Ma'anar ƙamus na kalmar "cross infection" tana nufin watsa ko yaɗuwar cututtuka daga wani mutum zuwa wani, musamman a cikin yanayin kiwon lafiya, inda masu kamuwa da cututtuka daban-daban zasu iya kasancewa kusa da juna. Kamuwa da cuta yana faruwa ne lokacin da ƙwayoyin cuta, irin su ƙwayoyin cuta ko ƙwayoyin cuta, ke canzawa tsakanin mutanen da ba su kamu da nau'in ƙwayoyin cuta iri ɗaya ba. Wannan na iya faruwa ta hanyar tuntuɓar ruwan jiki kai tsaye, gurɓataccen saman ko abubuwa, ko ta iska. Kamuwa da cuta yana da matukar damuwa a cikin saitunan kiwon lafiya, kuma ana ɗaukar matakai daban-daban don hanawa da sarrafa yaduwarsa.