Ships don't have boilers anymore? :p
The Navy has no CV/CVA's left in service and the boilers are not suitable for that.
Navy conventional ran on Diesel Fuel Marine aka DFM. Now we did have an incinerator as well for classified material burns but I'm not sure it would be suitable for Medical Hazmat either because you couldn't control leakage.
Before I retired from n=my civilian profession I worked maintenance in a nursing home. One of my jobs was boxing up Red Bag {medical HAZMAT} to be sent off by a contractor for burning. Our cheap-scape boss would only buy thin gloves and a paper face mask. So we improvised with garbage bags and duct tape for a suit LOL. There was some stuff in those boxes you didn't want have contact with like Staph, Syphilis, TB, to name a few.
I'll say this from experience as well getting stuck makes for an uneasy next twelve months of sweating out blood testing.