-e1200. [PMID: 35104041 DOI: 10.1111/tbed.14466] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 11/26/2022]
Abstract
One hundred years have passed since the first paper on African swine fever (ASF) was published by Montgomery in 1921. With no vaccine, ineffectiveness of prevention and control measures, and lack of common interest in eradicating the disease, ASF has proven to be one of the most devastating diseases because of its significant sanitary and socioeconomic consequences. The rapid spread of the disease on the European and Asian continents and its recent appearance in the Caribbean puts all countries at great risk because of global trade. The incidence of ASF has also increased on the African continent over the last few decades, extending its distribution far beyond the area in which the ancient sylvatic cycle is present with its complex epidemiological transmission pathways involving virus reservoirs in ticks and wild African Suidae. Both in that area and elsewhere, efficient transmission by infected domestic pigs and virus resistance in infected animal products and fomites mean that human driven factors along the pig value chain are the dominant impediments for its prevention, control, and eradication. Control efforts in Africa are furthermore hampered by the lack of information about the size and location of the fast-growing pig population, particularly in the dynamic smallholder sector that constitutes up to 90% of pig production in the region. A vaccine that will be both affordable and effective against multiple genotypes of the virus is not a short-term reality. Therefore, a strategy for management of ASF in sub-Saharan Africa is needed to provide a roadmap for the way forward for the continent. This review explores the progression of ASF and our knowledge of it through research over a century in Africa, our current understanding of ASF, and what must be done going forwards to improve the African situation and contribute to global prevention and control. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Mary Louise Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Fredrick Mathias Kivaria
- Food and Agriculture Organization of the UN, Block P, Level 3, United Nations Complex, UN Avenue, Gigiri, Nairobi, PO Box: 30470, GPO, Nairobi, 00100, Kenya
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14
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A systematic review of genotypes and serogroups of African swine fever virus. Virus Genes 2022; 58:77-87. [PMID: 35061204 PMCID: PMC8778497 DOI: 10.1007/s11262-021-01879-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 11/20/2021] [Indexed: 11/04/2022]
Abstract
African swine fever virus (ASFV) is the causative agent of African swine fever (ASF). The virus causes an acute highly hemorrhagic disease in domestic pigs, with high mortality. Although the overall genome mutation rate of ASFV, a large DNA virus, is relatively low, ASFV exhibits genetic and antigenic diversity. ASFV can be classified into 24 genotypes on the basis of the B646L gene. Cross-protected ASFV strains can be divided into eight serogroups on the basis of antibody-mediated hemadsorption inhibition. Here, we review research progress on ASFV genotyping and serogrouping, and explain how this information assists in the rapid identification of virus origin during ASF outbreaks and will aid in the development of ASF vaccines.
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15
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Wei N, Zheng B, Niu J, Chen T, Ye J, Si Y, Cao S. Rapid Detection of Genotype II African Swine Fever Virus Using CRISPR Cas13a-Based Lateral Flow Strip. Viruses 2022; 14:v14020179. [PMID: 35215773 PMCID: PMC8879322 DOI: 10.3390/v14020179] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/14/2022] [Accepted: 01/16/2022] [Indexed: 02/01/2023] Open
Abstract
The African swine fever virus (ASFV) is a dsDNA virus that can cause serious, highly infectious, and fatal diseases in wild boars and domestic pigs. The ASFV has brought enormous economic loss to many countries, and no effective vaccine or treatment for the ASFV is currently available. Therefore, the on-site rapid and accurate detection of the ASFV is key to the timely implementation of control. The RNA-guided, RNA-targeting CRISPR effector CRISPR-associated 13 (Cas13a; previously known as C2c2) exhibits a “collateral effect” of promiscuous RNase activity upon the target recognition. The collateral cleavage activity of LwCas13a is activated to degrade the non-targeted RNA, when the crRNA of LwCas13a binds to the target RNA. In this study, we developed a rapid and sensitive ASFV detection method based on the collateral cleavage activity of LwCas13a, which combines recombinase-aided amplification (RAA) and a lateral flow strip (named CRISPR/Cas13a-LFD). The method was an isothermal detection at 37 °C, and the detection can be used for visual readout. The detection limit of the CRISPR/Cas13a-LFD was 101 copies/µL of p72 gene per reaction, and the detection process can be completed within an hour. The assay showed no cross-reactivity to eight other swine viruses, including classical swine fever virus (CSFV), and has a 100% coincidence rate with real-time PCR detection of the ASFV in 83 clinical samples. Overall, this method is sensitive, specific, and practicable onsite for the ASFV detection, showing a great application potential for monitoring the ASFV in the field.
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Affiliation(s)
- Ning Wei
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Bohan Zheng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Junjun Niu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Tao Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Jing Ye
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Youhui Si
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Correspondence: (Y.S.); (S.C.)
| | - Shengbo Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (N.W.); (B.Z.); (J.N.); (T.C.); (J.Y.)
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Correspondence: (Y.S.); (S.C.)
