Justin Bieber Reveals He's Battling Lyme Disease in Upcoming Documentary Series

Fans have long known about Justin Bieber‘s ongoing struggle with mental health, but according to reports, another illness has been taking a toll as well.

According to TMZ, an upcoming 10-part docu-series on YouTube Originals called Justin Bieber: Seasons reveals that he has been quietly suffering from Lyme disease — an infectious disease spread by ticks.

The outlet reports that sources who have seen the docu-series say Bieber and his family discuss some of the symptoms he was experiencing throughout 2019 before doctors were able to diagnose the disease.

Bieber, 25, reportedly went undiagnosed until late last year, receiving countless treatments in the process that only made his symptoms worse.

Common signs of Lyme disease in its initial stages include fever, headache, fatigue, and a skin rash called erythema migrans, according to the Centers for Disease Control and Prevention.

It can typically be treated after several weeks of antibiotics. However, if left untreated, symptoms can develop into facial palsy, irregular heart beat, nerve pain, and even inflammation of the brain and spinal cord.

Just last year, fellow singer Avril Lavigne came forward with her own battle with the disease, which left her bedridden for two years, explaining that it was the reason behind her four year hiatus. Country music star Shania Twain had to undergo multiple invasive surgeries to treat the damaging effects of dysphonia, which she says was caused by her own battle Lyme disease.

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Throughout 2019, Bieber was often open with his fans about his struggles and treatment for mental health issues, which was the cause of the singer’s own four-year hiatus from his solo music career.

In February, a source told PEOPLE that the singer was going through a rough patch, but that he was “receiving some treatment” to get better.

“Justin seems down and tired. He has been struggling a bit,” the Bieber source said, adding that the 24-year-old pop star’s difficulties didn’t have anything to do with to his then recent marriage to Hailey Baldwin.

“It has nothing to do with Hailey — he is very happy being married to her. It’s just something else that he struggles with mentally,” the source added at the time. “He has good help around him and is receiving some treatment. He seems confident he will feel better soon.”

Then in March, Bieber shared a vulnerable post on Instagram, telling his followers that he had been “struggling a lot.”

“Just wanted to keep you guys updated a little bit hopefully what I’m going through will resonate with you guys. Been struggling a lot. Just feeling super disconnected and weird,” he wrote, including a picture of himself praying next to manager Scooter Braun and Kanye West.

However, he remained optimistic and went on to assure his fans that he had faith he would rebound quickly.

“I always bounce back so I’m not worried just wanted to reach out and ask for your [sic] guys to pray for me. God is faithful and ur prayers really work thanks .. the most human season I’ve ever been in facing my stuff head on,” wrote Bieber at the time.

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Ahead of the new year, the pop star seemingly did bounce back and announced a slate of new projects, including an upcoming album and his documentary series.

On New Year’s Eve, he shared the trailer for Justin Bieber: Seasons, which showed interviews with various people in the singer’s life — including Braun, Baldwin and Bieber himself. The footage began by addressing Bieber’s long hiatus.

“As humans we go through so many ups and downs, so many good seasons and bad seasons, sometimes we want to give up,” Bieber says in the clip.

“He’s taken a very long break and in that time, he’s found his wife, he’s grown a lot, and he’s ready to express himself through music again,” Braun says. “No one’s ever grown up in the history of humanity like Justin Bieber.”

The first episode of Justin Bieber: Seasons airs at 12:00 p.m. EST on YouTube on Jan. 27. The episodes will air on Mondays and Wednesdays.