Hydrogen sulfide produced by streptococcus and enterococcus bacteria has been implicated by Dr. Kenny De Meirleir as a contributing factor in ME/CFS. This therapy may prove very helpful for people who have problems with these bacteria. My wife is XMRV positive and has an overgrowth of streptococcus in her gut. The same stool test showed she had low levels of secretory Iga in her stool. Here is a link with some info about secretory Iga: http://www.articlesbase.com/health-articles/autism-treatment-secretory-iga-immune-function-and-the-mucosal-barrier-1567239.html Dr. Kenny De Meirlier also found people infected with XMRV have lower Iga levels. This could mean that XMRV is suppressing the immune system’s ability to control the balance of intestinal flora, leading to the overgrowth of bacteria like streptococcus and enterococcus that poison the body with hydrogen sulfide.