The big apocalipse

Once in the future there were a huge asteroid which landed in Africa. It didnt made such a big damage but it spreaded out a strange thing called : “formula-A” and a less amount of “formula-B”. The A type was a dangereous kind of zombie desease. The B type was rare to affect on humans. The B type give the affected special atributes. These two things spreaded out every where in the Earth. You once wake up noticing nobody is on the street. Btw you may soon have to end the A type desease and you somehow got affected by the B one. Have fun! (Please dont be mad at voice)