scholarly journals Development of Isothermal Recombinase Polymerase Amplification Assay for Rapid Detection of Porcine Circovirus Type 2

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Yang Yang ◽  
Xiaodong Qin ◽  
Yingjun Sun ◽  
Guozheng Cong ◽  
Yanmin Li ◽  
...  

Porcine circovirus virus type II (PCV2) is the etiology of postweaning multisystemic wasting syndrome (PMWS), porcine dermatitis, nephropathy syndrome (PDNS), and necrotizing pneumonia. Rapid diagnosis tool for detection of PCV2 plays an important role in the disease control and eradication program. Recombinase polymerase amplification (RPA) assays using a real-time fluorescent detection (PCV2 real-time RPA assay) and RPA combined with lateral flow dipstick (PCV2 RPA LFD assay) were developed targeting the PCV2 ORF2 gene. The results showed that the sensitivity of the PCV2 real-time RPA assay was 102copies per reaction within 20 min at 37°C and the PCV2 RPA LFD assay had a detection limit of 102copies per reaction in less than 20 min at 37°C. Both assays were highly specific for PCV2, with no cross-reactions with porcine circovirus virus type 1, foot-and-mouth disease virus, pseudorabies virus, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and classical swine fever virus. Therefore, the RPA assays provide a novel alternative for simple, sensitive, and specific identification of PCV2.

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Zicheng Ma ◽  
Mengda Liu ◽  
Zhaohu Liu ◽  
Fanliang Meng ◽  
Hongyu Wang ◽  
...  

Abstract Background Porcine circovirus type 2 (PCV2) is one of the crucial swine viral pathogens, caused porcine circovirus associated diseases (PCVAD). Shandong province is one of the most important pork producing areas and bears a considerable economic loss due to PCVAD. However, there is limited information on epidemiology and coinfection rate of PCV2 with other critical swine diseases in this area, such as porcine reproductive and respiratory syndrome virus (PRRSV), classical swine fever virus (CSFV), Pseudorabies virus (PRV), and porcine epidemic diarrhea virus (PEDV). Results Overall, 89.59% serum samples and 36.98% tissue samples were positive for PCV2 specified ELISA and PCR positive for PCV2, respectively. The coinfection rates of PCV2 with PRRSV, PRV, CSFV, and PEDV were 26.73%, 18.37%, 13.06%, and 3.47%, respectively. Moreover, genetic characteristic of PCV2 were analyzed based on the cap genes showing that PCV2d is the dominant sub-genotype circulating in the province. Conclusions Our findings reveal that PCV2d, as the dominant strain, is prevailing in pig farms in Shandong province at high levels. There was a high frequency of coinfection of PCV2 and PRRSV.


2018 ◽  
Vol 63 (No. 8) ◽  
pp. 358-366
Author(s):  
LL Zheng ◽  
XH Jin ◽  
FS Wei ◽  
CQ Wang ◽  
HY Chen ◽  
...  

Porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 can cause reproductive failure in pigs, and swine are often simultaneously infected by combinations of the three viruses. We here report the development of a SYBR Green I-based multiplex real time PCR assay for simultaneous detection of porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2. Three pairs of specific primers were designed for the porcine parvovirus-VP2, porcine pseudorabies virus-gH and porcine circovirus type 2-ORF2 genes. Viral genomes were identified based on their distinctive melting temperatures in singleplex PCR reactions. The melting temperature was 74.5 °C for the 313 bp amplicon of porcine parvovirus-VP2 gene, 87.5 °C for the 355 bp amplicon of porcine pseudorabies virus-gH gene and 80.5 °C for the 171 bp amplicon of the porcine circovirus type 2-ORF2 gene, respectively. The detection limit of the method ranged from 0.01–0.03 TCID<sub>50</sub>/ml for the three viruses. In addition, porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 viral loads were measured in 100 field samples, and the result showed that the concordance between real-time PCR and conventional PCR was 60.42%. The sensitivity and specificity of real-time PCR were 100% and 100%, while those of conventional PCR were 40.83% and 72.22%, respectively.


