On Friday, we learned Herrera underwent treatment for pneumonia and a collapsed lung.
Now in an emotional video posted to Facebook, Herrera is talking to his fans, and thanking them for their prayers.
The 57-year-old singer said doctors found an infection on his knee that required surgery, and that his heart may have been affected by the infection.
"I am very ill," Herrera admitted, as he fought back tears. "I want you to know that I'm going to pull through and I'll be back to work soon."
WATCH: Herrera breaks his silence after surgery
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