scholarly journals Tantangan dan Kendala Pengendalian African Swine Fever

2021 ◽  
Vol 39 (1) ◽  
pp. 62
Author(s):  
Roza Azizah Primatika ◽  
Etih Sudarnika ◽  
Bambang Sumiarto ◽  
Chaerul Basri

African Swine Fever (ASF) is a highly contagious hemorrhagic viral disease that attacks pigs and wild pigs causing economic losses for farms small and large scale. ASF outbreaks that occurred in several regions in the world have caused unrest for the livestock sector. The rapid spread of the ASF virus has resulted in very high pig mortality. ASF virus transmission can occur through direct or indirect contact. Urine and faecal excretion of pigs is an important route of ASF transmission. The ASF virus has three transmission cycles, namely the silvatic, domestic and wild boar cycles. Outbreaks that occur in several countries encourage the strategy of controlling and overcoming the disease through surveillance. ASF disease control that has been carried out includes improving farm biosecurity management systems and limiting the movement of animals and animal products before the ASF vaccine is found.

2020 ◽  
Author(s):  
zhenhua Guo ◽  
Kunpeng Li ◽  
Songlin Qiao ◽  
Xinxin Chen ◽  
Ruiguang Deng ◽  
...  

Abstract Background: African swine fever (ASF) is the most important disease to the pigs and cause serious economic losses to the countries with large-scale swine production. Vaccines are recognized as the most useful tool to prevent and control ASF virus (ASFV) infection. Currently, the MGF505 and MGF360 gene-deleted ASFVs or combined with CD2v deletion were confirmed to be the most promising vaccine candidates. Thus, it is essential to develop a diagnosis method to discriminate wide-type strain from the vaccines used.Results: In this study, we established a duplex TaqMan real-time PCR based on the B646L gene and MGF505-2R gene. The sequence alignment showed that the targeted regions of primers and probes are highly conserved in the genotype II ASFVs. The duplex real-time assay can specifically detect B646L and MGF505-2R gene single or simultaneously without cross-reaction with other porcine viruses tested. The limit of detection was 5.8 copies and 3.0 copies for the standard plasmids containing B646L and MGF505-2R genes, respectively. Clinical samples were tested in parallel by duplex real-time PCR and a commercial ASFV detection kit. The detection results of these two assays against B646L gene were well consistent.Conclusion: We successfully developed and evaluated a duplex TaqMan real-time PCR method which can effectively distinguish the wide type and MGF505 gene-deleted ASFVs. It would be a useful tool for the clinical diagnosis and control of ASF.


2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Zhenhua Guo ◽  
Kunpeng Li ◽  
Songlin Qiao ◽  
Xin-xin Chen ◽  
Ruiguang Deng ◽  
...  

Abstract Background African swine fever (ASF) is the most important disease to the pigs and cause serious economic losses to the countries with large-scale swine production. Vaccines are recognized as the most useful tool to prevent and control ASF virus (ASFV) infection. Currently, the MGF505 and MGF360 gene-deleted ASFVs or combined with CD2v deletion were confirmed to be the most promising vaccine candidates. Thus, it is essential to develop a diagnosis method to discriminate wide-type strain from the vaccines used. Results In this study, we established a duplex TaqMan real-time PCR based on the B646L gene and MGF505-2R gene. The sequence alignment showed that the targeted regions of primers and probes are highly conserved in the genotype II ASFVs. The duplex real-time assay can specifically detect B646L and MGF505-2R gene single or simultaneously without cross-reaction with other porcine viruses tested. The limit of detection was 5.8 copies and 3.0 copies for the standard plasmids containing B646L and MGF505-2R genes, respectively. Clinical samples were tested in parallel by duplex real-time PCR and a commercial ASFV detection kit. The detection results of these two assays against B646L gene were well consistent. Conclusion We successfully developed and evaluated a duplex TaqMan real-time PCR method which can effectively distinguish the wide type and MGF505 gene-deleted ASFVs. It would be a useful tool for the clinical diagnosis and control of ASF.


2020 ◽  
Author(s):  
Zhenhua Guo ◽  
Kunpeng Li ◽  
Songlin Qiao ◽  
Xinxin Chen ◽  
Ruiguang Deng ◽  
...  

