COVID-19 vaccine

For vaccine development and distribution, see Development of COVID-19 vaccines and Deployment of COVID-19 vaccines.

Map of countries by approval status

  Approved for general use, mass vaccination underway

  EUA (or equivalent) granted, mass vaccination underway

  EUA granted, limited vaccination

  Approved for general use, mass vaccination planned

  EUA granted, mass vaccination planned

  EUA pending

Percentage of population that has been vaccinated against COVID-19 worldwide, as of February 6, 2021.

  Over 30%

  10-29%

  Less than 10% or no data

A COVID‑19 vaccine is a vaccine intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), the virus causing Coronavirus disease 2019 (COVID‑19). Prior to the COVID‑19 pandemic, work to develop a vaccine against coronavirus diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) established knowledge about the structure and function of coronaviruses; this knowledge enabled accelerated development of various vaccine technologies during early 2020.

As of February 2021, 66 vaccine candidates are in clinical research, including 17 in Phase I trials, 23 in Phase I–II trials, 6 in Phase II trials, and 20 in Phase III trials. Trials for four other candidates were terminated. In Phase III trials, several COVID‑19 vaccines demonstrate efficacy as high as 95% in preventing symptomatic COVID‑19 infections. As of February 2021, ten vaccines are authorized by at least one national regulatory authority for public use: two RNA vaccines (the Pfizer–BioNTech vaccine and the Moderna vaccine), four conventional inactivated vaccines (BBIBP-CorV from Sinopharm, BBV152 from Bharat Biotech, CoronaVac from Sinovac, and WIBP from Sinopharm), three viral vector vaccines (Sputnik V from the Gamaleya Research Institute, the Oxford–AstraZeneca vaccine, and Ad5-nCoV from CanSino Biologics), and one peptide vaccine (EpiVacCorona from the Vector Institute).

Many countries have implemented phased distribution plans that prioritize those at highest risk of complications, such as the elderly, and those at high risk of exposure and transmission, such as healthcare workers. As of 5 February 2021, 123.54 million doses of COVID‑19 vaccine have been administered worldwide based on official reports from national health agencies. Pfizer, Moderna, and AstraZeneca predicted a manufacturing capacity of 5.3 billion doses in 2021, which could be used to vaccinate about 3 billion people (as the vaccines require two doses for a protective effect against COVID‑19). By December, more than 10 billion vaccine doses had been preordered by countries, with about half of the doses purchased by high-income countries comprising 14% of the world's population.

Background

A US airman receiving a COVID-19 vaccine.

Prior to COVID‑19, a vaccine for an infectious disease had never been produced in less than several years—and no vaccine existed for preventing a coronavirus infection in humans. However, vaccines have been produced against several animal diseases caused by coronaviruses, including (as of 2003) infectious bronchitis virus in birds, canine coronavirus, and feline coronavirus. Previous projects to develop vaccines for viruses in the family Coronaviridae that affect humans have been aimed at severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Vaccines against SARS and MERS have been tested in non-human animals.

According to studies published in 2005 and 2006, the identification and development of novel vaccines and medicines to treat SARS was a priority for governments and public health agencies around the world at that time. As of 2020, there is no cure or protective vaccine proven to be safe and effective against SARS in humans. There is also no proven vaccine against MERS. When MERS became prevalent, it was believed that existing SARS research may provide a useful template for developing vaccines and therapeutics against a MERS-CoV infection. As of March 2020, there was one (DNA based) MERS vaccine which completed Phase I clinical trials in humans and three others in progress, all being viral-vectored vaccines: two adenoviral-vectored (ChAdOx1-MERS, BVRS-GamVac) and one MVA-vectored (MVA-MERS-S).

The urgency to create a vaccine for COVID‑19, led to compressed schedules that shortened the standard vaccine development timeline, in some cases combining clinical trial steps over months, a process typically conducted sequentially over years. Multiple steps along the entire development path are evaluated, including the level of acceptable toxicity of the vaccine (its safety), targeting vulnerable populations, the need for vaccine efficacy breakthroughs, the duration of vaccination protection, special delivery systems (such as oral or nasal, rather than by injection), dose regimen, stability and storage characteristics, emergency use authorization before formal licensing, optimal manufacturing for scaling to billions of doses, and dissemination of the licensed vaccine. Timelines for conducting clinical research – normally a sequential process requiring years – are being compressed into safety, efficacy, and dosing trials running simultaneously over months, potentially compromising safety assurance. As an example, Chinese vaccine developers and the government Chinese Center for Disease Control and Prevention began their efforts in January 2020, and by March were pursuing numerous candidates on short timelines, with the goal to showcase Chinese technology strengths over those of the United States, and to reassure the Chinese people about the quality of vaccines produced in China.

