From Science:

Improved medicine
Hungarian-American biochemist Katalin Karikó has contributed to the mRNA technology that made the COVID-19 vaccine possible. French virologist Françoise Barré-Sinoussi first identified HIV (along with Luc Montagnier). Both scientists are alive today, but I would have liked to introduce them in 1983, when Barré- Sinoussi first made her HIV discovery. The collaboration between these two great minds decades ago could have changed the course of multiple pandemics. French physicist Marie Curie (born in Poland) lost her life in 1934 to aplastic anemia caused by radiation exposure. German immunologist Paul Ehrlich, who lived at the same time, first identified the cause of aplastic anemia. I would have liked to introduce these two scientists in time for Ehrlich’s knowledge to prevent Curie’s death. Together, they could have educated the world about the negative effects of radiation, and perhaps even worked on a cure for aplastic anemia.
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