@Denise1119 I think a lot of people would consider it a breach of etiquette to ask an invasive question about someone's serological status, although the current circumstances have upended a lot of social norms already.
More importantly, self-reporting is not a reliable way to assess the chance that you've been exposed to the virus, especially considering that carriers can pass it on to others without having symptoms. For the safety of yourselves and those around you, you're going to have to get used to assuming that everyone you've encountered in the last few weeks or will in the coming months is potentially infectious - even if they're not sick - and act accordingly.