As far as I can recall, Nora was never mentioned again after #45, when Marco lied to his Dad about her being s Controller all along. In #35 Marco says they checked to make sure she wasn't a Controller, and it's unlikely she was infested between those 10 books. She was then infested in #45 when the Yeerks were after Marco's Dad. For all we know, she could have been killed by the end of the war, possibly during the explosion at the Yeerk Pool or in the final fight against the Yeerks in #53 and #54.