Ive heard that rumor too but never proved true for me. There is a difference between a steril abcess and a straight up infection tho. I suspect Ive had sterile abcesses in the past but never any harm or fever, and that was due to just huge volumes of oil I was shooting. Only way I could shoot test susp was to mix with a .25cc of oil, put in 1 cc of susp and then another .25cc of oil. Otherwise I just couldnt get it through the needle. The oil acted as a lubricant.