Sadly, the research on that is still not conclusive, so I can't give you an answer for that. Some worry about reinfection being possible, some claim that cases of reinfection are only people who have been mistakenly declared recovered. Some say that a vaccine may provide greater immunity than an actual infection. Some say we might not even get a vaccine.
It's still pretty much in the air right now, which is why it's important to look for both potential vaccines and medication. If we can't vaccinate, we must try to treat.