Big Hit tweeted a while ago and Allkpop released an article explaining it.
"It turns out, BTS's Jungkook didn't have the flu after all! Big Hit Entertainment has just uploaded an update post regarding Jungkook, who was previously diagnosed with a severe flu. The label wrote, 'While on the 11th, Jungkook was diagnosed with the flu during his 1st examination at an ENT, at a 2nd examination that night through a college-affiliated hospital, we were informed that the flu was a false diagnosis. His high fever was due to the beginning stages of acute tonsillitis, and after receiving appropriate treatment and taking rest, Jungkook has regained his normal health condition. As a result, we notify that Jungkook will participate in all BTS activities related to the special album including music shows and fan sign events as of the 12th. Thanks to all the fans who sent encouragements for Jungkook's recovery.'
Great to hear that he's better~ Stay healthy, Bangtan! ♡ ARMY -- ARTICLE
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