Discovering the origins of COVID-19 is a moral imperative and all hypotheses must be explored, the head of the World Health Organization said, in his strongest comments yet that the U.N. body remains committed to finding how the virus arose. "Understanding #COVID19's origins and exploring all hypotheses remains: a scientific imperative, to help us prevent future outbreaks (and) a moral imperative, for the sake of the millions of people who died and those who live with #LongCOVID," Tedros Adhanom Ghebreyesus said on Twitter late on Saturday. He was writing to mark three years since the WHO first used the word "pandemic" to describe the global outbreak of COVID-19. Discovering the origins of COVID-19 is a moral imperative and all hypotheses must be explored, the head of the World Health Organization said, in his strongest comments yet that the U.N. body remains committed to finding how the virus arose. "Understanding #COVID19's origins and exploring all hypotheses remains: a scientific imperative, to help us prevent future outbreaks (and) a moral imperative, for the sake of the millions of people who died and those who live with #LongCOVID," Tedros Adhanom Ghebreyesus said on Twitter late on Saturday.