scholarly journals Recent Advances in Porcine Reproductive and Respiratory Syndrome Virus NADC30-Like Research in China: Molecular Characterization, Pathogenicity, and Control

2022 ◽  
Vol 12 ◽  
Author(s):  
Ying Yu ◽  
Qiaoya Zhang ◽  
Zhi Cao ◽  
Yan-Dong Tang ◽  
Dasong Xia ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Production Systems ◽  
Respiratory Syndrome Virus ◽  
Swine Production ◽  
Swine Industry ◽  
Live Virus ◽  
Major Health ◽  
Swine Farms ◽  
Protection Efficacy ◽  
And Control

The name porcine reproductive and respiratory syndrome virus (PRRSV) NADC30-like was first coined in 2015. It originated from the NADC30 strain that was introduced into China by importing breeding pigs and has since undergone mutations or recombination, resulting in variant viruses. Following widespread outbreaks in China in recent years, these NADC30-like strains have presented major health challenges in swine production systems. Outcomes induced by PRRSV NADC30-like infection are highly variable, ranging from inapparent to severe, depending on the recombination between NADC30 and field PRRSV strains prevalent in swine farms. Vaccines and strict biosecurity measures have been explored to fight this disease; however, current PRRSV commercially modified-live virus vaccines (MLVs) have the potential to revert to virulence and only provide limited or no cross-protection efficacy against NADC30-like strains. PRRSVs will remain an ongoing challenge to the swine industry until safe and effective vaccines or antiviral reagents are developed.

scholarly journals Structural comparison of CD163 SRCR5 from different species sheds some light on its involvement in porcine reproductive and respiratory syndrome virus-2 infection in vitro

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Hongfang Ma ◽  
Rui Li ◽  
Longguang Jiang ◽  
Songlin Qiao ◽  
Xin-xin Chen ◽  
...  
Keyword(s):  
Scavenger Receptor ◽  
Host Cells ◽  
Respiratory Syndrome Virus ◽  
Swine Industry ◽  
Prrs Virus ◽  
Rich Domain ◽  
Serious Disease ◽  
The One ◽  
And Control

AbstractPorcine reproductive and respiratory syndrome (PRRS) is a serious disease burdening global swine industry. Infection by its etiological agent, PRRS virus (PRRSV), shows a highly restricted tropism of host cells and has been demonstrated to be mediated by an essential scavenger receptor (SR) CD163. CD163 fifth SR cysteine-rich domain (SRCR5) is further proven to play a crucial role during viral infection. Despite intense research, the involvement of CD163 SRCR5 in PRRSV infection remains to be elucidated. In the current study, we prepared recombinant monkey CD163 (moCD163) SRCR5 and human CD163-like homolog (hCD163L1) SRCR8, and determined their crystal structures. After comparison with the previously reported crystal structure of porcine CD163 (pCD163) SRCR5, these structures showed almost identical structural folds but significantly different surface electrostatic potentials. Based on these differences, we carried out mutational research to identify that the charged residue at position 534 in association with the one at position 561 were important for PRRSV-2 infection in vitro. Altogether the current work sheds some light on CD163-mediated PRRSV-2 infection and deepens our understanding of the viral pathogenesis, which will provide clues for prevention and control of PRRS.

scholarly journals The Function of the PRRSV–Host Interactions and Their Effects on Viral Replication and Propagation in Antiviral Strategies

Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 364
Author(s):  
Jun Ma ◽  
Lulu Ma ◽  
Meiting Yang ◽  
Wei Wu ◽  
Wenhai Feng ◽  
...  
Keyword(s):  
Immune Response ◽  
Molecular Mechanisms ◽  
Immune Escape ◽  
Rna Virus ◽  
Economic Losses ◽  
Respiratory Syndrome Virus ◽  
Swine Industry ◽  
Live Virus ◽  
Virus Challenge ◽  
Host Interactions

