Thanks for your query.
History seems that your child is suffering from exanthematous illnes like measles
its a viral infection, it present as a flue followed by rashes all over body, seen mainly in infants and children.
It needs only supportive treatment, continue zithromax
, along with it give her anti histaminics like syp xyzal
and syp mucosolvin, for fever
give any antipyretic
Give her plenty of water. Avoid cold and junk feeds.