Mydoom is a malware family known to be active since at least 2004, with worm capabilities designed to spread to other victims using a mass e-mailing approach. Thousands of malicious emails delivered by MyDoom all over the world each month target a wide range of industries, from high tech, wholesale, and retail to healthcare, education, and manufacturing. China and the U.S. are the primary recipients of the emails, although distribution remains global and targets many other countries. The most costly virus, inflicting an impressive $38.5 billion in damages.
Source: https://www.bleepingcomputer.com/news/security/notorious-mydoom-worm-still-on-autopilot-after-15-years/