Council leader Sarah Wood said she did not make the comments, which appeared on a social media account in her name in 2020
Sarah Wood, a woman with long brown hair and a green top, wearing a poppy badge and a blue lanyard.
A Reform UK councillor has been challenged over a comment posted on her social media account claiming Long Covid is a myth "made up by the media".
Wood, who is the leader of Kirklees Council, said the comment was "not made by me and did not reflect my personal views, either then or now".
She was asked about the post, dated 31 December 2020, by Green Party councillor Andrew Cooper at a council meeting on Tuesday.
He said: "Do you agree with this statement?" before reading the post which said: "Long Covid is not a thing. It was made up by the media. Get a grip."
Wood replied: "I think you may have a problem with the premise of your question and I did not make that statement."
In a statement, she later said: "My focus now is on the responsibilities I have been elected to deliver for the people of Kirklees.
"That means fixing the council's finances, improving services for all Kirklees citizens and keeping people safe."
She claimed that various supporters had access to the account during political campaigning.
Challenging Wood in the council chamber, Cooper said: "You made that statement, it's in your social media account, so if you made that statement why do you not agree with it now?
He added: "1.5m people in the UK have Long Covid, it is recognised by the World Health Organisation, the US Centre for Disease and Control and the NHS.
"And yet you say here in a social media post, that it is not a thing and was made up by the media."
Andrew Cooper at a council meeting on Tuesday. He wears a green sports jacket and a checked shirt.
According to the NHS, Long Covid, which is sometimes called Post-Covid syndrome, happens when the symptoms of Covid-19 last longer than 12 weeks.
The NHS says the most common symptoms include fatigue, shortness of breath, joint pain and aching muscles and problems with your memory and concentration, which is also called brain fog.
But patient experiences of the condition vary and many report a wide range of debilitating symptoms.
In a statement, Wood later said: "The posts are from an old social media account which was used during political campaigning six years ago.
"The account was accessed and managed by several members of the campaign rather than being used exclusively by me.
"Some of the posts being circulated were not made by me and did not reflect my personal views, either then or now."
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