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16
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Zhang Y, Ke J, Zhang J, Yue H, Chen T, Li Q, Zhou X, Qi Y, Zhu R, Wang S, Miao F, Zhang S, Li N, Mi L, Yang J, Yang J, Han X, Wang L, Li Y, Hu R. I267L Is Neither the Virulence- Nor the Replication-Related Gene of African Swine Fever Virus and Its Deletant Is an Ideal Fluorescent-Tagged Virulence Strain. Viruses 2021; 14:v14010053. [PMID: 35062257 PMCID: PMC8777747 DOI: 10.3390/v14010053] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 12/22/2021] [Accepted: 12/27/2021] [Indexed: 12/29/2022] Open
Abstract
African swine fever virus (ASFV) is the causative agent of African swine fever (ASF) which reaches up to 100% case fatality in domestic pigs and wild boar and causes significant economic losses in the swine industry. Lack of knowledge of the function of ASFV genes is a serious impediment to the development of the safe and effective vaccine. Herein, I267L was identified as a relative conserved gene and an early expressed gene. A recombinant virus (SY18ΔI267L) with I267L gene deletion was produced by replacing I267L of the virulent ASFV SY18 with enhanced green fluorescent protein (EGFP) cassette. The replication kinetics of SY18ΔI267L is similar to that of the parental isolate in vitro. Moreover, the doses of 102.0 TCID50 (n = 5) and 105.0 TCID50 (n = 5) SY18ΔI267L caused virulent phenotype, severe clinical signs, viremia, high viral load, and mortality in domestic pigs inoculated intramuscularly as the virulent parental virus strain. Therefore, the deletion of I267L does not affect the replication or the virulence of ASFV. Utilizing the fluorescent-tagged virulence deletant can be easy to gain a visual result in related research such as the inactivation effect of some drugs, disinfectants, extracts, etc. on ASFV.
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Affiliation(s)
- Yanyan Zhang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Junnan Ke
- College of Animal Science and Technology, College of Veterinary Medicine, Jilin Agricultural University, Changchun 130118, China; (J.K.); (J.Y.)
| | - Jingyuan Zhang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Huixian Yue
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Teng Chen
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Qian Li
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Xintao Zhou
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Yu Qi
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Rongnian Zhu
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Shuchao Wang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Faming Miao
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Shoufeng Zhang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Nan Li
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Lijuan Mi
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Jinjin Yang
- College of Animal Science and Technology, College of Veterinary Medicine, Jilin Agricultural University, Changchun 130118, China; (J.K.); (J.Y.)
| | - Jinmei Yang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Xun Han
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Lidong Wang
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
| | - Ying Li
- College of Animal Science and Technology, College of Veterinary Medicine, Jilin Agricultural University, Changchun 130118, China; (J.K.); (J.Y.)
- Correspondence: (Y.L.); (R.H.)
| | - Rongliang Hu
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China; (Y.Z.); (J.Z.); (H.Y.); (T.C.); (Q.L.); (X.Z.); (Y.Q.); (R.Z.); (S.W.); (F.M.); (S.Z.); (N.L.); (L.M.); (J.Y.); (X.H.); (L.W.)
- Correspondence: (Y.L.); (R.H.)
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17
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Njau EP, Machuka EM, Cleaveland S, Shirima GM, Kusiluka LJ, Okoth EA, Pelle R. African Swine Fever Virus (ASFV): Biology, Genomics and Genotypes Circulating in Sub-Saharan Africa. Viruses 2021; 13:2285. [PMID: 34835091 PMCID: PMC8623397 DOI: 10.3390/v13112285] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 10/17/2021] [Accepted: 11/03/2021] [Indexed: 12/22/2022] Open
Abstract
African swine fever (ASF) is a highly infectious and fatal haemorrhagic disease of pigs that is caused by a complex DNA virus of the genus Asfivirus and Asfarviridae African suids family. The disease is among the most devastating pig diseases worldwide including Africa. Although the disease was first reported in the 19th century, it has continued to spread in Africa and other parts of the world. Globally, the rising demand for pork and concomitant increase in transboundary movements of pigs and pork products is likely to increase the risk of transmission and spread of ASF and pose a major challenge to the pig industry. Different genotypes of the ASF virus (ASFV) with varying virulence have been associated with different outbreaks in several countries in sub-Saharan Africa (SSA) and worldwide, and understanding genotype circulation will be important for ASF prevention and control strategies. ASFV genotypes unique to Africa have also been reported in SSA. This review briefly recounts the biology, genomics and genotyping of ASFV and provides an account of the different genotypes circulating in SSA. The review also highlights prevention, control and progress on vaccine development and identifies gaps in knowledge of ASFV genotype circulation in SSA that need to be addressed.
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Affiliation(s)
- Emma P. Njau
- Biosciences Eastern and Central Africa—International Livestock Research Institute Hub, P.O. Box 30709, Nairobi 00100, Kenya; (E.M.M.); (E.A.O.); (R.P.)
- Nelson Mandela African Institution of Science and Technology, Arusha P.O. Box 447, Tanzania; (S.C.); (G.M.S.); (L.J.K.)
- College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Chuo Kikuu, Morogoro P.O. Box 3015, Tanzania
| | - Eunice M. Machuka
- Biosciences Eastern and Central Africa—International Livestock Research Institute Hub, P.O. Box 30709, Nairobi 00100, Kenya; (E.M.M.); (E.A.O.); (R.P.)
| | - Sarah Cleaveland
- Nelson Mandela African Institution of Science and Technology, Arusha P.O. Box 447, Tanzania; (S.C.); (G.M.S.); (L.J.K.)
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Gabriel M. Shirima
- Nelson Mandela African Institution of Science and Technology, Arusha P.O. Box 447, Tanzania; (S.C.); (G.M.S.); (L.J.K.)
| | - Lughano J. Kusiluka
- Nelson Mandela African Institution of Science and Technology, Arusha P.O. Box 447, Tanzania; (S.C.); (G.M.S.); (L.J.K.)
- College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Chuo Kikuu, Morogoro P.O. Box 3015, Tanzania
- Mzumbe University, Morogoro P.O. Box 1, Tanzania
| | - Edward A. Okoth
- Biosciences Eastern and Central Africa—International Livestock Research Institute Hub, P.O. Box 30709, Nairobi 00100, Kenya; (E.M.M.); (E.A.O.); (R.P.)
| | - Roger Pelle
- Biosciences Eastern and Central Africa—International Livestock Research Institute Hub, P.O. Box 30709, Nairobi 00100, Kenya; (E.M.M.); (E.A.O.); (R.P.)
