respiratory infection vs respiratory tract infection

respiratory infection and respiratory tract infection both are nouns.

Word	Noun	Adjective	Verb	Adverb
respiratory infection	Yes	No	No	No
respiratory tract infection	Yes	No	No	No

As nouns, respiratory infection and respiratory tract infection are synonyms defined as:

respiratory infection and respiratory tract infection: any infection of the respiratory tract

respiratory infection (noun)	respiratory tract infection (noun)
any infection of the respiratory tract	any infection of the respiratory tract