
Awtum B. answered 07/09/19
PhD in Immunology and Infectious Disease
If you define infectious as a disease caused by a microscopic organism, and you define contagious as any disease which can be transmitted from person to person, then any disease which is vector-borne (like lyme disease which must be transmitted by ticks, or malaria which must be transmitted by a mosquito) would be considered infectious but not contagious.