The news comes few days after the striker pulled out of Ghana's 2018 World Cup qualifying encounter with Congo on Tuesday over a stomach problem.
Having featured in the costly home draw with the Red Devils on Friday, there had been suspicion that the striker may have withdrawn due to the accompanying public outrage of his disappointing showing until social media pictures confirmed his admission at a local hospital.
“Jordan is fit and well after he missed a game through illness and some worrying pictures emerged of him in a hospital bed,” Swansea boss Paul Clement told pressmen on Thursday.
“He trained on his own yesterday and was in full training today.
“I believe he was in hospital but it was just a precautionary measure and he is now okay.”
Back to club duty, Ayew is expected to lead the Swans attack on Sunday, alongside Tammy Abraham and latest signing Wilfried Bony, having hit top form prior to the international break.