For d’Hérelle, there was no question as to the nature of his discovery: "In a flash I had understood: what caused my clear spots was in fact an invisible microbe … a virus parasitic on bacteria."
Pre d'Herelleho, nebolo pochýb o povahe jeho objavu: "Bleskurýchle som pochopil: čo spôsobilo moje čisté škvrny bol v podstate neviditeľný mikrób ... vírus parazitujúci na baktérii."