Abstract Background: African swine fever (ASF) is the most important disease to the pigs and cause serious economic losses to the countries with large-scale swine production. Vaccines are recognized as the most useful tool to prevent and control ASF virus (ASFV) infection. Currently, the MGF505 and MGF360 gene-deleted ASFVs or combined with CD2v deletion were confirmed to be the most promising vaccine candidates. Thus, it is essential to develop a diagnosis method to discriminate wide-type strain from the vaccines used. Results: In this study, we established a duplex TaqMan real-time PCR based on the B646L gene and MGF505-2R gene. The sequence alignment showed that the targeted regions of primers and probes are highly conserved in the genotype II ASFVs. The duplex real-time assay can specifically detect B646L and MGF505-2R gene single or simultaneously without cross-reaction with other porcine viruses tested. The limit of detection was 5.8 copies and 3.0 copies for the standard plasmids containing B646L and MGF505-2R genes, respectively. Clinical samples were tested in parallel by duplex real-time PCR and a commercial ASFV detection kit. The detection results of these two assays against B646L gene were well consistent. Conclusion: We successfully developed and evaluated a duplex TaqMan real-time PCR method which can effectively distinguish the wide type and MGF505 gene-deleted ASFVs. It would be a useful tool for the clinical diagnosis and control of ASF.


2020 ◽  
Vol 94 (6) ◽  
Author(s):  
Qinghong Xue ◽  
Hongke Xu ◽  
Huaidong Liu ◽  
Jiaojiao Pan ◽  
Jiao Yang ◽  
...  

ABSTRACT Differentiating infected from vaccinated animals (DIVA) strategies have been central enabling techniques in several successful viral disease elimination programs. However, owing to their long and uncertain development process, no DIVA-compatible vaccines are available for many important diseases. We report herein a new DIVA strategy based on hybrid protein-peptide microarrays which can theoretically work with any vaccine. Leading from our findings from peste des petits ruminants (PPR) virus, we found 4 epitope-containing short peptides (ECSPs) which have distinct IgG serodynamics: anti-ECSP IgGs only exist for 10 to 60 days postvaccination (dpv), while anti-protein IgGs remained at high levels for >1,000 dpv. These data enabled the design of a DIVA diagnostic microarray containing 4 ECSPs and 3 proteins, which, unlike competitive enzyme-linked immunosorbent assay (cELISA) and virus neutralization tests (VNTs), enables ongoing monitoring of serological differences between vaccinated individuals and individuals exposed to the pathogen. For 25 goats after 60 dpv, 13 were detected with positive anti-ECSP IgGs, indicating recent infections in vaccinated goat herds. These DIVA diagnostic microarrays will almost certainly facilitate eradication programs for (re)emerging pathogens and zoonoses. IMPORTANCE Outbreaks of infectious diseases caused by viruses, such as pseudorabies (PR), foot-and-mouth disease (FMD), and PPR viruses, led to economic losses reaching billions of dollars. Both PR and FMD were eliminated in several countries via large-scale vaccination programs using DIVA-compatible vaccines, which lack the gE protein and nonstructural proteins, respectively. However, there are still extensive challenges facing the development and deployment of DIVA-compatible vaccines because they are time-consuming and full of uncertainty. Further, the negative marker strategy used for DIVA-compatible vaccines is no longer functional for live-attenuated vaccines. To avoid these disadvantageous scenarios, a new strategy is desired. Here, we made the exciting discovery that different IgG serodynamics can be monitored when using protein-based assays versus arrays comprising ECSPs. This DIVA microarray strategy should, in theory, work for any vaccine.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 190 ◽  
Author(s):  
Paula Rozo-Lopez ◽  
Barbara Drolet ◽  
Berlin Londoño-Renteria

Vesicular stomatitis (VS) is a viral disease of veterinary importance, enzootic in tropical and subtropical regions of the Americas. In the U.S., VS produces devastating economic losses, particularly in the southwestern states where the outbreaks display an occurrence pattern of 10-year intervals. To date, the mechanisms of the geographic spread and maintenance cycles during epizootics remain unclear. This is due, in part, to the fact that VS epidemiology has a complex of variables to consider, including a broad range of vertebrate hosts, multiple routes of transmission, and an extensive diversity of suspected vector species acting as both mechanical and biological vectors. Infection and viral progression within vector species are highly influenced by virus serotype, as well as environmental factors, including temperature and seasonality; however, the mechanisms of viral transmission, including non-conventional pathways, are yet to be fully studied. Here, we review VS epidemiology and transmission mechanisms, with comparisons of transmission evidence for the four most incriminated hematophagous dipteran taxa: Aedes mosquitoes, Lutzomyia sand flies, Simulium black flies, and Culicoides biting midges.


