Though probably unbelievably to some, I have passed strings even longer than stannard's. I believe the longer you have it the more invasive it becomes, consequently the strings become longer and thicker and therefore stronger to combat!!!!
Now that my body's immune system is ACTUALLY fighting back, I am releasing very small ones, approx 1 inch and about 1 mm....similar to yours : ) Essentially, this means that your immune system (and now mine) are working...not "up to snuff" but it is working.... We just need to give it more help.