Evaluation of a 20 year old MLV vaccine on recent PRRSv isolates

Evaluation of a 20 year old porcine reproductive and respiratory syndrome (PRRS) modified live vaccine (Ingelvac (R) PRRS MLV) against two recent type 2 PRRS virus isolates in South Korea

By:Jeong, J (Jeong, Jiwoon)^[ 1 ] ; Choi, K (Choi, Kyuhyung)^[ 1 ] ; Kang, I (Kang, Ikjae)^[ 1 ] ; Park, C (Park, Changhoon)^[ 1 ] ; Chae, C (Chae, Chanhee)^[ 1 ]

VETERINARY MICROBIOLOGY

Volume: 192

 

Pages: 102-109

DOI: 10.1016/j.vetmic.2016.07.006

Published: AUG 30 2016

View Journal Information

Abstract

Type 2 porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) was first isolated in Korea in 1994. The commercial PRRS modified live vaccine (Ingelvac (R) PRRS MLV, Boehringer Ingelheim Vetmedica Inc., St. Joseph, Missouri, USA) based on type 2 PRRSV, was first licensed for use in 3- to 18-week-old pigs in Korea in 1996. The objective of the present study was to evaluate the efficacy of this 20 year old commercial PRRS modified live vaccine (MLV) against two recent PRRSV isolates. Two genetically distant type 2 PRRSV strains (SNUVR150004 for lineage 1 and SNUVR150324 for lineage 5), isolated in 2015, were used as challenge virus. Regardless of the challenge virus, vaccination of pigs effectively reduced the level of viremia, the lung lesions, and of the PRRSV antigen within the lung lesions. The induction of virus specific interferon-gamma secreting cells by the PRRS vaccine produced a protective immune response, leading to the reduction of PRRSV viremia. There were no significant differences in efficacy against the two recently isolated viruses by the PRRS MLV based on virological results, immunological responses, and pathological outcomes. This study demonstrates that the PRRS MLV used in this study is still effective against recently isolated heterologous type 2 PRRSV strains even after 20 years of use in over 35 million pigs (C) 2016 Elsevier B.V. All rights reserved.

Keywords

Author Keywords:Porcine reproductive and respiratory; syndrome virus; Respiratory disease; PRRSV modified live vaccine; Vaccine efficacy

KeyWords Plus:POLYMERASE-CHAIN-REACTION; REAL-TIME PCR; NORTH-AMERICAN; LELYSTAD VIRUS; PROTECTIVE IMMUNITY; MOLECULAR-BIOLOGY; CHALLENGE; INFECTION; PIGS; US

Author Information

Reprint Address: Chae, C (reprint author) 

Seoul Natl Univ, Coll Vet Med, Dept Vet Pathol, 1 Gwanak Ro, Seoul 151742, South Korea.

Addresses:

[ 1 ] Seoul Natl Univ, Coll Vet Med, Dept Vet Pathol, 1 Gwanak Ro, Seoul 151742, South Korea

E-mail Addresses:swine@snu.ac.kr