That’s something I have debated before.
Small pox a was bitch and hard on everyone even though we knew to some extent how to deal with it.
What I have always wondered was did settlers ever intentionally withhold aid or medical knowledge for things we definitely knew how to dealt with? such as the common cold, which to an underdeveloped immune system could be as lethal as small pox.
Its a moot point because there is not allot of evidence to support nor deny this theory however I have always questioned the mentality of settlers and their attitude towards the natives.