typhus vs rickettsial disease

typhus and rickettsial disease both are nouns.

Word	Noun	Adjective	Verb	Adverb
typhus	Yes	No	No	No
rickettsial disease	Yes	No	No	No

As nouns, rickettsial disease is a hypernym of typhus; that is, rickettsial disease is a word with a broader meaning than typhus:

typhus: rickettsial disease transmitted by body lice and characterized by skin rash and high fever
rickettsial disease: infectious disease caused by ticks or mites or body lice infected with rickettsial bacteria

Other hypernyms of typhus include rickettsiosis.

typhus (noun)	rickettsial disease (noun)
rickettsial disease transmitted by body lice and characterized by skin rash and high fever	infectious disease caused by ticks or mites or body lice infected with rickettsial bacteria