I forgot to mention a couple of other things. Aside from sorting out the Strep. connection right now for your daughter, it's also quite common for girls to have an increase in tics pre-puberty or around onset of puberty and that's certainly something that happened in my daughter's case (I have 2 children, grown now, who have been diagnosed with TS when younger).

Regarding tests for GABHS, it's also my impression that one single positive test is not enough to show a relationship between the tics and the strep.. Meaning that a large proportion of the population will at some time have a Strep test and it will be positive. It's such a common illness. The really important thing is that if there has been a positive culture already and there appears to be a relationship between the strep infections and the tics, then follow-up or longitudinal measurements of antistreptococcal or antinuclear antibody titers should be done over a period of time.

There is more here regarding PANDAS.
http://www.tourettesyndrome.net/pandas_overview.htm
This is certainly something I did with my son who is the one who had the strep connection. If a child has a Strep throat or other Strep related condition e.g. impetigo, scarlet fever etc., then the school should be notified as they're contagious conditions. In the real world that unfortunately doesn't always happen, but I had a good rapport with the school nurse who would inform me when there were reported cases of Strep related illnesses in my son's classroom.

One last thing about Strep. throats. If one person in the family ever gets a Strep. throat then others are at risk. Also, throw out the child's toothbrush. It's simple and cheap to replace and in my opinion worth it.