Porcine reproductive and respiratory syndrome virus (PRRSV) affects the global swine industry and causes disastrous economic losses each year. The genome of PRRSV is an enveloped single-stranded positive-sense RNA of approximately 15 kb. The PRRSV replicates primarily in alveolar macrophages of pig lungs and lymphatic organs and causes reproductive problems in sows and respiratory symptoms in piglets. To date, studies on how PRRSV survives in the host, the host immune response against viral infections, and pathogenesis, have been reported. PRRSV vaccines have been developed, including inactive virus, modified live virus, attenuated live vaccine, DNA vaccine, and immune adjuvant vaccines. However, there are certain problems with the durability and effectiveness of the licensed vaccines. Moreover, the high variability and fast-evolving populations of this RNA virus challenge the design of PRRSV vaccines, and thus effective vaccines against PRRSV have not been developed successfully. As is well known, viruses interact with the host to escape the host’s immune response and then replicate and propagate in the host, which is the key to virus survival. Here, we review the complex network and the mechanism of PRRSV–host interactions in the processes of virus infection. It is critical to develop novel antiviral strategies against PRRSV by studying these host–virus interactions and structures to better understand the molecular mechanisms of PRRSV immune escape.

scholarly journals Dynamics of Virus Distribution in a Defined Swine Production Network Using Enteric Viruses as Molecular Markers

2016 ◽  
Vol 83 (4) ◽  
Author(s):  
Virginie Lachapelle ◽  
Ann Letellier ◽  
Philippe Fravalo ◽  
Julie Brassard ◽  
Yvan L'Homme
Keyword(s):  
Potential Role ◽  
Production Systems ◽  
Dynamic Networks ◽  
Enteric Viruses ◽  
Production Network ◽  
Swine Production ◽  
Swine Industry ◽  
Interconnected System ◽  
Diarrhea Virus

ABSTRACT Modern swine production systems represent complex and dynamic networks involving numerous stakeholders. For instance, livestock transporters carry live animals between fattening sites, abattoirs, and other premises on a daily basis. This interconnected system may increase the risk of microbial spread within and between networks, although little information is available in that regard. In the present study, a swine network composed of 10 finishing farms, one abattoir, and three types of stakeholders (veterinarians, livestock transporters, and nutritional technicians) in Quebec, Canada, was selected to investigate specific vectors and reservoirs of enteric viruses. Environmental samples were collected from the premises over a 12-month period. Samples were screened using targeted reverse transcription-PCR and sequencing of two selected viral markers, group A rotaviruses (RVA) and porcine astroviruses (PoAstV), both prevalent and genetically heterogeneous swine enteric viruses. The results revealed frequent contamination of farm sites (21.4 to 100%), livestock transporter vehicles (30.6 to 68.8%) and, most importantly, the abattoir yard (46.7 to 94.1%), depending on the sample types. Although high levels of strain diversity for both viruses were found, identical PoAstV and RVA strains were detected in specific samples from farms, the abattoir yard, and the livestock transporter vehicle, suggesting interconnections between these premises and transporters. Overall, the results from this study underscore the potential role of abattoirs and livestock transport as a reservoir and transmission route for enteric viruses within and between animal production networks, respectively. IMPORTANCE Using rotaviruses and astroviruses as markers of enteric contamination in a swine network has revealed the potential role of abattoirs and livestock transporters as a reservoir and vectors of enteric pathogens. The results from this study highlight the importance of tightening biosecurity measures. For instance, implementing sanitary vacancy between animal batches and emphasizing washing, disinfection, and drying procedures on farms and for transportation vehicles, as well as giving limited access and circulation of vehicles throughout the production premises, are some examples of measures that should be applied properly. The results also emphasize the need to closely monitor the dynamics of enteric contamination in the swine industry in order to better understand and potentially prevent the spread of infectious diseases. This is especially relevant when a virulent and economically damaging agent is involved, as seen with the recent introduction of the porcine epidemic diarrhea virus in the country.