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18
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Njau EP, Domelevo Entfellner JB, Machuka EM, Bochere EN, Cleaveland S, Shirima GM, Kusiluka LJ, Upton C, Bishop RP, Pelle R, Okoth EA. The first genotype II African swine fever virus isolated in Africa provides insight into the current Eurasian pandemic. Sci Rep 2021; 11:13081. [PMID: 34158551 PMCID: PMC8219699 DOI: 10.1038/s41598-021-92593-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 05/24/2021] [Indexed: 02/05/2023] Open
Abstract
African swine fever (ASF) caused by the African swine fever virus (ASFV) is ranked by OIE as the most important source of mortality in domestic pigs globally and is indigenous to African wild suids and soft ticks. Despite two ASFV genotypes causing economically devastating epidemics outside the continent since 1961, there have been no genome-level analyses of virus evolution in Africa. The virus was recently transported from south-eastern Africa to Georgia in 2007 and has subsequently spread to Russia, eastern Europe, China, and south-east Asia with devastating socioeconomic consequences. To date, two of the 24 currently described ASFV genotypes defined by sequencing of the p72 gene, namely genotype I and II, have been reported outside Africa, with genotype II being responsible for the ongoing pig pandemic. Multiple complete genotype II genome sequences have been reported from European, Russian and Chinese virus isolates but no complete genome sequences have yet been reported from Africa. We report herein the complete genome of a Tanzanian genotype II isolate, Tanzania/Rukwa/2017/1, collected in 2017 and determined using an Illumina short read strategy. The Tanzania/Rukwa/2017/1 sequence is 183,186 bp in length (in a single contig) and contains 188 open reading frames. Considering only un-gapped sites in the pairwise alignments, the new sequence has 99.961% identity with the updated Georgia 2007/1 reference isolate (FR682468.2), 99.960% identity with Polish isolate Pol16_29413_o23 (MG939586) and 99.957% identity with Chinese isolate ASFV-wbBS01 (MK645909.1). This represents 73 single nucleotide polymorphisms (SNPs) relative to the Polish isolate and 78 SNPs with the Chinese genome. Phylogenetic analysis indicated that Tanzania/Rukwa/2017/1 clusters most closely with Georgia 2007/1. The majority of the differences between Tanzania/Rukwa/2017/1 and Georgia 2007/1 genotype II genomes are insertions/deletions (indels) as is typical for ASFV. The indels included differences in the length and copy number of the terminal multicopy gene families, MGF 360 and 110. The Rukwa2017/1 sequence is the first complete genotype II genome from a precisely mapped locality in Africa, since the exact origin of Georgia2007/1 is unknown. It therefore provides baseline information for future analyses of the diversity and phylogeography of this globally important genetic sub-group of ASF viruses.
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Affiliation(s)
- Emma P Njau
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya.
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.
- Sokoine University of Agriculture, P. O. Box 3019, Morogoro, Tanzania.
| | | | - Eunice M Machuka
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya
| | - Edwina N Bochere
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya
| | - Sarah Cleaveland
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Gabriel M Shirima
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Lughano J Kusiluka
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Mzumbe University, Morogoro, Tanzania
| | - Chris Upton
- Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 3P6, Canada
| | - Richard P Bishop
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya
| | - Roger Pelle
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya
| | - Edward A Okoth
- Biosciences Eastern and Central Africa-International Livestock Research Institute Hub, Nairobi, Kenya
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19
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Gao L, Sun X, Yang H, Xu Q, Li J, Kang J, Liu P, Zhang Y, Wang Y, Huang B. Epidemic situation and control measures of African Swine Fever Outbreaks in China 2018-2020. Transbound Emerg Dis 2021; 68:2676-2686. [PMID: 33369865 DOI: 10.1111/tbed.13968] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 12/14/2020] [Accepted: 12/23/2020] [Indexed: 01/18/2023]
Abstract
As of 21 April 2020, 176 ASF outbreaks have occurred in China. For each outbreak, an investigation was conducted, including historical data retrieval and traceability of potential contacts. The purpose of this study is to conduct a preliminary analysis of the data obtained from the outbreak investigations, including an investigation of the possible contributing factors of the spread of ASF in China. Based on the epidemic situation and the policies issued, the entire epidemic can be divided into three phases. 71 outbreaks were reported between 3 August 2018 and 17 November 2018; 44 outbreaks between 19 November 2018 and 30 March 2019; and 61 outbreaks between 4 April 2019 and 12 April 2020. Based on the reported outbreaks, the proportional rate of outbreaks in small farms (livestock ≤ 500, 127/168) is significantly higher than that of medium (501 ≤ livestock < 2,000, 14/168; 2001 ≤ livestock ≤ 5,000, 9/168) and large farms (livestock ≥ 5,001, 18/168). The odds of infection related to swill feeding (OR = 2.5, 95% CI, 1.5-4.3) and the mechanical dissemination of vehicles and personnel (OR = 2.7, 95% CI, 1.6-4.5) are significantly higher than those of pigs and pig production transportation. Swill feeding is the major contributing factor for small farms while mechanical dissemination of vehicles and personnel is the major contributing factor for large farms. The average duration from the beginning of the infection to the official outbreak report is gradually decreasing, which means that response speed of industry entities and the animal husbandry and veterinary departments from the beginning of the infection to the outbreak report is gradually increasing. Based on the analysis for ASF outbreaks, some policies and suggestions were put forward, such as improving the biosecurity level of the farms, as well as strengthening the supervision of breeding, transportation and slaughter.
