My Son Is In The Service Received Full Panel Of

My son is in the service received full panel of immunizations 2 months ago, was sick right after that. Now is sick again been revering since Wed, been to base ER got augmenten yesterday. Today still visibly revering sweating. Could there be anymore going on than just normal flu? Not normal for someone to fever this long. Wakes up and bed is soaked. Taking advil and tylenol also.