2015 ◽  
Vol 41 (02) ◽  
pp. 51-57
Author(s):  
Rabia Tahir ◽  
Aftab Ahmed Anjum ◽  
Khushi Muhammad ◽  
Asfa Rasool ◽  
Farah Khan

Avian influenza (AI) is a highly contagious and zoonotic viral disease that affects several animal species. It causes heavy economic losses in the domestic poultry. A quick response is always desired in the event of any disease outbreak. The principal approach to control a contagious disease involves the killing of diseased animals along with the bio containment of infectious agent. Mass depopulation of the infected birds plays an important role in the eradication of the disease. The possible strategies for mass depopulation include maceration, electrocution, cervical dislocation, gassing and foaming. All of these procedures are much intensive and time consuming because it involves a lot of man power, biosecurity risks, applicability for all house types and suitability for large-scale emergency implementation. The basic objectives of these strategies include (1) To reduce pain and suffering to the birds, (2) To minimize disease spread and (3) To ensure of protection to human operators from potential biohazards. A suitable depopulation technique can only be suggested keeping in view the species and type of bird involved, and differences in husbandry practices like management, housing and stocking density. Mass depopulation is an important tool to control the spread of any disease but the selection of procedure depends upon the prevailing circumstances. In this paper, various mass depopulation strategies and their selection in different conditions is reviewed and discussed.


2020 ◽  
Vol 8 (11) ◽  
pp. 1766
Author(s):  
Marie Cicille Ba Gahn ◽  
Fallou Niakh ◽  
Mamadou Ciss ◽  
Ismaila Seck ◽  
Modou Moustapha Lo ◽  
...  

Bluetongue is a non-contagious viral disease affecting small ruminants and cattle that can cause severe economic losses in the livestock sector. The virus is transmitted by certain species of the genus Culicoides and consequently, understanding their distribution is essential to enable the identification of high-risk transmission areas. In this work we use bioclimatic and environmental variables to predict vector abundance, and estimate spatial variations in the basic reproductive ratio  R0. The resulting estimates were combined with livestock mobility and serological data to assess the risk of Bluetongue outbreaks in Senegal. The results show an increasing abundance of C. imicola, C. oxystoma, C. enderleini, and C. miombo from north to south. R0 < 1 for most areas of Senegal, whilst southern (Casamance) and southeastern (Kedougou and part of Tambacounda) agro-pastoral areas have the highest risk of outbreak (R0 = 2.7 and 2.9, respectively). The next higher risk areas are in the Senegal River Valley (R0 = 1.07), and the Atlantic coast zones. Seroprevalence rates, shown by cELISA, weren’t positively correlated with outbreak probability. Future works should include follow-up studies of competent vector abundancies and serological surveys based on the results of the risk analysis conducted here to optimize the national epidemiological surveillance system.


