Baby sick from daycare

My son started daycare about 3 weeks ago, he’s 7.5 months old. Within the first 3 days of starting, he got sick. He had a really bad sinus infection that lasted about a week, he’s had a very bad snotty nose the last couple of weeks, and now he’s running a 102 degree temp with an ear infection. My poor baby cannot catch a break. Did this happen to anyone else with kids in daycare? I know kids get sick often, but please tell me he’s not going to be miserable like this forever.