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

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.

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

Vaccines ◽

10.3390/vaccines9050464 ◽

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.

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Porvac® Subunit Vaccine E2-CD154 Induces Remarkable Rapid Protection against Classical Swine Fever Virus

Vaccines ◽

10.3390/vaccines9020167 ◽

2021 ◽

Vol 9 (2) ◽

pp. 167

Author(s):

Yusmel Sordo-Puga ◽

Marisela Suárez-Pedroso ◽

Paula Naranjo-Valdéz ◽

Danny Pérez-Pérez ◽

Elaine Santana-Rodríguez ◽

...

Keyword(s):

Single Dose ◽

Classical Swine Fever Virus ◽

Subunit Vaccine ◽

Classical Swine Fever ◽

Negative Control ◽

Fever Virus ◽

Protein Vaccine ◽

Post Vaccination ◽

Unvaccinated Control ◽

A Subunit

Live attenuated C-strain classical swine fever vaccines provide early onset protection. These vaccines confer effective protection against the disease at 5–7 days post-vaccination. It was previously reported that intramuscular administration of the Porvac® vaccine protects against highly virulent classical swine fever virus (CSFV) “Margarita” strain as early as seven days post-vaccination. In order to identify how rapidly protection against CSFV is conferred after a single dose of the Porvac® subunit vaccine E2-CD154, 15 swine, vaccinated with a single dose of Porvac®, were challenged intranasally at five, three, and one day post-vaccination with 2 × 103 LD50 of the highly pathogenic Cuban “Margarita” strain of the classical swine fever virus. Another five animals were the negative control of the experiment. The results provided clinical and virological data confirming protection at five days post-vaccination. Classical swine fever (CSF)-specific IFNγ T cell responses were detected in vaccinated animals but not detected in unvaccinated control animals. These results provided the first data that a subunit protein vaccine demonstrates clinical and viral protection at five days post-vaccination, as modified live vaccines.

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EVALUATION OF THE PRESENCE OF COLOSTRAL ANTIBODIES IN PIGLETS OF DIFFERENT AGE ORIGINATING FROM SOWS VACCINATED WITH CHINA CLASSICAL SWINE FEVER VIRUS

Archives of Veterinary Medicine ◽

10.46784/e-avm.v2i1.208 ◽

2009 ◽

Vol 2 (1) ◽

pp. 21-27

Author(s):

Jasna Prodanov Radulović ◽

Radoslav Došen ◽

Dušan Orlić ◽

Marko Maljković ◽

Miroslav Valčić ◽

...

Keyword(s):

Classical Swine Fever Virus ◽

Classical Swine Fever ◽

Life Time ◽

Elisa Test ◽

Fever Virus ◽

Maternal Antibodies ◽

Future Research ◽

Precise Control ◽

Immunoenzyme Method ◽

Modified Live Vaccine

Since the placenta is multilayered, there is no transfer of maternal antibodies into the pig fetal circulation, so passive immunity is completely acquired by post-farrowing colostral intake. When speaking about investigation of maternal immunity, the problem of lasting colostral protection of piglets deriving from sows that were repeatedly vaccinated with modified live vaccine (China strain - C strain) is stressed. The objective of this investigation was to detect the presence of maternal antibodies against classical swine fever virus (CSFV) in piglets of different age deriving from sows that were repeatedly vaccinated with China strain CSFV. The examination was carried out on 35 piglets of different age deriving from sows that were repeatedly vaccinated with C-virus strain of CSF by applying immunoenzyme method (ELISA test). On the bases of obtained serological results, it may be concluded that in farm conditions there was a certain number of piglets that did not suck sufficient quantity of colostrum in early post-farrowing period and the problem may be analyzed from the aspect of half-life time of maternal antibodies against CSF. Certainly, future research should include laboratory methods that can provide more precise control of changed values of antibody titre against CSFV, both in sows and in piglets of different age with the aim to view the dynamics of persistence specific antibodies against CSFV in vaccinated pig population.

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ARFGAP1 binds to classical swine fever virus NS5A protein and enhances CSFV replication in PK-15 cells

Veterinary Microbiology ◽

10.1016/j.vetmic.2021.109034 ◽

2021 ◽

Vol 255 ◽

pp. 109034

Author(s):

Liang Zhang ◽

Mingxing Jin ◽

Mengzhao Song ◽

Shanchuan Liu ◽

Tao Wang ◽

...

Keyword(s):

Classical Swine Fever Virus ◽

Classical Swine Fever ◽

Fever Virus ◽

Ns5a Protein

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Genome Variability of Classical Swine Fever Virus during the 2018–2020 Epidemic in Japan

Veterinary Microbiology ◽

10.1016/j.vetmic.2021.109128 ◽

2021 ◽

pp. 109128

Author(s):

Tatsuya Nishi ◽

Katsuhiko Fukai ◽

Tomoko Kato ◽

Kotaro Sawai ◽

Takehisa Yamamoto

Keyword(s):

Classical Swine Fever Virus ◽

Classical Swine Fever ◽

Fever Virus ◽

Genome Variability

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A Novel E2 Glycoprotein Subunit Marker Vaccine Produced in Plant Is Able to Prevent Classical Swine Fever Virus Vertical Transmission after Double Vaccination

Vaccines ◽

10.3390/vaccines9050418 ◽

2021 ◽

Vol 9 (5) ◽

pp. 418

Author(s):

Youngmin Park ◽

Yeonsu Oh ◽

Miaomiao Wang ◽

Llilianne Ganges ◽

José Alejandro Bohórquez ◽

...

Keyword(s):

Vertical Transmission ◽

Classical Swine Fever Virus ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

Vaccine Dose ◽

Classical Swine Fever ◽

Fever Virus ◽

Tissue Samples ◽

Marker Vaccine ◽

E2 Glycoprotein

The efficacy of a novel subunit vaccine candidate, based in the CSFV E2 glycoprotein produced in plants to prevent classical swine fever virus (CSFV) vertical transmission, was evaluated. A Nicotiana benthamiana tissue culture system was used to obtain a stable production of the E2-glycoprotein fused to the porcine Fc region of IgG. Ten pregnant sows were divided into three groups: Groups 1 and 2 (four sows each) were vaccinated with either 100 μg/dose or 300 μg/dose of the subunit vaccine at 64 days of pregnancy. Group 3 (two sows) was injected with PBS. Groups 1 and 2 were boosted with the same vaccine dose. At 10 days post second vaccination, the sows in Groups 2 and 3 were challenged with a highly virulent CSFV strain. The vaccinated sows remained clinically healthy and seroconverted rapidly, showing efficient neutralizing antibodies. The fetuses from vaccinated sows did not show gross lesions, and all analyzed tissue samples tested negative for CSFV replication. However, fetuses of non-vaccinated sows had high CSFV replication in tested tissue samples. The results suggested that in vaccinated sows, the plant produced E2 marker vaccine induced the protective immunogenicity at challenge, leading to protection from vertical transmission to fetuses.

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