Commercial porcine circovirus type 2 vaccines: efficacy and clinical application.

Porcine circovirus type 2 (PCV2) is the one of the most economically important pathogens of pigs. After postweaning multisystemic wasting syndrome (PMWS) was first identified and reported in western Canada in 1991, it took 13years for the first commercial PCV2 vaccine to be used under special licence in France and Germany in 2004. Along with PMWS, PCV2 is also associated with a number of diseases and syndromes, collectively referred to as porcine circovirus-associated disease (PCVAD). Currently, five commercial vaccines are available on the international market. Commercial PCV2 vaccines were initially developed to control PMWS, but they are now also used against other PCVAD. This review focuses on (1) the types of commercial vaccines; (2) the criteria of vaccine efficacy; (3) the clinical, virological, immunological and pathological efficacy of the vaccines; and (4) the use of PCV2 vaccines against different clinical manifestations of PCVAD.