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Affiliation(s)
- Lu Gao
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Xiangdong Sun
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Honglin Yang
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Quangang Xu
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Juan Li
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Jingli Kang
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Ping Liu
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Yi Zhang
- ZunYi Medical University, Zunyi, China
| | - Youming Wang
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Baoxu Huang
- China Animal Health and Epidemiology Center, Qingdao, China
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20
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Amar S, De Boni L, de Voux A, Heath L, Geertsma P. An outbreak of African swine fever in small-scale pigs, Gauteng, South Africa, July 2020. Int J Infect Dis 2021; 110 Suppl 1:S44-S49. [PMID: 33895412 DOI: 10.1016/j.ijid.2021.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/01/2021] [Accepted: 04/03/2021] [Indexed: 10/21/2022] Open
Abstract
OBJECTIVES Since 2012, outbreaks of African swine fever (ASF) in domestic pigs have increased outside of South Africa's ASF control zone. This study describes the epidemiological investigation and findings of an ASF outbreak in a small-scale pig unit in Gauteng Province and makes recommendations to prevent future outbreaks. METHODS PCR testing and molecular analysis were performed on pig tissue samples. Veterinary services conducted epidemiological investigations, forward and backward tracing, and surveillance. Farm management and biosecurity practices were assessed. Quarantine, culling, carcass disposal, and disinfection were implemented. RESULTS ASF virus genotype I was detected. A concurrent ASF outbreak in neighbouring Mpumalanga Province was identified as a possible source. Inadequate biosecurity measures probably facilitated viral transmission. Potential mechanisms for the introduction of the ASF virus include swill feeding practices, free roaming of pigs, scavenging, illegal slaughter, and trade of pig products within the community. CONCLUSIONS Molecular typing of the ASF virus linked the outbreak to an ongoing ASF outbreak in Mpumalanga Province. Pig enterprises with poor biosecurity practices may face greater risk of ASF introduction. Small-scale pig keepers should be targeted for ASF awareness and education campaigns. Innovative and cost-effective biosecurity solutions are needed in this resource-poor setting.
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Affiliation(s)
- Shira Amar
- South African Field Epidemiology Training Programme, Division of Public Health, Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, Johannesburg, South Africa; Division of Epidemiology and Biostatistics, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa.
| | - Liesl De Boni
- Gauteng Veterinary Services, Gauteng Department of Agriculture and Rural Development (GDARD), Johannesburg, South Africa
| | - Alex de Voux
- South African Field Epidemiology Training Programme, Division of Public Health, Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, Johannesburg, South Africa; Division of Epidemiology and Biostatistics, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Livio Heath
- Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria, South Africa
| | - Peter Geertsma
- Gauteng Veterinary Services, Gauteng Department of Agriculture and Rural Development (GDARD), Johannesburg, South Africa
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21
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Identification of Escherichia coli and Related Enterobacteriaceae and Examination of Their Phenotypic Antimicrobial Resistance Patterns: A Pilot Study at A Wildlife-Livestock Interface in Lusaka, Zambia. Antibiotics (Basel) 2021; 10:antibiotics10030238. [PMID: 33652871 PMCID: PMC7996741 DOI: 10.3390/antibiotics10030238] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/22/2021] [Accepted: 02/22/2021] [Indexed: 12/12/2022] Open
Abstract
A cross-sectional study was used to identify and assess prevalence and phenotypic antimicrobial resistance (AMR) profiles of Escherichia coli and other enterobacteria isolated from healthy wildlife and livestock cohabiting at a 10,000 acres game ranch near Lusaka, Zambia. Purposive sampling was used to select wildlife and livestock based on similarities in behavior, grazing habits and close interactions with humans. Isolates (n = 66) from fecal samples collected between April and August 2018 (n = 84) were examined following modified protocols for bacteria isolation, biochemical identification, molecular detection, phylogenetic analysis, and antimicrobial susceptibility testing by disc diffusion method. Data were analyzed using R software, Genetyx ver.12 and Mega 6. Using Applied Profile Index 20E kit for biochemical identification, polymerase chain reaction assay and sequencing, sixty-six isolates were identified to species level, of which Escherichia coli (72.7%, 48/66), E. fergusonii (1.5%, 1/66), Shigella sonnei (22.7%, 14/66), Sh. flexinerri (1.5%, 1/66) and Enterobacteriaceae bacterium (1.5%, 1/66), and their relationships were illustrated in a phylogenetic tree. Phenotypic antimicrobial resistance or intermediate sensitivity expression to at least one antimicrobial agent was detected in 89.6% of the E. coli, and 73.3% of the Shigella isolates. The E. coli isolates exhibited the highest resistance rates to ampicillin (27%), ceftazidime (14.3%), cefotaxime (9.5%), and kanamycin (9.5%). Multidrug resistance (MDR) was detected in 18.8% of E. coli isolates while only 13.3% Shigella isolates showed MDR. The MDR was detected among isolates from impala and ostrich (wild animals in which no antimicrobial treatment was used), and in isolates from cattle, pigs, and goats (domesticated animals). This study indicates the possible transmission of drug-resistant microorganisms between animals cohabiting at the wildlife–livestock interface. It emphasizes the need for further investigation of the role of wildlife in the development and transmission of AMR, which is an issue of global concern.