Author(s):  
Sheree A Pagsuyoin ◽  
Joost R Santos

Water is a critical natural resource that sustains the productivity of many economic sectors, whether directly or indirectly. Climate change alongside rapid growth and development are a threat to water sustainability and regional productivity. In this paper, we develop an extension to the economic input-output model to assess the impact of water supply disruptions to regional economies. The model utilizes the inoperability variable, which measures the extent to which an infrastructure system or economic sector is unable to deliver its intended output. While the inoperability concept has been utilized in previous applications, this paper offers extensions that capture the time-varying nature of inoperability as the sectors recover from a disruptive event, such as drought. The model extension is capable of inserting inoperability adjustments within the drought timeline to capture time-varying likelihoods and severities, as well as the dependencies of various economic sectors on water. The model was applied to case studies of severe drought in two regions: (1) the state of Massachusetts (MA) and (2) the US National Capital Region (NCR). These regions were selected to contrast drought resilience between a mixed urban–rural region (MA) and a highly urban region (NCR). These regions also have comparable overall gross domestic products despite significant differences in the distribution and share of the economic sectors comprising each region. The results of the case studies indicate that in both regions, the utility and real estate sectors suffer the largest economic loss; nonetheless, results also identify region-specific sectors that incur significant losses. For the NCR, three sectors in the top 10 ranking of highest economic losses are government-related, whereas in the MA, four sectors in the top 10 are manufacturing sectors. Furthermore, the accommodation sector has also been included in the NCR case intuitively because of the high concentration of museums and famous landmarks. In contrast, the Wholesale Trade sector was among the sectors with the highest economic losses in the MA case study because of its large geographic size conducive for warehouses used as nodes for large-scale supply chain networks. Future modeling extensions could potentially include analysis of water demand and supply management strategies that can enhance regional resilience against droughts. Other regional case studies can also be pursued in future efforts to analyze various categories of drought severity beyond the case studies featured in this paper.


Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1916
Author(s):  
Sameh A. Abdelnour ◽  
Mahmoud Alagawany ◽  
Nesrein M. Hashem ◽  
Mayada R. Farag ◽  
Etab S. Alghamdi ◽  
...  

Nanotechnology is one of the major advanced technologies applied in different fields, including agriculture, livestock, medicine, and food sectors. Nanomaterials can help maintain the sustainability of the livestock sector through improving quantitative and qualitative production of safe, healthy, and functional animal products. Given the diverse nanotechnology applications in the animal nutrition field, the use of nanomaterials opens the horizon of opportunities for enhancing feed utilization and efficiency in animal production. Nanotechnology facilitates the development of nano vehicles for nutrients (including trace minerals), allowing efficient delivery to improve digestion and absorption for better nutrient metabolism and physiology. Nanominerals are interesting alternatives for inorganic and organic minerals for animals that can substantially enhance the bioavailability and reduce pollution. Nanominerals promote antioxidant activity, and improve growth performance, reproductive performance, immune response, intestinal health, and the nutritional value of animal products. Nanominerals are also helpful for improving assisted reproductive technologies (ART) outcomes by enriching media for cryopreservation of spermatozoa, oocytes, and embryos with antioxidant nanominerals. Despite the promising positive effects of nanominerals on animal performance and health, there are various challenges related to nanominerals, including their metabolism and fate in the animal’s body. Thus, the economic, legal, and ethical implications of nanomaterials must also be considered by the authority. This review highlights the benefits of including nanominerals (particularly nano-selenium and nano-zinc) in animal diets and/or cryopreservation media, focusing on modes of action, physiological effects, and the potential toxicity of their impact on human health.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1546
Author(s):  
Marta Budziszewska ◽  
Patryk Frąckowiak ◽  
Aleksandra Obrępalska-Stęplowska

Bradysia species, commonly known as fungus gnats, are ubiquitous in greenhouses, nurseries of horticultural plants, and commercial mushroom houses, causing significant economic losses. Moreover, the insects from the Bradysia genus have a well-documented role in plant pathogenic fungi transmission. Here, a study on the potential of Bradysia impatiens to acquire and transmit the peanut stunt virus (PSV) from plant to plant was undertaken. Four-day-old larvae of B. impatiens were exposed to PSV-P strain by feeding on virus-infected leaves of Nicotiana benthamiana and then transferred to healthy plants in laboratory conditions. Using the reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR (RT-qPCR), and digital droplet PCR (RT-ddPCR), the PSV RNAs in the larva, pupa, and imago of B. impatiens were detected and quantified. The presence of PSV genomic RNA strands as well as viral coat protein in N. benthamiana, on which the viruliferous larvae were feeding, was also confirmed at the molecular level, even though the characteristic symptoms of PSV infection were not observed. The results have shown that larvae of B. impatiens could acquire the virus and transmit it to healthy plants. Moreover, it has been proven that PSV might persist in the insect body transstadially. Although the molecular mechanisms of virion acquisition and retention during insect development need further studies, this is the first report on B. impatiens playing a potential role in plant virus transmission.


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