Posing a blow to his campaign at a decisive time, US President Joe Biden tested positive for Covid-19 on Thursday. A statement by the White House said the President is experiencing mild symptoms.

The President's physician Dr Kevin O'Connor said that Biden presented this afternoon with upper respiratory symptoms, to include rhinorrhea (runny nose) and non-productive cough, with general malaise.

However, the diagnosis comes at a pivotal time for the President, who was supposed to attend a key campaign event aimed at wooing Latino voters.

Though Biden told reporters that “he feels good” before boarding Air Force One to head to his Delaware residence on Wednesday, this has cast a shadow over his reelection bid, which has been teetering ever since his disastrous debate performance.

Biden's Covid diagnosis will raise concerns about his age, health and stamina, that too amid calls from many Democrats to step aside as the party's presidential nominee.

The President being ill for the second time in three weeks also puts the spotlight on the GOP campaign, which is going stronger ever since Presidential nominee Donald Trump survived the assassination attempt,

While Trump paints a picture of strength, rallying supporters with chants of “Fight! Fight! Fight!,” after taking a bullet hit, Biden's image is that of an aging, stiff-gaited, low-talking person.