Airsacculitis, also known as air sacculitis, aerosacculitis, air sac disease, air sac infection, air sac syndrome and simply sac disease, is a common inflammatory condition of air sacs that occurs in birds and is caused by various microbial (mostly bacterial) taxa. Having multiple different causative agents, the condition is widely distributed around the world. The same term is used for bacterial infection and subsequent inflammation of laryngeal air sacs in non-human primates.