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22
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Development of A Super-Sensitive Diagnostic Method for African Swine Fever Using CRISPR Techniques. Virol Sin 2021; 36:220-230. [PMID: 33411169 DOI: 10.1007/s12250-020-00323-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 10/20/2020] [Indexed: 11/27/2022] Open
Abstract
African swine fever (ASF) is an infectious disease caused by African swine fever virus (ASFV) with clinical symptoms of high fever, hemorrhages and high mortality rate, posing a threat to the global swine industry and food security. Quarantine and control of ASFV is crucial for preventing swine industry from ASFV infection. In this study, a recombinase polymerase amplification (RPA)-CRISPR-based nucleic acid detection method was developed for diagnosing ASF. As a highly sensitive method, RPA-CRISPR can detect even a single copy of ASFV plasmid and genomic DNA by determining fluorescence signal induced by collateral cleavage of CRISPR-lwCas13a (previously known as C2c2) through quantitative real-time PCR (qPCR) and has the same or even higher sensitivity than the traditional qPCR method. A lateral flow strip was developed and used in combination with RPA-CRISPR for ASFV detection with the same level of sensitivity of TaqMan qPCR. Likewise, RPA-CRISPR is capable of distinguishing ASFV genomic DNA from viral DNA/RNA of other porcine viruses without any cross-reactivity. This diagnostic method is also available for diagnosing ASFV clinical DNA samples with coincidence rate of 100% for both ASFV positive and negative samples. RPA-CRISPR has great potential for clinical quarantine of ASFV in swine industry and food security.
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23
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Isolation and Genetic Characterization of African Swine Fever Virus from Domestic Pig Farms in South Korea, 2019. Viruses 2020; 12:v12111237. [PMID: 33143155 PMCID: PMC7693868 DOI: 10.3390/v12111237] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 11/18/2022] Open
Abstract
On 17 September 2019, the first outbreak of African swine fever in a pig farm was confirmed in South Korea. By 9 October, 14 outbreaks of ASF in domestic pigs had been diagnosed in 4 cities/counties. We isolated viruses from all infected farms and performed genetic characterization. The phylogenetic analysis showed that all of fourteen ASFV isolates in South Korea belong to genotype II and serogroup 8. Additionally, all isolates had an intergenic region (IGR) II variant with additional tandem repeat sequences (TRSs) between the I73R and I329L genes and showed characteristics of central variable region (CVR) 1 of the B602L gene and IGR 1 of MGF 505 9R/10R genes. These are identical to the genetic characteristics of some European isolates and Chinese isolates.
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24
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Chambaro HM, Sasaki M, Sinkala Y, Gonzalez G, Squarre D, Fandamu P, Lubaba C, Mataa L, Shawa M, Mwape KE, Gabriël S, Chembensofu M, Carr MJ, Hall WW, Qiu Y, Kajihara M, Takada A, Orba Y, Simulundu E, Sawa H. Evidence for exposure of asymptomatic domestic pigs to African swine fever virus during an inter-epidemic period in Zambia. Transbound Emerg Dis 2020; 67:2741-2752. [PMID: 32434281 DOI: 10.1111/tbed.13630] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 04/05/2020] [Accepted: 05/14/2020] [Indexed: 11/29/2022]
Abstract
African swine fever (ASF) causes persistent outbreaks in endemic and non-endemic regions in Zambia. However, the epidemiology of the disease is poorly understood, particularly during the inter-epidemic periods. We conducted surveillance for ASF in asymptomatic domestic pigs and soft ticks in selected Zambian provinces. While serum samples (n = 1,134) were collected from crossbred pigs from all study sites between 2014 and 2017, whole blood (n = 300) was collected from both crossbred and indigenous pigs in Eastern Province (EP) in 2017. Soft ticks were collected from Mosi-oa-Tunya National Park in Southern Province (SP) in 2019. Sera were screened for antibodies against ASF by ELISA while genome detection in whole blood and soft ticks was conducted by PCR. Ticks were identified morphologically and by phylogenetic analysis of the 16S rRNA gene. Seroprevalence was highest in EP (50.9%, 95% CI [47.0-54.9]) compared to significantly lower rates in SP (2.9%, 95% CI [1.6-5.1]). No antibodies to ASFV were detected in Lusaka Province. In EP, the prevalence of ASFV genome was 11.7% (35/300), significantly higher (OR = 6.2, 95% CI [2.4-16.6]) in indigenous pigs compared to crossbred pigs. The pooled prevalence of ASFV genome in ticks was 11.0%, 95% CI [8.5-13.9]. Free-range husbandry system was the only factor that was significantly associated with seropositive (p < .0001, OR = 39.3) and PCR-positive results (p < .001, OR = 5.7). Phylogenetically, based on the p72 gene, ASFV from Ornithodoros moubata ticks detected in this study belonged to genotype I, but they separated into two distinct clusters. Besides confirming ASF endemicity in EP and the presence of ASFV-infected ticks in SP, these results provide evidence for exposure of domestic pigs to ASFV in non-endemic regions during the inter-epidemic period.
