Advance in Porcine Circovirus Type 2 Vaccine

Porcine circovirus type 2(PCV-2) is the causative agent of a collection of disease syndromes in pigs,now known as porcine circovirus diseases(PCVDs) in Europe or porcine circovirus associated diseases(PCVADs) in the United States,which results in tremendous economic losses.The recent commercially available inactivated and subunit vaccines based on PCV-2a genotype provide an excellent tool for decreasing mortality and increasing growth parameters in commercial swine herds.Since 2003,concurrence with the increased severity of clinical disease,the predominant prevalence subtypes has been shifted from PCV-2a to PCV-2b in global swine populations.Although the current commercial vaccines based on PCV-2a have very good efficacy which can also provide cross-protection against PCV-2b,novel experimental vaccines such as modified live-attenuated vaccines based on PCV-2b are being developed and may provide a superior protection and reduce vaccine costs.This review assessed the efficacy of the currently available commercial PCV-2 vaccines in experimental and field conditions,and providea insight into the development of new novel vaccines against PCV-2.