Planning and development

Since early 2020, vaccine development has been expedited via unprecedented collaboration in the multinational pharmaceutical industry and between governments. According to the Coalition for Epidemic Preparedness Innovations (CEPI), the geographic distribution of COVID‑19 vaccine development puts North American entities having about 40% of the activity compared to 30% in Asia and Australia, 26% in Europe, and a few projects in South America and Africa.

There have been several unique challenges with COVID-19 vaccine development. The rapid development and urgency of producing a vaccine for the COVID‑19 pandemic may increase the risks and failure rate of delivering a safe, effective vaccine. Additionally, research at universities is obstructed by physical distancing and closing of laboratories.

Vaccines must progress through several phases of clinical trials to test for safety, immunogenicity, effectiveness, dose levels and adverse effects of the candidate vaccine. Vaccine developers have to invest resources internationally to find enough participants for Phase II–III clinical trials when the virus has proved to be a "moving target" of changing transmission rate across and within countries, forcing companies to compete for trial participants; clinical trial organizers may encounter people unwilling to be vaccinated due to vaccine hesitancy or disbelieving the science of the vaccine technology and its ability to prevent infection. Even as new vaccines are developed during the COVID‑19 pandemic, licensure of COVID‑19 vaccine candidates requires submission of a full dossier of information on development and manufacturing quality.

Organizations

Internationally, the Access to COVID-19 Tools Accelerator is a G20 and World Health Organization initiative announced in April 2020. It is a cross-discipline support structure to enable partners to share resources and knowledge. It comprises four pillars, each managed by two to three collaborating partners: Vaccines (also called "COVAX"), Diagnostics, Therapeutics, and Health Systems Connector. The WHO's April 2020 "R&D Blueprint (for the) novel Coronavirus" documented a "large, international, multi-site, individually randomized controlled clinical trial" to allow "the concurrent evaluation of the benefits and risks of each promising candidate vaccine within 3–6 months of it being made available for the trial." The WHO vaccine coalition will prioritize which vaccines should go into Phase II and III clinical trials, and determine harmonized Phase III protocols for all vaccines achieving the pivotal trial stage.

National governments have also been involved in vaccine development. Canada announced funding for 96 research vaccine research projects at Canadian companies and universities, with plans to establish a "vaccine bank" that could be used if another coronavirus outbreak occurs, and to support clinical trials and develop manufacturing and supply chains for vaccines. China provided low-rate loans to a vaccine developer through its central bank and "quickly made land available for the company" to build production plants. Three Chinese vaccine companies and research institutes are supported by the government for financing research, conducting clinical trials, and manufacturing. Great Britain formed a COVID‑19 vaccine task force in April 2020 to stimulate local efforts for accelerated development of a vaccine through collaborations of industry, universities, and government agencies. It encompassed every phase of development from research to manufacturing. In the United States, the Biomedical Advanced Research and Development Authority (BARDA), a federal agency funding disease-fighting technology, announced investments to support American COVID‑19 vaccine development and manufacture of the most promising candidates. In May 2020, the government announced funding for a fast-track program called Operation Warp Speed.

Large pharmaceutical companies with experience in making vaccines at scale, including Johnson & Johnson, AstraZeneca, and GlaxoSmithKline (GSK), formed alliances with biotechnology companies, governments, and universities to accelerate progression to an effective vaccine.

History

This section is an excerpt from History of COVID-19 vaccine development.[edit]

COVID‑19 vaccine research samples in a NIAID lab freezer (30 January 2020)

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the virus that causes COVID-19, was isolated in late 2019. Its genetic sequence was published on 11 January 2020, triggering an urgent international response to prepare for an outbreak and hasten the development of a preventive COVID-19 vaccine. Since 2020, vaccine development has been expedited via unprecedented collaboration in the multinational pharmaceutical industry and between governments. By June 2020, tens of billions of dollars were invested by corporations, governments, international health organizations, and university research groups to develop dozens of vaccine candidates and prepare for global vaccination programs to immunize against COVID‑19 infection. According to the Coalition for Epidemic Preparedness Innovations (CEPI), the geographic distribution of COVID‑19 vaccine development shows North American entities to have about 40% of the activity, compared to 30% in Asia and Australia, 26% in Europe, and a few projects in South America and Africa.

