How Nine Covid-19 Vaccines Work
This tracker followed the early development of selected Covid vaccines through May 2021. It is no longer being updated.
Researchers are testing 90 coronavirus vaccines in clinical trials on humans. Here are explanations about how nine of the leading vaccines work.
Messenger RNA Vaccines
Comirnaty
How the Pfizer-BioNTech Vaccine Works
Cómo funciona la vacuna de Pfizer-BioNTech
The vaccine, known as Comirnaty, has been approved in several countries and authorized for emergency use in many others, including the United States and the European Union.
mRNA-1273
Cómo funciona la vacuna de Moderna
The vaccine, known as mRNA-1273, has been approved in Switzerland and authorized for emergency use in many countries, including the United States and the European Union.
Adenovirus-Based Vaccines
AZD1222
How the Oxford-AstraZeneca Vaccine Works
Cómo funciona la vacuna de Oxford-AstraZeneca
The vaccine, known as AZD1222 or Covishield, is approved in Brazil and authorized for emergency use in dozens of countries.
Ad26.COV2.S
How the Johnson & Johnson Vaccine Works
Cómo funciona la vacuna de Johnson & Johnson
The vaccine, called Ad26.COV2.S, is authorized for emergency use in the United States, the European Union, Canada and other countries.
Sputnik V
(Ad26)
Sputnik V
(Ad5)
How the Gamaleya Vaccine Works
Cómo funciona la vacuna Gamaleya
The vaccine, known as Sputnik V or Gam-Covid-Vac, is a combination of two different Adenoviruses, Ad26 and Ad5. The vaccine is in use in Russia and is authorized for emergency use in dozens of other countries.
Protein-Based Vaccines
NVX-CoV2373
nanoparticle
The vaccine, known as NVX-CoV2373, is in Phase 3 clinical trials. The vaccine has not been authorized by any country.
Inactivated Coronavirus Vaccines
BBIBP-CorV
How the Sinopharm Vaccine Works
Cómo funciona la vacuna de Sinopharm
The vaccine, known as BBIBP-CorV, is approved in China, Bahrain and the United Arab Emirates, and has been authorized for emergency use in several other countries.
CoronaVac
Cómo funciona la vacuna de Sinovac
The vaccine, known as CoronaVac, is approved in China and authorized for emergency use in several other countries.
Covaxin
How Bharat Biotech’s Vaccine Works
The vaccine, known as Covaxin, is authorized for emergency use in India and several other countries.
See the Coronavirus Vaccine Tracker for more information, and for the status of other vaccines in development.