scholarly journals Porcine reproductive and respiratory syndrome virus dissemination across pig production systems in the United States

2020 ◽  
Author(s):  
Manuel Jara ◽  
David A. Rasmussen ◽  
Cesar A. Corzo ◽  
Gustavo Machado
Keyword(s):  
Prevention And Control ◽  
Production Systems ◽  
The United States ◽  
Respiratory Syndrome Virus ◽  
Pig Production ◽  
The North ◽  
Relative Contribution ◽  
Virus Dissemination ◽  
Pig Farms ◽  
And Control

SummaryPorcine reproductive and respiratory syndrome virus (PRRSV) remains widespread in the North American pig population. Despite improvements in virus characterization, it is unclear whether PRRSV infections are a product of viral circulation within a farm, within production systems (local) or across production systems (external). Here we examined the dissemination dynamics of PRRSV and the processes facilitating its spread within and among pig farms in three production systems. Overall, PRRSV genetic diversity declined since 2018, while phylodynamic results support frequent transmission across-production systems. We found that PRRSV dissemination occurred mostly through transmission between farms of different production companies, which were predominant for several months, especially from November until May when PRRSV tends to peak in the studied region. Within production systems, dissemination occurred mainly through regular pig flow (from sow to nursery and then to finisher farms); nevertheless, an important flux of PRRSV dissemination from finisher to sow and nursery farms highlighted the importance of downstream farms as sources of the virus. Farms at areas with pig density from 500 to 1000 pig/km2 and farms located at a range within 0.5 km and 0.7 km from major roads were more likely to infect by PRRSV, whereas farms at elevation between 41 and 61 meters and denser vegetation acted as dissemination barriers. Although remains a challenge, there is a need to disentangle the route of PRRSV transmission, results evidenced that dissemination among commercially unrelated pig production systems was intense, reinforcing the importance of farm proximity on PRRSV spread. Thus, consideration of farm location and their geographic characteristics may help to forecast dissemination. The understanding of PRRSV transmission routes has the potential to inform targeted strategies for its prevention and control. Further studies are needed to quantify the relative contribution of PRRSV transmission routes.

scholarly journals Challenges for Porcine Reproductive and Respiratory Syndrome (PRRS) Vaccine Design: Reviewing Virus Glycoprotein Interactions with CD163 and Targets of Virus Neutralization

2019 ◽  
Vol 6 (1) ◽  
pp. 9 ◽  
Author(s):  
Ana Stoian ◽  
Raymond Rowland
Keyword(s):  
Vaccine Development ◽  
Noncovalent Interactions ◽  
Rna Virus ◽  
Neutralizing Antibody ◽  
Complex Surface ◽  
Surface Proteins ◽  
Respiratory Syndrome Virus ◽  
Swine Industry ◽  
Live Virus ◽  
Potential Vaccine

One of the main participants associated with the onset and maintenance of the porcine respiratory disease complex (PRDC) syndrome is porcine reproductive and respiratory syndrome virus (PRRSV), an RNA virus that has plagued the swine industry for 30 years. The development of effective PRRS vaccines, which deviate from live virus designs, would be an important step towards the control of PRRS. Potential vaccine antigens are found in the five surface proteins of the virus, which form covalent and multiple noncovalent interactions and possess hypervariable epitopes. Consequences of this complex surface structure include antigenic variability and escape from immunity, thus presenting challenges in the development of new vaccines capable of generating broadly sterilizing immunity. One potential vaccine target is the induction of antibody that disrupts the interaction between the macrophage CD163 receptor and the GP2, GP3, and GP4 heterotrimer that protrudes from the surface of the virion. Studies to understand this interaction by mapping mutations that appear following the escape of virus from neutralizing antibody identify the ectodomain regions of GP5 and M as important immune sites. As a target for antibody, GP5 possesses a conserved epitope flanked by N-glycosylation sites and hypervariable regions, a pattern of conserved epitopes shared by other viruses. Resolving this apparent conundrum is needed to advance PRRS vaccine development.

