throat infection vs strep throat

throat infection and strep throat both are nouns.

Word	Noun	Adjective	Verb	Adverb
throat infection	Yes	No	No	No
strep throat	Yes	No	No	No

As nouns, throat infection and strep throat are synonyms defined as:

throat infection and strep throat: an infection of the oral pharynx and tonsils by streptococcus

Other synonyms of throat infection include septic sore throat, streptococcal sore throat, streptococcus tonsilitis.

throat infection (noun)	strep throat (noun)
an infection of the oral pharynx and tonsils by streptococcus	an infection of the oral pharynx and tonsils by streptococcus