Efficacy of Type 2 PRRSV vaccine against Chinese and Vietnamese HP-PRRSV challenge in pigs
| Autor: | Laura C. Miller, Kelly M. Lager, Baoquing Guo, Jamie Henningson, Crystal L. Loving, Han-Chun Yang, Kay S. Faaberg, Marcus E. Kehrli, Sabrina L. Swenson, Susan L. Brockmeier, Matthew A. Kappes, Sarah N. Schlink |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Swine
viruses animal diseases Porcine Reproductive and Respiratory Syndrome Virulence Viremia Vaccines Attenuated Virus medicine Animals Porcine respiratory and reproductive syndrome virus Lung Attenuated vaccine General Veterinary General Immunology and Microbiology biology Vaccination Public Health Environmental and Occupational Health virus diseases Outbreak Viral Vaccines Viral Load Porcine reproductive and respiratory syndrome virus biology.organism_classification medicine.disease Virology Immunity Humoral Titer Infectious Diseases Immunology Molecular Medicine Bronchoalveolar Lavage Fluid |
| Zdroj: | Vaccine. 32(48) |
| ISSN: | 1873-2518 |
| Popis: | Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant reproductive losses in the sow herd and respiratory disease in growing pigs. The virus belongs to the family Arteriviridae and there are two major genotypes. Type 1 is represented by Lelystad virus, the European prototype virus, and Type 2 is represented by the North American prototype virus, VR-2332. Depending on husbandry, immune status of the herd, and virulence of the isolate, the severity of disease and magnitude of economic loss can be variable. Vaccine use is not always successful indicating a lack of cross-protection between vaccine strains and circulating wild-type viruses. To date, there is no clear method to demonstrate if a vaccine confers protection against a specific isolate except for empirical animal studies. In 2006, a new lineage of Type 2 PRRSV emerged in Chinese swine herds that were suffering dramatic losses resulting in those viruses being described as "Highly Pathogenic PRRSV" (HP-PRRSV). Experimental reproduction of severe disease with HP-PRRSV isolates and virus derived from HP-PRRSV clones demonstrated the causal role of this virus. Recently, partial heterologous protection has been reported for Type 1 and Type 2 attenuated PRRSV vaccines against challenge by different Chinese HP-PRRSV isolates providing some hope for reducing economic loss. This paper reports the efficacy of a commercially available Type 2 attenuated vaccine in young pigs against heterologous challenge with a Chinese and Vietnamese HP-PRRSV isolate. When compared to unvaccinated pigs, vaccination decreased the length of viremia and viral titer, diminished the time of high fever and reduced macroscopic lung scores following homologous and heterologous PRRSV challenge. These results demonstrate the potential use of vaccine as an aid in the control of HP-PRRSV outbreaks. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect