| − | A zymotic disease is a disease of a contagious nature, presumed to be due to some virus or organism which acts in the system like a ferment.<ref>{{Nuttall|Zymotic Diseases}}</ref> | + | A '''zymotic disease''' is a disease of a contagious nature, presumed to be due to some virus or organism which acts in the system like a ferment.<ref>{{Nuttall|Zymotic Diseases}}</ref> |