Blog
About

7
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Evaluación en campo de un candidato vacunal por subunidad proteica E2 contra peste porcina clásica Translated title: Field evaluation of protein subunit2 vaccine candidate against classical swine fever

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Entre las enfermedades con alto potencial de diseminación transfronteriza y elevado impacto económico para los porcicultores de todos los sectores se encuentra la peste porcina clásica (PPC), también conocida como cólera porcino. No obstante los esfuerzos para su control, tras su reemergencia en 1993, el comportamiento endémico que se constata motivó el desarrollo de una vacuna por subunidad proteica E2 (VE2) del virus de la PPC (VPPC) para apoyar la erradicación de la enfermedad, al facilitar la diferenciación de cerdos infectados de vacunados. Luego de los resultados preclínicos satisfactorios, se evaluó la eficacia de la VE2 en un rebaño de ciclo completo con más de 5 000 cerdos, sujeto a vacunación sistemática con una vacuna viva atenuada lapinizada (Cepa China), pero con antecedentes de brotes esporádicos de enfermedad. Se realizó monitoreo de la respuesta serológica mediante ensayo de neutralización de la peroxidasa (NPLA), en diferentes etapas del ciclo productivo de tres grupos de animales (seroperfiles), desde cría hasta ceba, a intervalos de 12 semanas entre grupos, durante un año. Se constataron elevados porcentajes de animales con títulos considerados protectivos (³ 1:100), los que avalan una respuesta humoral satisfactoria a nivel poblacional. A su vez, las cebas positivas a Inmunoperoxidasa Directa (IPD) en tonsilas en el matadero disminuyeron durante el periodo. La evolución favorable del estado de salud del rebaño, tras la vacunación con la VE2, se revirtió en niveles productivos superiores. Los resultados preliminares obtenidos avalan favorablemente el desempeño de la vacuna E2 en condiciones de campo, pese al reto de la circulación viral que propicia el endemismo de la enfermedad y la presencia de otros patógenos

          Translated abstract

          The Classical Swine Fever (CSF), also recognized as hog cholera, is among the diseases with high transboundary spreading potential and economic impact for swine breeders of all the sectors. Despite the efforts for its control since its re-emergence in 1993, the disease endemic behavior observed motivated development of a protein subunit E2 vaccine candidate (VE2) to support the disease eradication, in view of the easy differentiation of infected from vaccinated pigs. After successful preclinical assays, the VE2 efficacy was evaluated in a herd of complete productive cycle with more than 5 000 pigs under routine vaccination with a live attenuated vaccine (Chinese Strain), but with reports of sporadic outbreaks of the disease. Monitoring of the serological response was carried out by the neutralization peroxidase-linked assay (NPLA) in different phases of the productive cycle of three animal groups (serum profiles), from litter to fattener, at 12 weeks interval for one year. High percentages of positive animals with titters considered as protective (³ 1:100) were observed, supporting a satisfactory humoral response at population level. Likewise, the fatteners positive to the Direct Immunoperoxidase (DIP) in tonsils decreased at the slaughterhouse during the study period. The favorable evolution of herd health status after VE2 vaccination led to higher productive levels. The preliminary results obtained favorably support the VE2 performance in field conditions, despite the challenge of the virus circulation favored by the disease endemic condition and other pathogen presence

          Related collections

          Most cited references 52

          • Record: found
          • Abstract: found
          • Article: not found

          Introduction to classical swine fever: virus, disease and control policy.

          Classical swine fever virus is a spherical enveloped particle of about 40-60 nm in diameter with a single stranded RNA genome of about 12,300 bases with positive polarity, classified as a pestivirus within the family Flaviviridae. Natural hosts are domestic and wild pigs. The virus causes one of the most severe diseases in pigs world wide with grave economic consequences. The clinical picture of classical swine fever is variable, depending on the age of the affected animals and viral virulence. The virus is well characterised and reliable laboratory diagnostic procedures are available. In many parts of the world live attenuated vaccines are being used as a safe and efficient prophylactic tool. However, in EU Member States and several other countries vaccination is prohibited and CSF is controlled by a strict stamping out policy. In order to overcome the disadvantages of conventional vaccination inactivated marker vaccines have been developed that enable the distinction between vaccinated and infected animals. Whether these vaccines will be accepted as an additional tool in the framework of the stamping out policy is not yet decided.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Vaccinology of classical swine fever: from lab to field.

             J van Asperen (2003)
            There are two types of classical swine fever vaccines available: the classical live and the recently developed E2 subunit vaccines. The live Chinese strain vaccine is the most widely used. After a single vaccination, it confers solid immunity within a few days that appears to persist lifelong. The E2 subunit vaccine induces immunity from approximately 10-14 days after a single vaccination. The immunity may persist for more than a year, but is then not complete. The Chinese strain vaccine may establish a strong herd immunity 1-2 weeks earlier than the E2 vaccine. The ability of the Chinese vaccine strain to prevent congenital infection has not been reported, but the E2 subunit vaccine does not induce complete protection against congenital infection. Immunological mechanisms that underlie the protective immunity are still to be elucidated. Both types of vaccine are considered to be safe. A great advantage of the E2 subunit vaccine is that it allows differentiation of infected pigs from vaccinated pigs and is referred to as a DIVA vaccine. However, the companion diagnostic E(rns) ELISA to actually make that differentiation should be improved. Many approaches to develop novel vaccines have been described, but none of these is likely to result in a new DIVA vaccine reaching the market in the next 5-10 years. Countries where classical swine fever is endemic can best control the infection by systematic vaccination campaigns, accompanied by the normal diagnostic procedures and control measures. Oral vaccination of wild boar may contribute to lowering the incidence of classical swine fever, and consequently diminishing the threat of virus introduction into domestic pigs. Free countries should not vaccinate and should be highly alert to rapidly diagnose any new outbreak. Once a new introduction of classical swine fever virus in dense pig areas has been confirmed, an emergency vaccination programme should be immediately instituted, for maximum benefit. The question is whether the time is ripe to seriously consider global eradication of classical swine fever virus.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Factors critical for successful vaccination against classical swine fever in endemic areas.

              Classical swine fever (CSF) or hog cholera, caused by the classical swine fever virus (CSFV), is one of the most important viral diseases that cause serious economic loss to the swine industry worldwide. During the past 5 years, several techniques for measuring porcine cell-mediated immunity (CMI) were applied, in conjunction with other conventional techniques, to study factors that influence the induction of CSFV-specific immunity. Information, obtained from a series of experiments, demonstrated cell-mediated immune responses in providing protective immunity against CSF infection. Although it has been confirmed that commercially available modified live CSF vaccines are able to induce complete protection in vaccinated pigs, several factors including maternal immunity, the age of primary vaccination, vaccination protocol and complications caused by other pathogens, can greatly affect the effectiveness of CSF vaccines in the field.
                Bookmark

                Author and article information

                Contributors
                Role: ND
                Role: ND
                Role: ND
                Role: ND
                Role: ND
                Role: ND
                Role: ND
                Role: ND
                Journal
                rsa
                Revista de Salud Animal
                Rev Salud Anim.
                Centro Nacional de Sanidad Agropecuaria (La Habana )
                2224-4700
                December 2015
                : 37
                : 3
                : 143-151
                Affiliations
                [1 ] Centro Nacional de Sanidad Agropecuaria (CENSA) Cuba
                [2 ] Centro de Ingeniería Genética y Biotecnología (CIGB) Cuba
                S0253-570X2015000300002

                http://creativecommons.org/licenses/by/4.0/

                Product
                Product Information: SciELO Cuba
                Categories
                ACOUSTICS

                Comments

                Comment on this article