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Dec. 31, 2019
The Wuhan Municipal Health Commission reports 27 unusual cases of pneumonia.
Jan. 10, 2020
The first genome sequence of the novel coronavirus is made publicly available.
Moderna announces plans to develop and test a messenger RNA (mRNA) vaccine against the novel coronavirus.
CanSino Biologics and Moderna each start Phase 1 clinical trials of their vaccines, marking the first human studies of adenoviral vector and mRNA COVID-19 vaccines.
More than 1 million cases worldwide
University of Oxford researchers begin a Phase 1 trial of their adenoviral vector vaccine, which is later licensed to AstraZeneca.
The first participant in the US is dosed in the Phase 1 trial of Pfizer and BioNTech’s mRNA vaccine.
Moderna announces preliminary Phase 1 data showing its mRNA vaccine is safe and can induce antibodies against the virus.
More than 10 million cases worldwide
China approves CanSino’s adenoviral vector vaccine for military use.
Russia approves an adenoviral vector vaccine despite a lack of peerreviewed data in humans and before conducting a Phase 3 trial.
A Phase 3 study of AstraZeneca’s adenoviral vector vaccine is put on hold—and not restarted until late October—after a UK participant experiences a serious adverse reaction.
More than 50 million cases worldwide
Pfizer says initial data from a Phase 3 study show its mRNA vaccine is 90% efficacious—a figure that is later increased to 95%.
Moderna says initial data from a Phase 3 study show its mRNA vaccine is 94.5% effective.
AstraZeneca reports positive but confusing initial Phase 3 data for its adenoviral vector vaccine.
The UK grants emergency authorization for Pfizer and BioNTech’s mRNA vaccine.
The US Food and Drug Administration grants an emergency use authorization (EUA) for Pfizer’s mRNA vaccine, making it the first authorized COVID-19 vaccine in the US.
The FDA grants an EUA for Moderna’s mRNA vaccine.
More than 80 million cases worldwide
The UK grants emergency authorization for AstraZeneca’s adenoviral vector vaccine.
Source: COVID-19 Dashboard by the Center for Systems Science and Engineering at Johns Hopkins University (case counts).