Husband has covid…I don’t

Brianna

So I’m 6 weeks pregnant. We have a 2 year old. My husband received the first dose of the vaccine on Tuesday and started feeling sick Friday. We assumed it was a reaction to the vaccine and thought nothing of it. Sunday he tested positive for covid. It’s now Tuesday and we have been together the whole time. I’ve taken care of him, we’ve shared a bed, food, water. I’m so thankful I’m not sick but am curious why this would be?