scholarly journals Efficacy of a Modified Live Virus Vaccine against Porcine Reproductive and Respiratory Syndrome Virus 1 (PRRSV-1) Administered to 1-Day-Old Piglets in Front of Heterologous PRRSV-1 Challenge

Pathogens ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1342
Author(s):  
Heinrich Kreutzmann ◽  
Sophie Dürlinger ◽  
Christian Knecht ◽  
Michaela Koch ◽  
Marta Cabana ◽  
...  
Keyword(s):  
Field Isolate ◽  
Daily Weight Gain ◽  
Respiratory Syndrome Virus ◽  
Average Daily Weight Gain ◽  
Swine Industry ◽  
Live Virus ◽  
Live Virus Vaccine ◽  
Nasal Swabs ◽  
Ifn Γ ◽  
The Impact

PRRSV is one of the most important viruses in the global swine industry and is often controlled by the use of modified live virus (MLV) vaccines. This study assessed the impact of a PRRSV-1 MLV vaccine applied to 1-day-old piglets challenged on day 28 of life with a PRRSV-1 field isolate (AUT15-33). Twenty-one piglets were vaccinated within 24 h of birth (T02), whereas 20 piglets were left unvaccinated (T01). Necropsy was performed two weeks post-challenge. Comparing the two groups, T02 piglets showed significantly higher (p = 0.017) average daily weight gain. In addition, significantly lower (p < 0.0001) PRRSV RNA loads were measured in serum of T02 piglets at all investigated time points. All T01 piglets were viremic and shed virus in nasal swabs, whereas only 71.4 % and 38.1 % of the T02 group were viremic or shed virus, respectively. Piglets from T02 had significantly higher numbers (p < 0.0001) of IFN-γ producing lymphocytes compared to T01. At necropsy, differences in gross and histologic lung lesions were statistically significant (p = 0.012 and p < 0.0001, respectively) between the two groups. Hence, this MLV vaccine administered to 1-day-old piglets was able to protect piglets against PRRSV infection at weaning.

scholarly journals Performance of assays for testing antibodies against porcine reproductive and respiratory syndrome virus in sera collected from swine farms in a region with an extreme virus heterogeneity

2014 ◽  
Vol 64 (1) ◽  
pp. 44-51 ◽  
Author(s):  
Uladzimir Karniychuk U ◽  
Hans Nauwynck J
Keyword(s):  
North American ◽  
Viral Disease ◽  
Respiratory Syndrome Virus ◽  
Test Field ◽  
Sample Collection ◽  
Swine Industry ◽  
East European ◽  
Swine Farms ◽  
The North ◽  
European Subtype

Abstract Porcine reproductive and respiratory syndrome is the most economically important viral disease in the swine industry worldwide. Porcine reproductive and respiratory syndrome virus (PRRSV) strains are classified into two distinct genotypes, the European genotype and the North American genotype. The European PRRSV genotype has been divided into three subtypes: a pan-European subtype 1 and East European subtypes 2 and 3. The aim of this study was to evaluate the performance of commercial and homemade serological assays to test field sera from a geographical region with an extreme PRRSV heterogeneity. Belarus became the country of choice for sample collection because heterologous PRRSV strains of all known European subtypes circulate in this country. Sera from Belarusian swine farms were tested in immunoperoxidase monolayer assays based on pan-European subtype 1, East European subtype 3 and North American strains as antigens and commercial enzyme-linked immunosorbent assays (IDEXX and INGEZIM). The obtained results suggest that none of the serological tools for PRRSV diagnosis can guarantee a flawless detection of antibodies at the individual animal level. Considering heterogeneity of recently isolated European PRRSV strains the problem can be relevant in many countries.

scholarly journals Pathogenic Characterization of European Genotype Porcine Reproductive and Respiratory Syndrome Virus Recently Isolated in Mainland China

