Justin Timberlake has shared that he is battling Lyme disease.

The American singer and actor made the announcement in an emotional Instagram post, following the end of his two-year Forget Tomorrow World Tour.

In the post, Timberlake explained that he usually keeps his personal life to himself but felt it was time to be open about what he has been going through.

He revealed that he and his wife, Jessica Biel, who share two sons, had kept the diagnosis private for a while. He admitted he was unsure whether to go public but eventually chose to speak up to be more transparent with his fans.

Timberlake described how the illness has affected him, saying that anyone who has dealt with Lyme disease knows how mentally and physically exhausting it can be. He said he was shocked when he was first diagnosed, but it helped explain why he had been feeling so much pain and fatigue while performing.

He recalled moments during his tour when he was overwhelmed by nerve pain or extreme tiredness on stage. Faced with a tough choice to either stop performing or continue pushing through, he decided to keep going. He said the happiness he feels from performing was worth the physical toll.

Lyme disease is a serious infection spread through tick bites. If not treated properly, it can damage the joints, heart, and nervous system.