A lot of people have recovered or got much better from ME/CFS using Papain. The results have also been confirmed by darkfield microscopy or live blood analysis if you like. Anylysis prior to taking Papain showed red blood cells sticking together and beeing malformed, suggesting an underlying infection. After several months the patients recovered and the blood anylysis now showed perfect red blood cells. I don't believe there's any reason to doubt the effects of Papain and all it's positive effects. It's even suggested to support the immune system in fighting cancer cells.
Info about the many suggested benefits of Papain can be found at this link: