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In ants, individuals that lost an extremity are cared for by their nestmates. In case of infection, ants often use the metapleural gland, but some genera lost this gland in their evolutionary history. Here we compare two different behaviours to combat an infected wound, one with the metapleural gland and one without. Megaponera analis treats infected wounds with antimicrobial compounds secreted from the metapleural gland, thereby reducing mortality of infected ants by 90%. Further analyses of the metapleural gland secretions of M. analis revealed over 121 chemical compounds and 41 proteins, half of which have an antimicrobial effect. Ants from the genus Camponotus do not have this gland at their disposal. Remarkably, we observed that workers amputated the infected leg by biting it off at its base. This behaviour halted the infection and guaranteed the survival of the injured ant. The large phylogenetic distance between Megaponera and Camponotus and their strikingly different natural history (Megaponera a group-hunting predator, Camponotus a solitary foraging generalist) suggest that wound care behaviour could be much more widespread in social insects. Overall, we reveal a multifaceted care system, which can differentiate between sterile and infected wounds and treats them either with antimicrobial compounds or amputations.