The impact of porcine circovirus associated diseases on live attenuated classical swine fever vaccine in field farm applications

Chen, Jingyuan; Wu, Cheng-Shong; Liao, Chih-Ming; Chen, Kun-Chao; You, Chia-Chin; Wang, Yuwen; Huang, Chi‐Hsiang; Chien, Maw-Sheng

doi:10.1016/j.vaccine.2019.08.039

Cited by 9 publications

(10 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In practical applications, this conclusion must be established on the premise that, after unification with the PCV2 subunit vaccine, the viral load of PCV2 in individuals can be suppressed to subthreshold levels, with the minimum infectious virus dose for transmission and dissemination not attained. However, low PCV2 viral loads could still be detected in pig serum after immunization with the PCV2 subunit vaccine [39], indicating that the PCV2 vaccine based on current research cannot achieve this. Thus, under the current vaccine immunization effect, the method that we established may encounter certain obstacles in practical application.…”

Section: Discussionmentioning

confidence: 89%

Establishment of a Rep′ protein antibody detection method to distinguish natural infection with PCV2 from subunit vaccine immunization

Chen

Jin

et al. 2020

Journal of Medical Microbiology

View full text Add to dashboard Cite

Introduction. PCV2 is a DNA virus that exists widely in pigs and has caused great economic losses to the pig industry worldwide. In the existing commercial PCV2 enzyme-linked immunosorbent assay (ELISA) kits both natural infection with PCV2 and vaccine immunization produce results that are positive for PCV2 Cap antibodies and therefore they cannot diagnose PCV2 infection in immunized pig farms. Aim. To establish a PCV2 non-structural protein antibody detection method that distinguishes between antibodies resulting from natural prior exposure (infection) and those induced by subunit vaccine immunization. Methodology. Based on the non-structural Rep′ protein, we established an indirect ELISA (iELISA) using sera from guinea pigs and piglets. Results. The results for iELISA for guinea pig serum showed that animals vaccinated with a whole-virus inactivated PCV2 vaccine had 100 % (10/10) Cap antibody positivity and 100 % (10/10) Rep′ antibody positivity. Guinea pigs vaccinated with a recombinant subunit PCV2 vaccine had 100 % (10/10) Cap antibody positivity, while no (0/10) guinea pigs were Rep′ antibody-positive. The combined detection results for the Rep′ iELISA and a PCV2 Antibody Test kit (Commercial) showed that pigs vaccinated with a whole-virus inactivated PCV2 vaccine or PCV2 SD/2017 had 100 % (5/5) Cap antibody positivity and 100 % (5/5) Rep′ antibody positivity. Pigs vaccinated with a recombinant subunit PCV2 vaccine had 100 % (5/5) Cap antibody positivity, while no (0/10) pigs were Rep′ antibody-positive. Conclusion. This paper describes an effective iELISA method that can distinguish natural infection with PCV2 (Cap and Rep positive) or inoculation with a whole-virus inactivated vaccine (Cap and Rep positive) from subunit vaccine immunization (Cap-positive, Rep-negative). These comparative assays could be very useful in the control of PCV2 in pig herds.

show abstract

Section: Discussionmentioning

confidence: 89%

Establishment of a Rep′ protein antibody detection method to distinguish natural infection with PCV2 from subunit vaccine immunization

Chen

Jin

et al. 2020

Journal of Medical Microbiology

View full text Add to dashboard Cite

show abstract

“…Our results showed that the lowest level of CSFV antibody in piglets was found at 5–8 weeks of age in the MLV group ( Figure 1 ), which suggests a time window that may be appropriate for CSFV vaccination. In addition to MDA, several other immunosuppressive viruses, such as PRRSV [ 29 , 30 , 31 ], PCV2 [ 34 , 35 , 36 ] and pseudorabies virus [ 37 ], can potentially interfere with the efficacy of the CSFV MLV vaccine.…”

Section: Discussionmentioning

confidence: 99%

Serodynamic Analysis of the Piglets Born from Sows Vaccinated with Modified Live Vaccine or E2 Subunit Vaccine for Classical Swine Fever

