What is the genus species name for streptococcus? what body system does it affect the most/ is there a treatment or cure?

Very treatable: Most streptococcus species are sensitive to penicillin and related antibiotics. It is common in skin infections, urinary tract and certain pneumonia in the lungs. It is especially implicated in a condition called "strep throat" in children and in "scarlet fever." if not treated this may result in rheumatic fever leading to heart valve disease, kidney disease etc.

Numerous: The organism causing strep throat is streptococcus pyogenes. There are many other species of streptococci that can produce a wide variety of diseases in humans, too many to enumerate here.