According to several sources including the NY Daily News and NY Post, Carlos Beltran remained in his hotel during the Buffalo Bisons, I mean NY Mets 3-1 loss to Pittsburgh.
The Mets had a doctor visit Beltran, and reported that he does not have a Flu since he does not have a fever.
However, he cannot keep any food in his system, so one must wonder what condition he will be in when the stomach virus passes. When one gets a prolonged virus like this it usually leaves the body exhausted and dehydrated. It would not surprise me that when Beltran returns it will take him a week or so to be playing at full strength.
The Mets may be on their way to more illnesses, as an SNY producer came down with the Flu and was traveling with the team to Pittsburgh. It usually take approximately a week or so for symptoms to show up after exposure, so it will be something to keep an eye on.