Unfortunately, there isn't an official website or a specialized institution where you can report Trojans, malware and viruses that you encounter. Usually, your antivirus program will automatically send a report to the developer when a situation like this is encountered (if you use such a tool). If you want to help other users, to be aware of an infestation, you can report this issue to all of the companies that are developing security programs like BitDefender, Avast, Nod32, etc.
