Hi, My 10 Yr Old Autistic Son Has Had Ticks

Hi, my 10 yr old autistic son has had ticks for the last 3 weeks. They finally did an ASO Titer which was high, and his DNAse B antibody is 777. I assume he has strep then and should get an antibiotic. They are getting back with us on Mon. Should I be concerned, is he contagious, would this have possibly caused the ticks(mostly head shaking)?