科学者によると、ワクチンの不公平と躊躇により、オミクロンの亜種が発生する可能性が高くなりました。

Vaccine inequity and hesitancy made the Omicron variant more likely, scientists say

(CNN)Many of the world's richest countries have spent the past year hoarding coronavirus vaccines, buying up enough doses to vaccinate their populations several times over and consistently failing to deliver on their promises to share doses with the developing world.
The World Health Organization said the approach was "self-defeating" and "immoral."

https://edition.cnn.com/2021/11/28/world/omicron-coronavirus-variant-vaccine-inequity-intl-cmd/index.html