1 Viruses such as the flu, norovirus, or rotavirus . Rotavirus is the most common cause of acute diarrhea in children. 2  Parasites, which are tiny organisms found in contaminated food or water.  Medicines such as antibiotics, cancer drugs, and antacids that contain magnesium.
A pedophile is someone who has a primary or exclusive sexual attraction to prepubescent children of either sex. Not every adult who is attracted to children acts on their attraction. There are pedophilic offenders and there are situational offenders.
According to this, pederasty is sexual relations between two males, especially when one of them is a minor. Other definitions, like the one that JSBangs found, differ slightly. But otherwise, I think you answered the question yourself: pedophile refers to the attraction, while pederasty refers to the act itself.