Viruses ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 185 ◽  
Author(s):  
Ting Ouyang ◽  
Xinwei Zhang ◽  
Xiaohua Liu ◽  
Linzhu Ren

Porcine circovirus 2 (PCV2) is the etiological agent that causes porcine circovirus diseases and porcine circovirus-associated diseases (PCVD/PCVAD), which are present in every major swine-producing country in the world. PCV2 infections may downregulate the host immune system and enhance the infection and replication of other pathogens. However, the exact mechanisms of PCVD/PCVAD are currently unknown. To date, many studies have reported that several cofactors, such as other swine viruses or bacteria, vaccination failure, and stress or crowding, in combination with PCV2, lead to PCVD/PCVAD. Among these cofactors, co-infection of PCV2 with other viruses, such as porcine reproductive and respiratory syndrome virus, porcine parvovirus, swine influenza virus and classical swine fever virus have been widely studied for decades. In this review, we focus on the current state of knowledge regarding swine co-infection with different PCV2 genotypes or strains, as well as with PCV2 and other swine viruses.


Pathogens ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 279
Author(s):  
Muhammad Abid ◽  
Teshale Teklue ◽  
Yongfeng Li ◽  
Hongxia Wu ◽  
Tao Wang ◽  
...  

Pseudorabies (PR), classical swine fever (CSF), and porcine circovirus type 2 (PCV2)-associated disease (PCVAD) are economically important infectious diseases of pigs. Co-infections of these diseases often occur in the field, posing significant threat to the swine industry worldwide. gE/gI/TK-gene-deleted vaccines are safe and capable of providing full protection against PR. Classical swine fever virus (CSFV) E2 glycoprotein is mainly used in the development of CSF vaccines. PCV2 capsid (Cap) protein is the major antigen targeted for developing PCV2 subunit vaccines. Multivalent vaccines, and especially virus-vectored vaccines expressing foreign proteins, are attractive strategies to fight co-infections for various swine diseases. The gene-deleted pseudorabies virus (PRV) can be used to develop promising and economical multivalent live virus-vectored vaccines. Herein, we constructed a gE/gI/TK-gene-deleted PRV co-expressing E2 of CSFV and Cap of PCV2 by fosmid library platform established for PRV, and the expression of E2 and Cap proteins was confirmed using immunofluorescence assay and western blotting. The recombinant virus propagated in porcine kidney 15 (PK-15) cells for 20 passages was genetically stable. The evaluation results in rabbits and pigs demonstrate that rPRVTJ-delgE/gI/TK-E2-Cap elicited detectable anti-PRV antibodies, but not anti-PCV2 or anti-CSFV antibodies. These findings provide insights that rPRVTJ-delgE/gI/TK-E2-Cap needs to be optimally engineered as a promising trivalent vaccine candidate against PRV, PCV2 and CSFV co-infections in future.


2019 ◽  
Author(s):  
Han Zhou ◽  
Yan Pan ◽  
Mengda Liu ◽  
Zifeng Han

Abstract Background Pseudorabies (PR) is a highly contagious disease affecting a wide range of animals worldwide, which causes great annual economic losses in China. In this study, a total number of 18815 serum samples and 1589 tissue samples were tested by ELISA and PCR, which were collected from 311 intensive pig farms (≥350 sows) located in eight cities in Heilongjiang province. Results Overall, 16.3% and 84.5% serum samples were positive for gE- and gB-specified ELISA, respectively. 17.8% of tissue samples were shown as PCR positive for PRV. The co-infection rates of PRV with porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), and classical swine fever virus (CSFV) were measured. The rate of PRV co-infected with PRRSV was 36.0% followed by 12.9% with PCV2 and 1.8% with CSFV, respectively. Conclusions These results clearly demonstrate PRV prevalence and its coinfection rate in Heilongjiang province indicating high PR endemic in pig farms in this region. This study provides data for further epidemiological investigations and a reference for developing PRV control strategies in this region and in China.


Sign in / Sign up

Export Citation Format

Share Document