Professor at the Tsinghua's School of Medicine Zhang Linqi speaks next to a screen showing a graphic of the new omicron variant as he introduces new COVID-19 antibody drugs they jointly developed with the Third People's Hospital of Shenzhen and Brii Biosciences during a press briefing at Tsinghua University in Beijing, Thursday, Dec. 9, 2021. Vaccine makers are racing to update their COVID-19 shots against the newest coronavirus threat even before it's clear a change is needed, just in case. (AP Photo/Andy Wong)