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Affiliation(s)
- Herman M Chambaro
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Ministry of Fisheries and Livestock, Lusaka, Zambia.,Virology Unit, Central Veterinary Research Institute, Lusaka, Zambia
| | - Michihito Sasaki
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yona Sinkala
- Ministry of Fisheries and Livestock, Lusaka, Zambia
| | - Gabriel Gonzalez
- Division of Bioinformatics, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - David Squarre
- Wildlife Veterinary Unit, Department of National Parks and Wildlife, Lusaka, Zambia.,Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland
| | - Paul Fandamu
- Ministry of Fisheries and Livestock, Lusaka, Zambia
| | | | | | - Misheck Shawa
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Kabemba E Mwape
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Sarah Gabriël
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Mwelwa Chembensofu
- Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Michael J Carr
- Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Japan.,National Virus Reference Laboratory, School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - William W Hall
- Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Japan.,National Virus Reference Laboratory, School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland.,Global Virus Network, Baltimore, MD, USA
| | - Yongjin Qiu
- Hokudai Center for Zoonosis Control in Zambia, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Masahiro Kajihara
- Hokudai Center for Zoonosis Control in Zambia, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Ayato Takada
- Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Japan.,Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Yasuko Orba
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Edgar Simulundu
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Japan.,Global Virus Network, Baltimore, MD, USA
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25
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Chastagner A, Pereira de Oliveira R, Hutet E, Le Dimna M, Paboeuf F, Lucas P, Blanchard Y, Dixon L, Vial L, Le Potier MF. Coding-Complete Genome Sequence of an African Swine Fever Virus Strain Liv13/33 Isolate from Experimental Transmission between Pigs and Ornithodoros moubata Ticks. Microbiol Resour Announc 2020; 9:e00185-20. [PMID: 32327506 PMCID: PMC7180279 DOI: 10.1128/mra.00185-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/02/2020] [Indexed: 11/25/2022] Open
Abstract
Here, we report the coding-complete genome sequence of African swine fever (ASF) virus strain Liv13/33, isolated from experimentally infected pigs and Ornithodoros moubata ticks. The 11 sequences that we obtained harbored no notable differences to each other, and all of them were closely related to the genome sequence of the Mkuzi 1979 strain of genotype I.
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Affiliation(s)
- Amélie Chastagner
- Swine Virology and Immunology Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Rémi Pereira de Oliveira
- Swine Virology and Immunology Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
- UMR ASTRE, CIRAD, Montpellier, France
- UMR ASTRE, CIRAD, INRAE, University Montpellier, Montpellier, France
| | - Evelyne Hutet
- Swine Virology and Immunology Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Mireille Le Dimna
- Swine Virology and Immunology Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Frédéric Paboeuf
- SPF Pig Production and Experimentation Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Pierrick Lucas
- Viral Genetic and Biosecurity Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Yannick Blanchard
- Viral Genetic and Biosecurity Unit, ANSES Ploufragan-Plouzané-Niort Laboratory, Ploufragan, France
| | - Linda Dixon
- OIE Reference Laboratory, The Pirbright Institute, Surrey, United Kingdom
| | - Laurence Vial
- UMR ASTRE, CIRAD, Montpellier, France
- UMR ASTRE, CIRAD, INRAE, University Montpellier, Montpellier, France
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26
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O'Neill X, White A, Ruiz-Fons F, Gortázar C. Modelling the transmission and persistence of African swine fever in wild boar in contrasting European scenarios. Sci Rep 2020; 10:5895. [PMID: 32246098 PMCID: PMC7125206 DOI: 10.1038/s41598-020-62736-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/13/2020] [Indexed: 11/09/2022] Open
Abstract
African swine fever (ASF) is a severe viral disease that is currently spreading among domestic pigs and wild boar (Sus scrofa) in large areas of Eurasia. Wild boar play a key role in the spread of ASF, yet despite their significance, little is known about the key mechanisms that drive infection transmission and disease persistence. A mathematical model of the wild boar ASF system is developed that captures the observed drop in population density, the peak in infected density and the persistence of the virus observed in ASF outbreaks. The model results provide insight into the key processes that drive the ASF dynamics and show that environmental transmission is a key mechanism determining the severity of an infectious outbreak and that direct frequency dependent transmission and transmission from individuals that survive initial ASF infection but eventually succumb to the disease are key for the long-term persistence of the virus. By considering scenarios representative of Estonia and Spain we show that faster degradation of carcasses in Spain, due to elevated temperature and abundant obligate scavengers, may reduce the severity of the infectious outbreak. Our results also suggest that the higher underlying host density and longer breeding season associated with supplementary feeding leads to a more pronounced epidemic outbreak and persistence of the disease in the long-term. The model is used to assess disease control measures and suggests that a combination of culling and infected carcass removal is the most effective method to eradicate the virus without also eradicating the host population, and that early implementation of these control measures will reduce infection levels whilst maintaining a higher host population density and in some situations prevent ASF from establishing in a population.
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Affiliation(s)
- Xander O'Neill
- Maxwell Institute for Mathematical Sciences, Department of Mathematics, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Andy White
- Maxwell Institute for Mathematical Sciences, Department of Mathematics, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - Francisco Ruiz-Fons
- SaBio, Instituto de Investigación en Recursos Cinegéticos IREC (UCLM & CSIC), 13005, Ciudad Real, Spain
| | - Christian Gortázar
- SaBio, Instituto de Investigación en Recursos Cinegéticos IREC (UCLM & CSIC), 13005, Ciudad Real, Spain
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27
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African Swine Fever Outbreak at a Farm in Central Namibia. Case Rep Vet Med 2019; 2019:3619593. [PMID: 31772813 PMCID: PMC6854922 DOI: 10.1155/2019/3619593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 08/03/2019] [Accepted: 08/20/2019] [Indexed: 11/17/2022] Open
Abstract
An outbreak of African swine fever (ASF) occurred at a farm in central Namibia in March 2018. Fourteen pigs died out of a herd of 59 animals over a period of 16 days between the first and sixteenth of March 2018. The clinical signs observed included sternal recumbency, fever, weakness, pain and reluctance to move, hyperemia of the skin and anorexia, followed by death. Necropsy findings included large amounts of unclotted blood in the pleural and peritoneal cavities, diffuse carcass congestion, splenomegaly, consolidation of both lungs, hemorrhagic and frothy airways and trachea, hepatomegaly and congestion, congestion of the gastric mucosa, enlarged and congested kidneys, ecchymotic epicardial, and endocardial hemorrhages, and very enlarged and congested urinary bladder. All the remaining pigs were euthanized, burned, and buried under state veterinary supervision. The authors concluded that the outbreak resulted from indirect transmission of the ASF virus due to lapses in biosecurity measures.
