Porcine circovirus type 2 in China: an update on and insights to its prevalence and control

Abstract

Currently, porcine circovirus type 2 (PCV2) is considered the major pathogen of porcine circovirus associated-diseases (PCVAD) that causes large economic losses for the swine industry in the world annually, including China. Since the first report of PCV2 in 1998, it has been drawing tremendous attention for the government, farming enterprises, farmers, and veterinary practitioners. Chinese researchers have conducted a number of molecular epidemiological work on PCV2 by molecular approaches in the past several years, which has resulted in the identification of novel PCV2 genotypes and PCV2-like agents as well as the description of new prevalence patterns. Since late 2009, commercial PCV2 vaccines, including the subunit vaccines and inactivated vaccines, have already been used in Chinese swine farms. The aim of this review is to update the insights into the prevalence and control of PCV2 in China, which would contribute to understanding the epidemiology, control measures and design of novel vaccines for PCV2.

Application of a pathogen microarray for the analysis of viruses and bacteria in clinical diagnostic samples from pigs

“…6 PCV-2 and TTSuV have been previously identified together in association with PMWS. 34 Interestingly, TTSuV was found in most serum samples, including all 6 PCVAD pigs, and was found in the tonsils of 3 pigs removed at 32 dpi because of morbidity associated with PCVAD.…”

Astragalus polysaccharides inhibits PCV2 replication by inhibiting oxidative stress and blocking NF-κB pathway

“…Commercial PCV2 vaccines have already been used in Chinese swine farms since late 2009. However, PCVAD still has high morbility and mortality in some pig farms [27]. Recently, a great deal of interest has been developed to isolate and investigate novel bioactive components with health benefit effects from natural resources.…”

Identification of natural recombinants derived from PCV2a and PCV2b

“…Guo et al (2011) reported that recombinant viruses obtained higher replication with antigenic drift. Another study showed that PCV2 DNA is present in human feces, human vaccines, beef, rodents, and even commercial pig vaccines (Zhai et al, 2014). An increasing number of studies report PCV2 mixed infections, with a high mutation rate in ORF2 and multiple potential epitopes in the Cap protein.…”