They are related genres, Jazz developed from the Blues, They both grew out of the African American experience. and are influenced by western music, and instrumentation.
Blues is more formulaic, and stresses Vocals as well as musician ship, It is often about raw emotion and sexuality. Emotive honesty, and expression are paramount. Songs are built around melodies and improvisation is left for solos. Technic and improvisation are secondary to emotive expression.
Jazz is a more technically demanding genre, Improvisation is very highly accentuated, vocals are often not used, favoring longer improvisational solos. Structured melodies are used as frameworks to Improvisation . Time signatures are more complex, and may vary during the songs.