In February 2020, the World Health Organization (WHO) said it did not expect a vaccine against SARS‑CoV‑2 to become available in less than 18 months. Virologist Paul Offit commented that, in hindsight, the development of a safe and effective vaccine within 11 months was a remarkable feat. The rapidly growing infection rate of COVID‑19 worldwide during 2020 stimulated international alliances and government efforts to urgently organize resources to make multiple vaccines on shortened timelines, with four vaccine candidates entering human evaluation in March (see COVID-19 vaccine § Trial and authorization status).

On 24 June 2020, China approved the CanSino vaccine for limited use in the military and two inactivated virus vaccines for emergency use in high-risk occupations. On 11 August 2020, Russia announced the approval of its Sputnik V vaccine for emergency use, though one month later only small amounts of the vaccine had been distributed for use outside of the phase 3 trial.

The Pfizer–BioNTech partnership submitted an Emergency Use Authorization (EUA) request to the U.S. Food and Drug Administration (FDA) for the mRNA vaccine BNT162b2 (active ingredient tozinameran) on 20 November 2020. On 2 December 2020, the United Kingdom's Medicines and Healthcare products Regulatory Agency (MHRA) gave temporary regulatory approval for the Pfizer–BioNTech vaccine, becoming the first country to approve the vaccine and the first country in the Western world to approve the use of any COVID‑19 vaccine. As of 21 December 2020, many countries and the European Union had authorized or approved the Pfizer–BioNTech COVID‑19 vaccine. Bahrain and the United Arab Emirates granted emergency marketing authorization for the Sinopharm BIBP vaccine. On 11 December 2020, the FDA granted an EUA for the Pfizer–BioNTech COVID‑19 vaccine. A week later, they granted an EUA for mRNA-1273 (active ingredient elasomeran), the Moderna vaccine.

On 31 March 2021, the Russian government announced that they had registered the first COVID‑19 vaccine for animals. Named Carnivac-Cov, it is an inactivated vaccine for carnivorous animals, including pets, aimed at preventing mutations that occur during the interspecies transmission of SARS-CoV-2.

In October 2022, China began administering an oral vaccine developed by CanSino Biologics using its adenovirus model.

Despite the availability of mRNA and viral vector vaccines, worldwide vaccine equity has not been achieved. The ongoing development and use of whole inactivated virus (WIV) and protein-based vaccines has been recommended, especially for use in developing countries, to dampen further waves of the pandemic.

Vaccine types

Conceptual diagram showing three vaccine types for forming SARS‑CoV‑2 proteins to prompt an immune response: (1) RNA vaccine, (2) subunit vaccine, (3) viral vector vaccine

As of January 2021, nine different technology platforms – with the technology of numerous candidates remaining undefined – are under research and development to create an effective vaccine against COVID‑19. Most of the platforms of vaccine candidates in clinical trials are focused on the coronavirus spike protein and its variants as the primary antigen of COVID‑19 infection. Platforms being developed in 2020 involved nucleic acid technologies (nucleoside-modified messenger RNA and DNA), non-replicating viral vectors, peptides, recombinant proteins, live attenuated viruses, and inactivated viruses.

Many vaccine technologies being developed for COVID‑19 are not like vaccines already in use to prevent influenza, but rather are using "next-generation" strategies for precision on COVID‑19 infection mechanisms. Vaccine platforms in development may improve flexibility for antigen manipulation and effectiveness for targeting mechanisms of COVID‑19 infection in susceptible population subgroups, such as healthcare workers, the elderly, children, pregnant women, and people with existing weakened immune systems.

COVID‑19 vaccine technology platforms, January 2021

Molecular platform	Total number of candidates	Number of candidates in human trials	Number authorized in at least one country	Number of countries authorized
Non-replicating viral vector	35	4	3	32
RNA-based	36	3	2	32
Inactivated virus	19	5	3	14
Protein subunit	80	4	1	2
DNA-based	23	2	0	0
Virus-like particle	19	1	0	0
Replicating viral vector	23	0	0	0
Live attenuated virus	4	0	0	0

RNA vaccines

Diagram of the operation of an RNA vaccine. Messenger RNA contained in the vaccine enters cells and is translated into foreign proteins, which trigger an immune response.

An RNA vaccine contains RNA which, when introduced into a tissue, acts as messenger RNA (mRNA) to cause the cells to build the foreign protein and stimulate an adaptive immune response which teaches the body how to identify and destroy the corresponding pathogen or cancer cells. RNA vaccines often, but not always, use nucleoside-modified messenger RNA. The delivery of mRNA is achieved by a coformulation of the molecule into lipid nanoparticles which protect the RNA strands and help their absorption into the cells.

