scholarly journals Early and Solid Protection Afforded by the Thiverval Vaccine Provides Novel Vaccination Alternatives Against Classical Swine Fever Virus

Vaccines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 464
Author(s):  
Yaneysis Lamothe-Reyes ◽  
José Alejandro Bohórquez ◽  
Miaomiao Wang ◽  
Mònica Alberch ◽  
Marta Pérez-Simó ◽  
...  
Keyword(s):  
Classical Swine Fever Virus ◽  
Virus Transmission ◽  
Humoral Response ◽  
Classical Swine Fever ◽  
Vaccine Virus ◽  
Fever Virus ◽  
Post Vaccination ◽  
Vaccination Programs ◽  
Strain Vaccine ◽  
Clinical Protection

Classical swine fever virus (CSFV) remains a challenge for the porcine industry. Inefficient vaccination programs in some endemic areas may have contributed to the emergence of low and moderate virulence CSFV variants. This work aimed to expand and update the information about the safety and efficacy of the CSFV Thiverval-strain vaccine. Two groups of pigs were vaccinated, and a contact and control groups were also included. Animals were challenged with a highly virulent CSFV strain at 21- or 5-days post vaccination (dpv). The vaccine induced rapid and strong IFN-α response, mainly in the 5-day immunized group, and no vaccine virus transmission was detected. Vaccinated pigs showed humoral response against CSFV E2 and Erns glycoproteins, with neutralising activity, starting at 14 days post vaccination (dpv). Strong clinical protection was afforded in all the vaccinated pigs as early as 5 dpv. The vaccine controlled viral replication after challenge, showing efficient virological protection in the 21-day immunized pigs despite being housed with animals excreting high CSFV titres. These results demonstrate the high efficacy of the Thiverval strain against CSFV replication. Its early protection capacity makes it a useful alternative for emergency vaccination and a consistent tool for CSFV control worldwide.

scholarly journals Seroprevalence against classical swine fever virus in vaccinated pigs in Ho Chi Minh City

2020 ◽  
Vol 19 (03) ◽  
pp. 48-51
Author(s):  
Mai C. Duong
Keyword(s):  
Classical Swine Fever Virus ◽  
Humoral Response ◽  
Classical Swine Fever ◽  
Herd Size ◽  
Elisa Test ◽  
Fever Virus ◽  
Ho Chi Minh City ◽  
Serological Response ◽  
Post Vaccination ◽  
Test Kit

The aim of this study was to survey the serological response to classical swine fever disease in vaccinated pigs in Cu Chi, Ho Chi Minh City. By using the PrioCHECK® CSFV Ab 2.0 ELISA test kit to detect antibodies against CSF in 410 vaccinated pigs and IDEXX CSFV Ag Serum Plus Test to detect the Erns protein of the CSFV in pigs without antibodies against CSFV. Results showed that the overall seroprevalence observed in vaccinated pigs in other Farms varied from 70% - 100% (P < 0.05), but in Farm 5, no pigs produced a positive humoral response against CSFV were found. The highest seroprevalence of antibodies against CSFV was found in Farms with a herd size of ≥ 1000 - < 6000 animals (91.26%) and the lowest was a Farms with less than 1000 animals (51.81%). The highest ratio of positive pigs for antibodies against CSFV belonging to Group of > 40 - ≤ 60 days post-vaccination was 98.36%. The lowest rate was found in Group of 30 - ≤ 40 days postvaccination (51.96%). That grower pigs had the highest proportion of positive pigs for antibodies against CSFV accounting for 81.40%; next, the proportion of positive sows was 73.24%. Significant differences in the seroprevalence observed in vaccinated pigs across herd size, days post-vaccination, type of pigs (P < 0.05). In this study, no pig was found to contain CSFV antigen.

scholarly journals Activation of Dendritic Cells in Tonsils is Associated with CD8 T Cell Responses Following Vaccination with Live Attenuated Classical Swine Fever Virus

2021 ◽  
Vol 22 (16) ◽  
pp. 8795
Author(s):  
Ferran Soldevila ◽  
Jane C. Edwards ◽  
Simon P. Graham ◽  
Helen R. Crooke ◽  
Dirk Werling ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
Classical Swine Fever Virus ◽  
T Cell Responses ◽  
Classical Swine Fever ◽  
Cd8 T Cell ◽  
Fever Virus ◽  
Cell Responses ◽  
Strain Vaccine ◽  
Ifn Γ

Classical swine fever (CSF) is a highly contagious disease caused by the classical swine fever virus (CSFV). The live attenuated C-strain vaccine is highly efficacious, initiating protection within several days of delivery. The vaccine strain is detected in the tonsil early after inoculation, yet little is known of the role that tonsillar immune cells might play in initiating protection. Comparing the C-strain vaccine with the pathogenic CSFV Alfort-187 strain, changes in the myeloid cell compartment of the tonsil were observed. CSFV infection led to the emergence of an additional CD163+CD14+ cell population, which showed the highest levels of Alfort-187 and C-strain infection. There was also an increase in both the frequency and activation status (as shown by increased MHC-II expression) of the tonsillar conventional dendritic cells 1 (cDC1) in pigs inoculated with the C-strain. Notably, the activation of cDC1 cells coincided in time with the induction of a local CSFV-specific IFN-γ+ CD8 T cell response in C-strain vaccinated pigs, but not in pigs that received Alfort-187. Moreover, the frequency of CSFV-specific IFN-γ+ CD8 T cells was inversely correlated to the viral load in the tonsils of individual animals. Accordingly, we hypothesise that the activation of cDC1 is key in initiating local CSFV-specific CD8 T cell responses which curtail early virus replication and dissemination.

scholarly journals The E2 Glycoprotein of Classical Swine Fever Virus Is a Virulence Determinant in Swine

2005 ◽  
Vol 79 (6) ◽  
pp. 3787-3796 ◽  
Author(s):  
G. R. Risatti ◽  
M. V. Borca ◽  
G. F. Kutish ◽  
Z. Lu ◽  
L. G. Holinka ◽  
...  
Keyword(s):  
Classical Swine Fever Virus ◽  
Classical Swine Fever ◽  
Vaccine Virus ◽  
Fever Virus ◽  
Genetic Determinants ◽  
Highly Pathogenic ◽  
Virus Shedding ◽  
E2 Glycoprotein ◽  
Viral Virulence

ABSTRACT To identify genetic determinants of classical swine fever virus (CSFV) virulence and host range, chimeras of the highly pathogenic Brescia strain and the attenuated vaccine strain CS were constructed and evaluated for viral virulence in swine. Upon initial screening, only chimeras 138.8v and 337.14v, the only chimeras containing the E2 glycoprotein of CS, were attenuated in swine despite exhibiting unaltered growth characteristics in primary porcine macrophage cell cultures. Additional viral chimeras were constructed to confirm the role of E2 in virulence. Chimeric virus 319.1v, which contained only the CS E2 glycoprotein in the Brescia background, was markedly attenuated in pigs, exhibiting significantly decreased virus replication in tonsils, a transient viremia, limited generalization of infection, and decreased virus shedding. Chimeras encoding all Brescia structural proteins in a CS genetic background remained attenuated, indicating that additional mutations outside the structural region are important for CS vaccine virus attenuation. These results demonstrate that CS E2 alone is sufficient for attenuating Brescia, indicating a significant role for the CSFV E2 glycoprotein in swine virulence.

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