Chiou

Lin

2020

Pathogens

View full text Add to dashboard Cite

Classical swine fever (CSF) caused by the CSF virus (CSFV) is one of the most important swine diseases, resulting in huge economic losses to the pig industry worldwide. Systematic vaccination is one of the most effective strategies for the prevention and control of this disease. Two main CSFV vaccines, the modified live vaccine (MLV) and the subunit E2 vaccine, are recommended. In Taiwan, CSF cases have not been reported since 2006, although systemic vaccination has been practiced for 70 years. Here, we examined the sero-dynamics of the piglets born from sows that received either the CSFV MLV or the E2 vaccine and investigated in the field the correlation between the porcine reproductive and respiratory syndrome virus (PRRSV) loads and levels of CSFV antibody. A total of 1398 serum samples from 42 PRRSV-positive farms were evaluated to determine the PRRSV loads by real-time PCR and to detect CSFV antibody levels by commercial ELISA. Upon comparing the two sow vaccination protocols (CSFV MLV vaccination at 4 weeks post-farrowing versus E2 vaccination at 4–5 weeks pre-farrowing), the lowest levels of CSFV antibody were found in piglets at 5–8 and 9–12 weeks of age for the MLV and E2 groups, respectively. Meanwhile, the appropriate time window for CSFV vaccination of offspring was at 5–8 and 9–12 weeks of age in the MLV and E2 groups, respectively. There was a very highly significant negative correlation between the PRRSV load and the level of CSFV antibody in the CSFV MLV vaccination group (P < 0.0001). The PRRSV detection rate in the pigs from the MLV group (27.78%) was significantly higher than that in pigs from the E2 group (21.32%) (P = 0.011). In addition, there was a significant difference (P = 0.019) in the PRRSV detection rate at 5–8 weeks of age between the MLV (42.15%) and E2 groups (29.79%). Our findings indicate that the vaccination of CSFV MLV in piglets during the PRRSV susceptibility period at 5–8 weeks of age may be overloading the piglet’s immune system and should be a critical concern for industrial pork production in the field.

show abstract

“…Although the development of vaccines has played an important role in preventing and controlling CSF or PCVD, the co-infection or superinfection of CSFV and PCV has evidently increased difficulties in the prevention and control of diseases in the pig breeding industry in recent years ( Ouyang et al, 2019 ). Some researchers have found that PCV2 could disturb the immune effect of the CSFV MLV vaccine ( Huang et al, 2014 ; Chen et al, 2019 ). Besides, the protection efficacy of the CSFV LOM vaccine could also be affected by the infection of PCV2 ( Lim et al, 2016 ).…”

Section: Introductionmentioning

confidence: 99%

Production and immunogenicity of a deoxyribonucleic acid Alphavirus vaccine expressing classical swine fever virus E2-Erns protein and porcine Circovirus Cap-Rep protein

Zhi²,

Ye³

et al. 2022

Front. Microbiol.

View full text Add to dashboard Cite

Classical swine fever virus (CSFV) and porcine Circovirus type 2 (PCV2) are economically pivotal infectious disease viruses of swine. Alphaviral RNA replicon plasmids have been used as an important vector for constructing nucleic acid vaccines. Here, we aimed to construct a recombinant alphaviral plasmid vaccine pSCA1-E2-Erns-Cap-Rep for the prevention and control of CSFV and PCV2. Our results showed that the recombinant alphaviral plasmid vaccine pSCA1-E2-Erns-Cap-Rep was successfully constructed. The vaccine encoding E2 and Erns of CSFV, Cap, and Rep of PCV2 can induce E2, Erns, Cap, and Rep protein expression. ELISA analysis showed that mice-immunized pSCA1-E2-Erns-Cap-Rep plasmid vaccine produced higher anti–CSFV- and anti–PCV2-specific antibodies with dose- and time-dependent manners. Furthermore, neutralizing assays were measured using IF and ELISA methods. The results showed the production of neutralizing antibodies could neutralize CSFV (up to 210.13) and PCV2 (28.6) effectively, which exhibited the immune efficacy of the pSCA1-E2-Erns-Cap-Rep plasmid vaccine. Taken together, this pSCA1-E2-Erns-Cp-Rep plasmid vaccine could be considered a novel candidate vaccine against CSFV and PCV2.

show abstract

The impact of porcine circovirus associated diseases on live attenuated classical swine fever vaccine in field farm applications

Cited by 9 publications

References 40 publications

Establishment of a Rep′ protein antibody detection method to distinguish natural infection with PCV2 from subunit vaccine immunization

Establishment of a Rep′ protein antibody detection method to distinguish natural infection with PCV2 from subunit vaccine immunization

Serodynamic Analysis of the Piglets Born from Sows Vaccinated with Modified Live Vaccine or E2 Subunit Vaccine for Classical Swine Fever

Production and immunogenicity of a deoxyribonucleic acid Alphavirus vaccine expressing classical swine fever virus E2-Erns protein and porcine Circovirus Cap-Rep protein

Contact Info

Product

Resources

About