How serious is the risk of menigitis to children?

Low: There are very few reported cases of meningitis each year in the U.S. However, if you suspect that your child has meningitis, you must take him or her immediately to an emergency room. Symptoms include, but are not limited to, fever, headache, nausea, vomiting, altered mental state, neck stiffness, rash, etc.

Depends: If they are fully vaccinated, the risk is low. The prime cause of bacterial meningitis up to the mid 90's was H.influenza bacteria. Infant vaccines has dropped the rate by >95%, but unvaccinated kids are at risk. The more common cases of meningitis now are viruses which tend to be milder and less damaging.