hi, my dad is 07 years old in good health except for arthritis. we live in ny and it is warm andhumid for the past several days. He called a few hours ago and said his body was shaking all over, He wasnt cold, he wasnt hot, he did not have a headache or any other symptom. He has had diarrhea over the past few weeks for a few days at a time. I told him to put his sweater on, have a cup of tea and relax and take a nap. He now has not shaking but is fearful that something major is going on and is talking about going to the hospital......what is your advice...