The saliva of the reduviid species Rhynocoris marginatus (Fab.) and Catamirus brevipennis (Servile) have anti-bacterial activity towards the human pathogens Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Salmonella typhimurium) and one Gram-positive (Streptococcus pyogenes).