2017 ◽  
Vol 11 (1) ◽  
pp. 83-89 ◽  
Author(s):  
Sun Ming ◽  
Ma Yongying ◽  
Liu Bohua ◽  
Lu Huiying ◽  
Deng Xiaoyu ◽  
...  
Keyword(s):  
Mainland China ◽  
Economic Loss ◽  
Respiratory Syndrome Virus ◽  
Type I ◽  
Swine Industry ◽  
Virulent Type ◽  
Prrsv Strain ◽  
European Genotype ◽  
And Control

Background:Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen in pig that causes tremendous economic loss in the global swine industry. PRRSV is divided into the European and North American genotypes, with virulence ranging from apathogenic-moderately virulent to highly pathogenic. The emergence of new highly virulent type 1 strains and coexistence of the two genotypes complicate the differential diagnosis, disease prevention, and control of PRRSV. Although the emergence of a novel type 1 PRRSV strain in mainland China was first confirmed in 2011, there is no information available concerning the pathogenesis of this strain.Objectives:We sought to determine the pathogenesis of a newly emerged Chinese type 1 PRRSV strain HLJB1.Methods:Pigs were infected with HLJB1 and characterized using serological and histopathological tests.Results:HLJB1 infection induced transient chemosis, reddened conjunctiva, skin cyanosis, mild transient pyrexia, dyspnea, and tachypnea between 7 and 13 days post-infection. Gross pneumonic lesions were characterized by multifocal, tan-mottled areas. Lymph nodes and spleen were enlarged. Characteristic microscopic lesions consisted of pulmonary consolidation and alveolar septal thickening with red blood cell infiltration, depletion of splenic lymphocytes, and hyperplasia and activation of macrophage. No pigs infected with HLJB1 died during the experiment.Conclusion:Our findings indicate that Chinese type I PRRSV strain HLJB1 caused classic PRRSV-specific lesions. As it caused lower viremia in pigs compared with other classic type 1 isolates, HLJB1 is less virulent than other type I strains.

scholarly journals PSVIII-1 A transcriptomic study of the effect of PRRSV infection during gestation on the piglet amygdala

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 255-256
Author(s):  
Marissa R Keever ◽  
Pan Zhang ◽  
Courtni R Bolt ◽  
Haley E Rymut ◽  
Adrienne M Antonson ◽  
...  
Keyword(s):  
Feed Efficiency ◽  
Management Practices ◽  
Transmembrane Protein ◽  
Respiratory Syndrome Virus ◽  
Neural Pathways ◽  
Molecular Processes ◽  
Long Term Effects ◽  
Swine Industry ◽  
And Control

Abstract Porcine reproductive and respiratory syndrome virus (PRRSV) is an economic burden on the swine industry, resulting in losses not only related to animal death but also to reduced offspring productivity. Understanding the underlying molecular pathways that contribute to decreased feed efficiency and behaviors that result in poorer performance is important for the implementation of management practices that aim to mitigate the effects of PRRSV. To uncover the long-term effects of PRRSV infection during gestation, a transcriptome analysis of the amygdala of 22-day-old piglet offspring from maternal PRRSV activated and control gilts was undertaken. Overall, 161 genes were differentially expressed between the PRRSV and control piglet offspring. Many of the genes were over-expressed in pigs from PRRSV compared to control gilts, such as interferon induced transmembrane protein 3 and neuron derived neurotrophic factor. Few genes were under-expressed, including insulin-like growth factor 2 and aldehyde dehydrogenase 1 family member A1. The detection of these dysregulated genes and the directionality of their differential expression yielded insights into the effects that maternal PRRSV infection has on the neural pathways of the offspring amygdala. This furthers our understanding of molecular processes underlying pathological behaviors that may be exhibited by these pigs, affecting management and production. This study is supported by USDA NIFA AFRI, grant number 2018-67015-27413.

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