What does not vary between the countries where apparently there is a big problem is the either careless or deliberate twisting of the data to make it appear far worse than the data justifies. See above or below article links to see facts on this. On demographics, certainly the elderly with preexisting serious medical conditions are far more at risk than those not in that demographic, but there is zero actual evidence that it's more dangerous for them than the flu. The only apparent evidence comes from cooking the numbers fraudulently or carelessly. Which the media is screamingly doing.