According to his spokesperson
Well, at least if a succession plan needs to be put in place we know that Pence should be fit to take up the role. That said, an early test here may not be too indicative of anything but Pence is said to be tested for the virus every day.
In any case, we'll have to see how things go in the coming days/weeks with regards to Trump's health condition and the impact that has on the presidential race.