The international community may prioritize the issue of nuclear war, but world leaders are overlooking another, greater threat: A genetically engineered virus.

That’s what billionaire Bill Gates said Saturday during the Munich Security Conference, the Washington Post reports. Gates told world leaders that bioterrorism, whether naturally occurring or manufactured by people, has the potential to kill more people than nuclear weapons.

“The next epidemic has a good chance of originating on a computer screen,” Gates said.

He added that it could kill tens of million of people, the Post reports.

Gates also stressed that governments need “to prepare for these epidemics the same way we prepare for war.”