Absolutely! I've had one dck who has been sick literally with one virus after another since Oct. Mom continues to send her daily and then the others all end up with something. She has been on antibiotics 3 times since October but it doesn't seem to be helping her at all. She coughs non-stop and I mean non-stop...whether she's playing, eating, sleeping or sitting for quiet time. She took 2 weeks off over Christmas and all the other dck's got better, she came back and now they are all sick with something again! (she apparently was sick the entire 2 weeks she was off too). Luckily my own children haven't had much!