Who brought up religion? Ya, the flu has killed millions, and we are preventing that from ahppening again with flu shots. Did the flu cause billions of dollars of damage? Leveling entire countries? Anyway you look at it, it's a sad event that the whole world has dwelled on, ti has affected the world, and every country in it.
To compare a disaster like this to one in the past to find a scale to rank it on is ignorant. There have been less extreme disasters, and more extreme, but that doesn't mean each one isn't a terrible event. People die, you're right, and life goes on, but we can take measures to prevent the number dead, and the destruction that comes with these events. It's human anture to always better ourselves and way of life.