morning long. and one thing is clear -- vladimir putin is not at all clear with the language coming from the white house and not used to it. at least not over the last few years. so this is interesting to see. thank you for being with us. a new study looks at the chance of reinfection from coronavirus. if you had it once, can you still get it again? dr. sanjay gupta, next. ♪ comfort in the extreme. the lincoln family of luxury suvs.