Nosema spores live up to 2 years.
I'd disinfect with clorox solution if it were me, and any sealed honey I'd use as bee feed. I'd scrape down the wax on frames of open nectar, since it's pierco.
I had nosema die outs this winter, and am scraping all the wax off my plastic foundation and removing all wax from frames that were wired foundation. All sealed honey I'm feeding back as spring boost, and all open nectar I'm trashing.
I am starting this year, all wax for broodnest will be new wax each year, making the bees draw it out fresh each year. The old wax (the broodnest wax from the previous year) will be moved up for extracted honey and melted wax. The frames will then be stored for use as foundationless frames in the broodnest the next year.
Living in 95901 ZipCode near Marysville, CA