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28
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Teklue T, Sun Y, Abid M, Luo Y, Qiu HJ. Current status and evolving approaches to African swine fever vaccine development. Transbound Emerg Dis 2019; 67:529-542. [PMID: 31538406 DOI: 10.1111/tbed.13364] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 08/22/2019] [Accepted: 09/09/2019] [Indexed: 12/21/2022]
Abstract
African swine fever (ASF) is a highly lethal haemorrhagic disease of swine caused by African swine fever virus (ASFV), a unique and genetically complex virus. The disease continues to be a huge burden to the pig industry in Africa, Europe and recently in Asia, especially China. The purpose of this review was to recapitulate the current scenarios and evolving trends in ASF vaccine development. The unavailability of an applicable ASF vaccine is partly due to the complex nature of the virus, which encodes various proteins associated with immune evasion. Moreover, the incomplete understanding of immune protection determinants of ASFV hampers the rational vaccine design. Developing an effective ASF vaccine continues to be a challenging task due to many undefined features of ASFV immunobiology. Recent attempts on DNA and live attenuated ASF vaccines have been reported with promising efficacy, and especially live attenuated vaccines have been proved to provide complete homologous protection. Single-cycle viral vaccines have been developed for various diseases such as Rift Valley fever and bluetongue, and the rational extension of these strategies could be helpful for developing single-cycle ASF vaccines. Therefore, live attenuated vaccines in short term and single-cycle vaccines in long term would be the next generation of ASF vaccines.
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Affiliation(s)
- Teshale Teklue
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.,Tigray Agricultural Research Institute, Mekelle, Ethiopia
| | - Yuan Sun
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Muhammad Abid
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yuzi Luo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Hua-Ji Qiu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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29
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Mulumba-Mfumu LK, Saegerman C, Dixon LK, Madimba KC, Kazadi E, Mukalakata NT, Oura CAL, Chenais E, Masembe C, Ståhl K, Thiry E, Penrith ML. African swine fever: Update on Eastern, Central and Southern Africa. Transbound Emerg Dis 2019; 66:1462-1480. [PMID: 30920725 DOI: 10.1111/tbed.13187] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 03/21/2019] [Accepted: 03/24/2019] [Indexed: 11/28/2022]
Abstract
Control of African swine fever (ASF) in countries in Eastern, Central and Southern Africa (ECSA) is particularly complex owing to the presence of all three known epidemiological cycles of maintenance of the virus, namely an ancient sylvatic cycle involving the natural hosts and vectors of the disease as well as domestic cycles with and without involvement of natural vectors. While the situation is well documented in some of the countries, for others very little information is available. In spite of the unfavourable ASF situation, the pig population in the sub-region has grown exponentially in recent decades and is likely to continue to grow in response to rapid urban growth resulting in increasing demand for animal protein by populations that are no longer engaged in livestock production. Better management of ASF will be essential to permit the pig sector to reach its full potential as a supplier of high quality protein and a source of income to improve livelihoods and create wealth. No vaccine is currently available and it is likely that, in the near future, the sub-region will continue to rely on the implementation of preventive measures, based on the epidemiology of the disease, to avoid both the devastating losses that outbreaks can cause and the risk the sub-region poses to other parts of Africa and the world. The current situation in the ECSA sub-region is reviewed and gaps in knowledge are identified in order to support ongoing strategy development for managing ASF in endemic areas.
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Affiliation(s)
- Léopold K Mulumba-Mfumu
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo.,Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR- ULiège), Fundamental and Applied Research for Animals & Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, Liege, Belgium
| | - Claude Saegerman
- Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR- ULiège), Fundamental and Applied Research for Animals & Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, Liege, Belgium
| | | | - Kapanga C Madimba
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Eric Kazadi
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Ndeji T Mukalakata
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Chris A L Oura
- School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, Champ Fleurs, Trinidad and Tobago
| | - Erika Chenais
- Department of Disease Control and Epidemiology, SVA, Uppsala, Sweden
| | - Charles Masembe
- College of Natural Sciences, Makerere University, Kampala, Uganda
| | - Karl Ståhl
- Department of Disease Control and Epidemiology, SVA, Uppsala, Sweden
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Fundamental and Applied Research for Animals & Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, Liege, Belgium
| | - Mary Louise Penrith
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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Penrith ML, Bastos AD, Etter EMC, Beltrán-Alcrudo D. Epidemiology of African swine fever in Africa today: Sylvatic cycle versus socio-economic imperatives. Transbound Emerg Dis 2019; 66:672-686. [PMID: 30633851 DOI: 10.1111/tbed.13117] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 12/04/2018] [Accepted: 12/14/2018] [Indexed: 11/29/2022]
Abstract
African swine fever (ASF) is believed to have evolved in eastern and southern Africa in a sylvatic cycle between common warthogs (Phacochoerus africanus) and argasid ticks of the Ornithodoros moubata complex that live in their burrows. The involvement of warthogs and possibly other wild suids in the maintenance of ASF virus means that the infection cannot be eradicated from Africa, but only prevented and controlled in domestic pig populations. Historically, outbreaks of ASF in domestic pigs in Africa were almost invariably linked to the presence of warthogs, but subsequent investigations of the disease in pigs revealed the presence of another cycle involving domestic pigs and ticks, with a third cycle becoming apparent when the disease expanded into West Africa where the sylvatic cycle is not present. The increase in ASF outbreaks that has accompanied the exponential growth of the African pig population over the last three decades has heralded a shift in the epidemiology of ASF in Africa, and the growing importance of the pig husbandry and trade in the maintenance and spread of ASF. This review, which focuses on the ASF situation between 1989 and 2017, suggests a minor role for wild suids compared with the domestic cycle, driven by socio-economic factors that determine the ability of producers to implement the control measures needed for better management of ASF in Africa.
