Both have some say in how we respond to this sort of thing. To put talk of the blame or praise on either of them would obviously be silly-- but they certainly dictate some of the response.

The original Trump tweet is fucking stupid-- of course Obama isn't and can't be held responsible for the development of ebola in certain varieties of lettuce-- but it's a little disobedience to compare the ebola crisis with coronavirus. With ebola, it came through for la known sort of food, and it could be countered by simply not eating that specific food. Coronavirus spreads human to human, and someone might be infectious without displaying symptoms for up to two weeks.

Even if we had someone competent in office, containing the coronavirus would be like trying to contain the flu or the common cold, in terms of how the disease spreads. It's a Herculean task.