Sources:
https://www.bbc.com/news/world-us-canada-51893445
https://edition.cnn.com/videos/politics/2020/03/14/trump-handshakes-coronavirus-press-briefing-vpx.cnn
https://www.telegraph.co.uk/news/2020/03/14/trump-defends-habit-shaking-hands-coronavirus-pandemic/
Why are you so worried about his health?
Even if he is going to be tested positive he is going to get the best treatment not only in the US but probably all over the world. And despite that, he has a whole team on the background that they are working for eliminating the virus.
I mean -- they're worried for his health because he's the President of the United States and is in the age group where this virus is the most lethal. I think his chance of death if he got Corona would be in the realm of 5-8 percent. You're right regarding the standard of care the President would get, but I don't think it really matters -- maybe it would get him another percent because his doctors are probably watching around the clock for this -- but this is still VERY lethal for someone his age regardless of standard of care.
Wouldn't be good for a country that is already freaking out over a global health crisis to have their President die.