Waste or Wastes

"What treatment methods are used for Ebola or other Category A medical waste?"

The use of the conjunction OR means you would use a singular noun, regardless of any other possibilities, as there is only one category here with an or.

• French bread
• sliced bread

*Do you want to serve French or sliced bread at the dinner?*

Breads would not work here. [Yeah, I know you could, if you really wanted to, come up with a plural if there were different kinds of French bread and sliced bread but here they are categories of bread, so please do not.]

Medical waste of the same category (infectious waste) would not take an s.

[Sorry, no reference as this question should probably be on ELL anyway.]