Dozens of coronavirus vaccines entered clinical trials during 2020, and now, a handful have been authorized for
in various countries — meaning the shots can be administered to the public while their developers continue to collect data on their safety and efficacy. Should they meet all the necessary criteria, these vaccines could be fully approved in the future, and in some places, they already have been. emergency use
Here’s a quick guide to the COVID-19 vaccines now in use around the world.
Related: 20 of the worst epidemics and pandemics in history Pfizer-BioNTech
The vaccine developed by Pfizer and German biotechnology company BioNTech is
at preventing COVID-19, a large study found. The vaccine is administered in two doses, given three weeks apart, and it must be stored at minus 94 degrees Fahrenheit (minus 70 degrees Celsius). On Dec. 11, 2020, the Pfizer-BioNTech vaccine became the first COVID-19 vaccine to be 95% effective by the U.S. Food and Drug Administration (FDA). authorized for emergency use
Several other countries have also authorized the vaccine for emergency use, including the U.K., Argentina, Chile and Singapore, and the European Union followed suit on Dec. 21,
. Bahrain, Canada, Saudi Arabia and Switzerland have fully approved the vaccine. The New York Times reported
The shot uses a molecule called mRNA as its base. A molecular cousin of DNA, mRNA contains instructions to build specific proteins; in this case, the mRNA in the vaccine codes for the coronavirus spike protein, a structure that sticks off the virus’s surface and is used to infect human cells. Once inside the body, the vaccine instructs human cells to build this protein, and the immune system learns to recognize and attack it.
The vaccine developed by U.S. biotech company Moderna and the National Institute of Allergy and Infectious Diseases (NIAID) also uses mRNA as its base and is
at preventing COVID-19. Like the Pfizer-BioNTech vaccine, it’s delivered in two doses, but the doses are given four weeks apart, rather than three. Another difference is that the Moderna vaccine can be stored at at minus 4 F (minus 20 C), rather than requiring deep-freezing like the Pfizer shots. estimated to be 94.5% effective
for emergency use on Dec. 18, and Israel and the European Medicines Agency, an agency of the European Union, both authorized the shots for emergency use in January, according to the Times. Canada fully approved the vaccine on Dec. 23. authorized the Moderna vaccine Oxford-AstraZeneca
and pharmaceutical company AstraZeneca is estimated to be about 70% effective at preventing COVID-19 — that said, in clinical trials, adjusting the dose seemed to boost this efficacy. developed by Oxford University
In people given two full-size doses, spaced 28 days apart, the vaccine was about 62% effective; in those given a half-dose followed by a full dose, the vaccine was 90% effective,
. However, clinical trial participants who got half-doses did so by mistake, and some scientists have questioned whether those early results are representative. according to early analyses
and Argentina authorized the Oxford-AstraZeneca vaccine for emergency use in late December, and India and Mexico authorized the vaccine for emergency use in January, according to the Times. The shots contain a weakened version of adenovirus, a common cold virus that naturally infects chimpanzees. Scientists modified the virus so it cannot replicate in human cells and then added genes that code for the coronavirus spike protein. Inside the body, the vaccine enters cells and delivers these spike protein genes, which the cells use to build the spike protein itself. The presence of spike proteins triggers an immune response. The U.K.
Pfizer-BioNTech vaccines being placed in a freezer at the University Hospital in Brussels, Belgium on December 26, 2020. (Image credit: Nicolas Maeterlinck – Pool#OM/Getty Images) Sinopharm (Beijing Institute of Biological Products)
Sinopharm, the state-owned China National Pharmaceutical Group, and the Beijing Institute of Biological Products developed a vaccine from an inactivated coronavirus, meaning a modified version of SARS-CoV-2 that cannot replicate. In late December,
that the vaccine, called BBIBP-CorV, is more than 79% effective, according to preliminary data from late-stage clinical trials — that said, the company has not published said data. Sinopharm announced
In the summer of 2020, China gave Sinopharm authorization to vaccinate construction workers, diplomats and students with one of its two COVID-19 vaccine candidates, including BBIBP-CorV,
. Nearly 1 million people had received the vaccines by November, according to the company’s chairman. Live Science previously reported
The United Arab Emirates authorized BBIBP-CorV for emergency use in September and then fully
in December. Bahrain and China also fully approved the vaccine in December, and Egypt authorized it for emergency use in January 2021, approved the vaccine . The vaccine is given in two doses spaced three weeks apart. the Times reported Sinopharm (Wuhan Institute of Biological Products)
Sinopharm’s second vaccine candidate, developed by the Wuhan Institute of Biological Products, also uses an inactivated coronavirus as its base. The vaccine has been authorized for emergency use in China and the U.A.E., but little is known about its efficacy.
, in collaboration with the Beijing Institute of Biotechnology, developed a COVID-19 vaccine using a weakened adenovirus, but one that naturally infects humans, not chimpanzees. Late-stage clinical trials with the vaccine are still ongoing, and its efficacy is not yet known. The shot is given in a single dose. CanSino Biologics
In June 2020, the CanSino vaccine was given approval to be used by China’s military,
. according to Reuters Sinovac
The Chinese company Sinovac Biotech developed a vaccine from an inactivated version of SARS-CoV-2. The vaccine, called CoronaVac, is given in two doses 14 days apart,
. China authorized the vaccine for emergency use in July. Live Science previously reported
Estimates vary as to how well the vaccine protects against COVID-19, and an official estimate has not yet been issued. One clinical trial in Brazil suggested that the vaccine was about 78% effective in one small subgroup of patients, but across all people, the efficacy may be closer to 63%,
, a Brazilian news outlet. according to Estadão Bharat Biotech
The Indian company Bharat Biotech, along with the Indian Council of Medical Research and the National Institute of Virology developed a vaccine from an inactivated coronavirus, called Covaxin,
. The vaccine is given in two doses, spaced four weeks apart, and has been authorized for emergency use in India. It’s efficacy has not been publicly reported. the Times reported Gamaleya Research Institute
The Russia Ministry of Health’s Gamaleya Research Institute developed a coronavirus vaccine candidate called Sputnik V, in reference to the world’s first artificial satellite, launched during the
, space race . The vaccine contains two common cold viruses, or adenoviruses, that have been modified so they don’t replicate in humans; the modified viruses also contain genes that code for the coronavirus’s spike protein. Live Science previously reported
In November, Russia announced that the vaccine is more than 91.4% effective in preventing COVID-19, according to early data from clinical trials. (Full details of the trials have yet to be published in a scientific journal.)
In the same month, Russia began offering the vaccine to its citizens as part of a mass vaccination campaign, according to The New York Times. Russia had already approved the vaccine for limited use in August, when very little data from human trials was available,
Live Science previously reported.
Since November, Belarus, Argentina and Serbia have also authorized the vaccine for emergency use, the Times reported.
In October 2020, Russia granted “regulatory approval” to a second vaccine, one developed by the Vector Institute, a Russian biological research center,
. The vaccine contains coronavirus peptides, which are small portions of proteins found in the virus. Like Sputnik V, the vaccine earned approval in Russia before large-scale clinical trials had been conducted. As of now, its efficacy is still unknown. according to CNBC
Originally published on Live Science.