What is the most expensive virus in history?

The most pricey computer system infection in history is the Love Bug infection, which was launched in 2000.  https://geogenes.org/?p=336 As soon as a computer system was contaminated, the infection would erase important files and spread itself to other computers.  https://freecex.com/?p=851 The Love Bug infection was ultimately stopped by a team of anti-virus researchers who developed a vaccine that could secure computers from the infection.