I think it's better not go to school. It's a kind of ill and the baby may not feel well nei. Actually, it tooks for a week. When my son was 1 years old, he has got this ill, and stayed in St. Paul Hospital for 5 days. The very high fever kept for a 4 days. On the 4th days, the fever gone then the little red dots were on his body. Don't know is it ichy? The doctor said he wont' spread to others. My nephew also got this when he was 1 yrs old. He got the morning fever (not too high) only and the little red dots show on his body in afternoon.....and gone after 2 days.........The reaction not same to the different baby.
It's not a servious ill, don't worry, be happy. cheers/mummyamy