Sickness

Hey all, my fiancé had an episode last night where he had a headache, felt dizzy and nauseous. When he got up to go to the bathroom early this morning, he ended up getting lightheaded and falling down. We were at a surprise proposal bbq last night and he hadn’t eaten anything or drank any water since breakfast that morning. We don’t know if it was just cause he ate too much too fast and was drinking or if it’s a virus. Can my 3 month old catch it if it is a virus??