I don’t usually agree with the UN, but I see nothing objectionable in this.
If a massive storm hits the coast, and no one suffers injury, is it a disaster?
Storms happen, earthquakes happen, floods happen. But they only become disasters when people insist on living where they happen without taking proper precautions.
It can still be a disaster as it causes destruction, but its impact on mankind is then insignificant if nobody is living there.