Well, no, this forum (luxury hotels and travel) is almost certainly not infected. I don't get messages like that and I don't know anyone else who does either. It's far, far more likely that it's your computer which is infected and it is something (most likely adware) on your computer generating that message

Try to access the forum from a completely separate computer, one which has never been in contact with any one which gets that message. If you don't see the message, there, that will be further evidence that it is not the forum.

I am going to move this thread to the technical support forum where you will almost certainly get far more information from the knowledgable posters there.

RichardInSF, moderator, luxury hotels and travel