No matter the illness, keep your child home if she has a fever. It may seem harmless enough, but assume any fever is a symptom of a contagious condition. Viruses that cause fevers are contagious as long as the fever is above a 100.4 degrees F. reading rectally. For these, ask your pediatrician if acetaminophen or ibuprofen are safe for your child, and encourage your little one to drink lots of cool fluids. Many parents take their sick child to daycare or birthday parties, but this isn't wise because other kids can get sick. The next time your child has a fever, regardless of the cause, keep her home until it dissipates.