The ones with strep who never show signs are carriers. I was a carrier of the virus for many years growing up. I never displayed any symptoms, but always tested positive. Don't despair Lauren, strep is going around. My 3 year old has 17 children in his class, 6 have gotten the strep virus in the past month, mine included. Now my oldest has been playing with the kid across the street who has had strep for months, and he sleeps with my youngest, who has tested positive for strep. So far, my oldest has always tested negative. Some people are just more prone to the strep virus than others.
MM gave very good advice on changing the tooth brush, and I have always been told after 24 hours on an antibiotic to wash the sheets in hot water. Up until last year, I always washed sheets in cold water or warm at best, but my oldest is allergic to dust mites and hot water is the only way to kill the mites. While I was talking to the allergist, she mentioned that most germs will still thrive in sheets washed in cold or warm water, and that I have a better chance of killing more germs with hot water. Whether or not that is true or not, I don't know.