You mean beyond the thousands of bodies accounting for over half the world wide deaths from the coronavirus?
But let's go with the clear and obvious: Travel bans and quarantine. At the end of January/Early February the United States, Italy, Australia, Japan and others instituted travels bans to and from China. Fortune has an article dated February 6th with these restrictions by non-EU countries:
https://fortune.com/2020/02/06/count...s-coronavirus/
That's from middle of February it is not a complete list but it does have many examples.
Australia:
Japan:
South Korea:
It goes on. Fact is this isn't just about US vs EU because many countries imposed travel bans with Outside of Italy imposing as a country their own travel ban you don't have the situation of European countries doing it. You DO have airlines restricting or outright canceling their flights to and from China, but country wide or on a EU level? No. The best we had was that most countries in the Schengen area, with the notable exception of France, stopped issuing visas. Brilliant job there.
But no full on travel ban in Europe, no quarantine either. There is no assumption here. Many countries around the world, some of which like South Korea and Japan that have some of the biggest urban sprawls on the planet, took swift and effective measures to contain the outbreak and many of them have.
I made a mistake in using the US as a counter example, simply because it's convenient and well known what the US did and did not do to handle the crisis but the factual situation is that Europe didn't just handle this crisis worse then America, it handled it worse then many other countries including Russia*, Japan, South Korea, Singapore, Australia, Israel and many others.
* Russia could very well be lying about their numbers.