Central Coast Health officials are reporting an increase in the number of upper respiratory illnesses. More specifically, RSV. RSV is a common respiratory virus. Officials say most people recover from it in about a week, but it can be especially serious for young children. The spike in RSV cases is concerning to some because hospitals don’t usually start seeing it until after Thanksgiving. RSV causes symptoms that are similar to other colds, but if your child is becoming sicker after the third day, it might be time to take them to a doctor.