What is the most costly bug in history?

The most costly computer system infection in history is the Love Bug virus, which was released in 2000. Once a computer was contaminated, the infection would delete crucial files and spread itself to other computer systems.  https://tastykoreachannel.com/?p=382 The Love Bug infection was eventually stopped by a team of anti-virus scientists who created a vaccine that might safeguard computer systems from the infection. https://scarabnet.org/?p=1184