Speaking at a WHO executive board session on Monday, Dr Tedros said, "I need to be blunt: the world is on the brink of a catastrophic moral failure - and the price of this failure will be paid with lives and livelihoods in the world's poorest countries."
Dr Tedros said a "me-first" approach would be self-defeating because it would push up prices and encourage hoarding.
"Ultimately, these actions will only prolong the pandemic, the restrictions needed to contain it, and human and economic suffering," he added.
And the WHO head called for a full commitment to the global vaccine-sharing scheme Covax, which is due to start rolling out next month.
"My challenge to all member states is to ensure that by the time World Health Day arrives on 7 April, Covid-19 vaccines are being administered in every country, as a symbol of hope for overcoming both the pandemic and the inequalities that lie at the root of so many global health challenges," Dr Tedros said.
As we've seen, certain rich countries have used their economic clout and populist politics to disrupt other nations' vaccine rollout programs. In the USA, Trump-era "America First" policies have been continued by the Biden administration, to the extent that Canada has to source its vaccines from the EU. The UK is rich enough to have bought six doses for every citizen, and is still blocking exports of domestically manufactured doses. (thread)
Maybe poor countries should just pull themselves up by their bootstraps and start manufacturing their own vaccines? Perhaps - but those same rich countries in the north are making that difficult too:
Wealthy countries - including the UK - are blocking proposals to help developing nations increase their vaccine manufacturing capabilities, documents leaked to BBC Newsnight show.
Several poorer countries have asked the World Health Organization to help them.
But richer nations are pushing back on provisions in international law that would enable them to achieve this.
This is according to a leaked copy of the negotiating text of a WHO resolution on the issue.
Among those richer nations are the UK, the US, as well as the European Union.
This isn't over till it's over. Even if we don't care about poor people far away dying of yet another treatable disease, unless we keep the global economy in suspended animation for a few more years international travel means that new variants will keep arriving in the north. From a humanitarian perspective, at the very least we should get enough doses to COVAX to cover all healthcare workers globally.
The arguments about prioritising people based on their vulnerability vs economic contribution vs potential superspreadiness will vary from place to place of course. But I really don't think history will look kindly on privileged vaccine hoarders, whether or not a vaccine-resistant mutation comes back to undo all their gains.