Kissed my 2 month old on the mouth!

My fiancé took our 2 month old son to his aunts and he said she kissed him on the mouth! I’m upset it’s the middle of flu season and also so many people have cold sores. I’m sure he would’ve noticed a cold sore but what about viral shedding. He thinks I’m being ridiculous but I’d get upset about ANYBODY kissing him on the mouth. I told him to always watch people around the baby I’m so upset..