The present invention relates to a method for reducing the percentage of concomitant infections in pigs or a herd of pigs caused by pathogens other than PCV2 comprising the step administering to said pig(s) an effective amount of PCV2 antigen or an immunogenic composition comprising PCV2 antigen. It also refers to a method for improving the resistance of pigs against concomitant infections with pathogens other than PCV2, comprising the step administering to said pig(s) an effective amount of PCV2 antigen or an immunogenic composition comprising PCV2 antigen.