The subject matter of the present invention is a bacterium or a mixture of bacteria having an antagonistic activity with respect to strains of S. aureus, P. aeruginosa, Streptococcus pyogenes, Enterococcus faecium, Enterobacter cloacae, Proteus mirabilis, Bacteroides fragilis, Staphylococcus epidermidis, Propionibacterium acnes, Candida albicans and/or Malassezia furfur as well as the use thereof in the treatment and/or prevention of infections or colonizations related to those pathogens. The invention pertains to care products containing one or more non-pathogenic antagonistic strains intended to prevent and/or treat infections or colonizations on skin, wounds, mucous membranes and appendages.