Hillary Clinton diagnosed with pneumonia, cancels California trip, Hillary Clinton Health issue, 9/11 memorial, pneumonia, New York City
Hillary Clinton has been diagnosed with pneumonia by her personal doctor after the US Democratic presidential candidate fell ill at a 9/11 memorial.
The episode has renewed focus on her health less than two months before an election.
She was diagnosed on Friday, the doctor said, but her condition was not made public until Sunday afternoon.
Just hours earlier, a video was posted on social media, apparently showing Clinton stumbling and her knees buckling, before being helped by aides into a black van leaving the site of the September 11, 2001, attack in New York City.
She was taken to her daughter Chelsea's home in the city and appeared on her own about two hours later, wearing sunglasses and telling reporters that she was "feeling great".
Clinton cancelled her campaign trip to California on Monday because of her diagnosis of pneumonia.
Al Jazeera's Kimberly Halkett, reporting from Washington DC, said Clinton's health would now become a "major issue" in the lead-up to the election, "elevated from the ranks of conspiracies to a legitimate campaign issue".
She noted that Sunday's event was Clinton's second health-related incident in a week.
Clinton's speech at a campaign rally on Labour Day in Cleveland was interrupted by a coughing spell. During the speech, she quipped: "Every time I think about Trump I get allergic."
She then resumed her speech.
Clinton has been in the news before for serious health issues.
In December 2012, she suffered a concussion and shortly afterward developed a blood clot.
In a letter released by her doctor in July 2015, Clinton was described as being in "excellent health" and "fit to serve" in the White House. It noted that her current medical conditions include hypothyroidism and seasonal pollen allergies.
The diagnosis and illness on Sunday come after some tough days for Clinton, as national polls showed her lead over Trump diminishing. A Reuters/Ipsos poll of likely voters showed an 8-point lead for Clinton had vanished by the last week of August.
On Saturday, Clinton came under fire from Republicans and on social media for saying Friday night that "half" of Trump's supporters belonged in a "basket of deplorables." She later said she regretted using the word "half."
Trump has also been under pressure to release detailed information on his health and medical history.
Instead, in December, Trump's doctor wrote in a short letter that was made public that his blood pressure and laboratory results "were astonishingly excellent" and that he would be "the healthiest individual ever elected to the presidency."