Because of the infection, Bieber told fans he'll have to cancel a series of shows until he can get movement back on the right side of his face.
"As you can probably see from my face, I have this syndrome called Ramsay Hunt syndrome," he says in the video. "As you can see, this eye is not blinking. I can't smile on this side of my face. This nostril will not move, so there's full paralysis on this side of my face."
Bieber tries to smile, blink, and move his face during his video to fans, but one side of his face remains still as he continues to speak.
"So for those who are frustrated by my cancellations of the next shows, I'm just physically, obviously not able of doing them," he says. "This is pretty serious as you can see."
Bieber says he's been doing facial exercises to try to regain movement, but it will take time to recover.
"I wish this wasn't the case but obviously my body is telling me I gotta slow down," he says. "I hope you guys understand, and I'm using this time to just rest and relax and get back to 100% so I can do what I was born to do. But in the meantime, this ain't it."
The virus that causes Ramsay Hunt syndrome is called varicella-zoster virus, which is in the herpes virus family; it’s the same pathogen behind chickenpox in children and shingles in adults, according to the National Organization for Rare Disorders.
It’s unclear how Bieber contracted the virus, but it’s possible he may have contracted the germ several years ago during a bout with chickenpox. The virus, which is not contagious, can lie dormant in your body for years before reactivating and spreading to a facial nerve near your ear, developing into either shingles or in some cases, Ramsay Hunt syndrome, for reasons that are unknown.
As in Bieber's case, people with RHS typically experience some degree of facial paralysis or weakness on one side of the face and a rash on the outer part of the ear, though both symptoms aren’t guaranteed.
Other symptoms that may accompany RHS are ringing in the ear, temporary hearing loss, nausea, vomiting, dry eyes, ear pain, and loss of taste.
The syndrome emerges in about 5 out of every 100,000 people in the US each year, the National Organization for Rare Disorders says, although its prevalence may be underestimated because cases are often misdiagnosed.
Anyone who has had chickenpox can develop RHS at some point, most likely during adulthood. Most cases occur among older adults; children are rarely affected.
Antiviral medications like acyclovir or famciclovir — both used to treat herpes virus infections — together with corticosteroids can treat RHS. However, some symptoms could become permanent, like facial paralysis and hearing loss. Eye drops can help protect the cornea from drying out if people cannot blink, as is the case with Bieber. In his message, he said it wasn't clear how long it may take before he gets better.
"It's going to be OK," Bieber says. "I hope, and I trust God and I trust that this is all going to, it's all for a reason."