Unfortunately, much like the Flu, there will be multiple strains of Covid in short order.
Just because your body is “resistant” to one doesn’t make you immune to others.
So far the reports I’ve seen are that covid-19 is not mutating at a high rate, thus acquired immunity should be durable. China will be the tell, since they’re not on the downside of the initial infection.
It looks like the virus does not mutate like the influenza — so any vaccine / immunity can be longer lasting than usual. See below:
https://www.foxnews.com/media/scientists-offer-hopeful-news-coronavirus-vaccine-mutation-rate