A child in DD's class (aged 5) has been diagnosed with chicken pox. DD has been immunized but came home from school lethargic, and not wanting to eat, fell asleep on the sofa - very unlike her. I've read that these are some of the first symptoms. While I'm not too worried about her getting it as she's fully immunized, DS is nearly 17 months and so hasn't had the varicella vaccine. I'm going to call the GP in the morning to see if he can get it a month early, or if its too late now seeing as he's been in contact with the children from DDs class, and we may as well wait till the 18 month mark. Do you know how long it takes for the vaccine to take affect?