The Italy midfielder has been linked with a Serie A return this week.
But Howe, after laughing, said today: "I've got no plans on losing Sandro. I laugh because that just seems out of the blue for me.
"Sandro is a vital part of what we're doing, our investment in him is long term. I've been really pleased with him personally - we've built up a strong relationship.
"He's improving in all aspects of the play, naturally through the games that he's playing. The ban was difficult because he's only training and he's not learning from the game.
"The games are the biggest teacher I think, so I think now he's in a position where he's getting both. I think we're seeing an improvement in all aspects of his game."
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