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Affiliation(s)
- Mary-Louise Penrith
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | - Armanda Duarte Bastos
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Eric M C Etter
- Department of Production Animal Studies, University of Pretoria, Pretoria, South Africa.,CIRAD, UMR Animal Santé, Territoires, Risque et Ecosystèmes (ASTRE), Montpellier, France.,ASTRE, Univ. Montpellier, CIRAD, INRA, Montpellier, France
| | - Daniel Beltrán-Alcrudo
- Regional Office for Europe and Central Asia, Food and Agriculture Organization of the United Nations, Budapest, Hungary
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31
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Simulundu E, Sinkala Y, Chambaro HM, Chinyemba A, Banda F, Mooya LE, Ndebe J, Chitanga S, Makungu C, Munthali G, Fandamu P, Takada A, Mweene AS. Genetic characterisation of African swine fever virus from 2017 outbreaks in Zambia: Identification of p72 genotype II variants in domestic pigs. ACTA ACUST UNITED AC 2018; 85:e1-e5. [PMID: 30035596 PMCID: PMC6238689 DOI: 10.4102/ojvr.v85i1.1562] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 11/01/2022]
Abstract
African swine fever (ASF) is a contagious haemorrhagic disease associated with causing heavy economic losses to the swine industry in many African countries. In 2017, Zambia experienced ASF outbreaks in Mbala District (Northern province) and for the first time in Isoka and Chinsali districts (Muchinga province). Meanwhile, another outbreak was observed in Chipata District (Eastern province). Genetic analysis of part of the B646L gene, E183L gene, CP204L gene and the central variable region of the B602L gene of ASF virus (ASFV) associated with the outbreaks in Mbala and Chipata districts was conducted. The results revealed that the ASFV detected in Mbala District was highly similar to that of the Georgia 2007/1 isolate across all the genome regions analysed. In contrast, while showing close relationship with the Georgia 2007/1 virus in the B646L gene, the ASFV detected in Chipata District showed remarkable genetic variation in the rest of the genes analysed. These results suggest that the Georgia 2007/1-like virus could be more diverse than what was previously thought, underscoring the need of continued surveillance and monitoring of ASFVs within the south-eastern African region to better understand their epidemiology and the relationships between outbreaks and their possible origin.
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32
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Sargsyan MA, Voskanyan HE, Karalova EM, Hakobyan LH, Karalyan ZA. Third wave of African swine fever infection in Armenia: Virus demonstrates the reduction of pathogenicity. Vet World 2018; 11:5-9. [PMID: 29479149 PMCID: PMC5813512 DOI: 10.14202/vetworld.2018.5-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 12/05/2017] [Indexed: 11/16/2022] Open
Abstract
Aim: First cases of clinically uncommon African swine fever (ASF), caused by virus genotype II are described in this article. These cases occurred in Armenia, Tavush region, Dilijan municipality in 2011. The aim of this study was to identify and describe the new pathogenic forms of ASF in Armenia. Materials and Methods: The isolation and identification of ASF virus (ASFV) were carried out using conventional techniques. Clinical signs of infection were recorded daily. Gross anatomical pathology characteristics were observed during routine postmortem examinations. Blood and serum were obtained by puncture of the jugular vein using a vacutainer system. Results: The presence of ASFV DNA in the spleens was confirmed by polymerase chain reaction. Sequenced sections of p72 showed phylogenetic identity to genotype 2. The pathology exhibits unusual manifestations of the main disease. The unusual form of ASF demonstrates characteristics of a subacute form of the disease, with the possibility of conversion to a chronic form. Decreased lethality, low level of hemorrhages, and absence of severe pancytopenia in smears from spleen, lymph nodes, and blood are common features of the new form of ASF. Unlike severe thrombocytopenia in the typical ASF, the unusual form exhibited moderate or minor decrease of this feature. Despite a moderate decrease in hemadsorption titers, the unusual pattern of the disease was characterized by viremia and the presence of the virus in the visceral organs, including the brain. Conclusion: Our data allow assuming that new nosological form of ASF (genotype II) may present as a transitional form of the disease with the possibility of chronization.
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Affiliation(s)
- M A Sargsyan
- Department of Epizootiology and Parasitology, Armenian National Agrarian University, Yerevan 0009, Armenia
| | - H E Voskanyan
- Laboratory of Cell Biology and Virology, Institute of Molecular Biology of The National Academy of Sciences of the Republic of Armenia (NAS RA), 7 Hasratyan St., Yerevan 0014, Armenia
| | - E M Karalova
- Laboratory of Cell Biology and Virology, Institute of Molecular Biology of The National Academy of Sciences of the Republic of Armenia (NAS RA), 7 Hasratyan St., Yerevan 0014, Armenia
| | - L H Hakobyan
- Laboratory of Cell Biology and Virology, Institute of Molecular Biology of The National Academy of Sciences of the Republic of Armenia (NAS RA), 7 Hasratyan St., Yerevan 0014, Armenia
| | - Z A Karalyan
- Laboratory of Cell Biology and Virology, Institute of Molecular Biology of The National Academy of Sciences of the Republic of Armenia (NAS RA), 7 Hasratyan St., Yerevan 0014, Armenia.,Department of Biology, Yerevan State Medical University, Yerevan, Armenia
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