For all the ferment over Hillary Clinton’s swoon at Sunday’s 9/11 service in New York and the news released hours later by her doctor that she had been diagnosed with pneumonia last Friday, there is no suggestion that her bid for the White House is any immediate and direct peril.

That said, this race is for the most powerful and arguably most gruelling office in the world and any suggestion of health shortcomings in either of the two main candidates will inevitably be taken seriously. Voters want to be confident both will have the stamina for the job.

And, right or wrong, any uncertainty regarding medical fitness is going to have political reverberations on the campaign trail. Uncharacteristically, perhaps, Donald Trump appeared to be restraining himself before using social media to use Ms Clinton’s current illness to try to undermine her candidacy. For how long he will show her that respect remains to be seen.

And uncertainty, of course, breeds more uncertainty. A variety of questions come to mind.

What if Ms Clinton were to become too ill to carry on?

This is not where we are now, as far as anyone knows. But the Democratic Party does have procedures in place should its nominee for president become unexpectedly incapacitated.

Most importantly, however, those procedures would not be triggered until that nominee, in this case Ms Clinton, decides to withdraw from the race. The Democratic National Committee, DNC, the party’s governing body, cannot itself decree that a nominee has become unfit.

Were she to do that, the DNC would meet in urgent session and take a simple majority vote to select someone to replace her. It is a simple as that.

So does that mean they would simply elevate her running mate to the top spot on the ticket?

No. Senator Tim Kaine would be given no special consideration. Rather, the DNC could cast around for a quite different presidential nominee and leave him where he is.

Is this something that is already being talked about after the events of Sunday?

Yes and no. One journalist, David Shuster, once an anchor on cable news, has reported being told by an unidentified source that an emergency meeting of the DNC will be called just to talk about how it would handle things were Ms Clinton to withdraw.

So, who would they consider as a replacement? Someone younger and fitter?

You would think someone a little less aged than either Ms Clinton or Mr Trump, who is 70, might be smart. But so far only two names are in the ether. They are Bernie Sanders, the rumpled Senator from Vermont who gave Ms Clinton a run for her money during the primaries, and Vice President Joe Biden, who thought about running for the top job but in the end demurred. Those gentlemen are 75 and 73 respectively.

But are we getting ahead of ourselves here?

Of course, we are. That said, we are still missing critical information about Ms Clinton’s health status, including what kind of pneumonia she has – bacterial or viral – and how serious it may or may not be. Additionally, this affair is putting a fresh focus on the other health issues she suffers from.

Such as?

Her record is not as trouble-free as some might imagine. Almost forgotten until now was her history of blood clots and deep-vein thrombosis, going back to an event in 1998 when doctors found a clot behind her knee. She was out and about then too, campaigning for Senator Charles Schumer of New York. She later said it was, “the most significant health scare I ever had”.

A second blood clot was found in her legs in 2009. In 2012, when she was still Secretary of State, she took a fall. That led to a concussion and a blood clot in the skull, a possibly serious condition though it resolved itself with blood thinners, which she still takes today. She spent several days in New York-Presbyterian/Columbia University hospital in New York and Bill Clinton commented that it took Ms Clinton about six months fully to recover from that episode.

We didn’t know about all of this already?

We did, but her physician released a letter at the start of her campaign last year attesting to her general good health. Though she did reveal then the daily dose of the blood-thinner, which is coumadin. But generally, Ms Clinton has kept any details of her medical shape close to her vest. She doesn’t like to share anything she considers private with voters, a propensity that in the past has got her into trouble, for instance recently with questions about her use of a private email server while Secretary of State.

What if she falls seriously ill, or worse, after the 8 November election?