Welcome to the forum. I agree with the brief responses you had on the community forum.
To my knowledge, all blood specimen lancets currently on the market are designed for single use, and I believe all are designed to prevent more than one use. But I have no personal experience with them and cannot say whether that safety feature might be defeated by a specific effort to do so. However, I also cannot imagine why anybody would ever do that. In any case, in the past 20+ years nobody in the world has caught HIV through the specimen collection process, either with lancets, syringes, or other blood-collection methods. I see no reason for any concern about it and suggest you not research it further, which likely would serve primarily to reinforce the anxiety you apparently have about it.
Regards-- HHH, MD