Outbreaks, or false negatives, are files whose evolution in time has changed from almost no detection to being detected by several anti-malware engines. This happens because when new malware is released, only a few or even no engines will detect the file as being infected by using static analysis. As time passes, more engines will start to detect and label the file as malicious. Anti-malware engines use signature databases to detect malware, and MetaDefender Cloud makes sure to always have the latest signatures for all it's engines, so that outbreak detection happens as soon as possible