RNA vaccines were the first COVID-19 vaccines to be authorized in the United States and the European Union. As of January 2021, authorized vaccines of this type are the Pfizer-BioNTech COVID‑19 vaccine and the Moderna COVID-19 vaccine.

Adenovirus vector vaccines

These vaccines are examples of non-replicating viral vectors, using an adenovirus shell containing DNA that encodes a SARS‑CoV‑2 protein. The viral vector-based vaccines against COVID-19 are non-replicating, meaning that they do not make new virus particles, but rather produce only the antigen which elicits a systemic immune response.

As of January 2021, authorized vaccines of this type are the British Oxford–AstraZeneca COVID-19 vaccine, Russian Sputnik V, and Chinese Convidicea. Vaccines in clinical trials include Johnson & Johnson's Ad26.COV2.S.

Inactivated virus vaccines

Inactivated vaccines consist of virus particles that have been grown in culture and then are killed using a method such as heat or formaldehyde to lose disease producing capacity, while still stimulating an immune response.

As of January 2021, authorized vaccines of this type are the Chinese CoronaVac and BBIBP-CorV as well as the Indian Covaxin. Vaccines in clinical trials include the Valneva COVID-19 vaccine.

Subunit vaccines

Subunit vaccines present one or more antigens without introducing whole pathogen particles. The antigens involved are often protein subunits, but can be any molecule that is a fragment of the pathogen.

As of January 2021, the only authorized vaccine of this type is the peptide vaccine EpiVacCorona. Vaccines in clinical trials include the Novavax COVID-19 vaccine and RBD-Dimer. The V451 vaccine was previously in clinical trials, which were terminated because it was found that the vaccine may potentially cause incorrect results for subsequent HIV testing.

Other types

Additional types of vaccines that are in clinical trials include multiple DNA plasmid vaccines, at least two lentivirus vector vaccines, a virus-like particle, and a vesicular stomatitis virus displaying the SARS‑CoV‑2 spike protein.

Scientists investigated whether existing vaccines for unrelated conditions could prime the immune system and lessen the severity of COVID‑19 infection. There is experimental evidence that the BCG vaccine for tuberculosis has non-specific effects on the immune system, but no evidence that this vaccine is effective against COVID‑19.

Trial and authorization status

Phase I trials test primarily for safety and preliminary dosing in a few dozen healthy subjects, while Phase II trials – following success in Phase I – evaluate immunogenicity, dose levels (efficacy based on biomarkers) and adverse effects of the candidate vaccine, typically in hundreds of people. A Phase I–II trial consists of preliminary safety and immunogenicity testing, is typically randomized, placebo-controlled, while determining more precise, effective doses. Phase III trials typically involve more participants at multiple sites, include a control group, and test effectiveness of the vaccine to prevent the disease (an "interventional" or "pivotal" trial), while monitoring for adverse effects at the optimal dose. Definition of vaccine safety, efficacy, and clinical endpoints in a Phase III trial may vary between the trials of different companies, such as defining the degree of side effects, infection or amount of transmission, and whether the vaccine prevents moderate or severe COVID‑19 infection.

A clinical trial design in progress may be modified as an "adaptive design" if accumulating data in the trial provide early insights about positive or negative efficacy of the treatment. Adaptive designs within ongoing Phase II–III clinical trials on candidate vaccines may shorten trial durations and use fewer subjects, possibly expediting decisions for early termination or success, avoiding duplication of research efforts, and enhancing coordination of design changes for the Solidarity trial across its international locations.

List of authorized and approved vaccines

National regulatory authorities have granted emergency use authorizations for nine vaccines. Three of those have been approved for emergency or full use by WHO-recognized stringent regulatory authorities (SRAs).

Vaccines authorized for emergency use or approved for full use

Vaccine, developers/sponsors	Country of Origin	Technology	Current phase (participants)	Completed phase (participants)	Authorization
BBIBP-CorV Sinopharm: Beijing Institute of Biological Products, Wuhan Institute of Biological Products	China	Inactivated SARS‑CoV‑2 vaccine (vero cells)	Phase III (48,000) Randomized, double-blind, parallel placebo-controlled, to evaluate safety and protective efficacy. Sinopharm's internal analysis indicated a 79% efficacy. Jul 2020 – Jul 2021, United Arab Emirates, Bahrain, Jordan, Argentina, Morocco, Peru	Phase I–II (320) Neutralizing antibodies at day 14 after two injections Apr 2020 – Jun 2020, China	Emergency (10) Cambodia Egypt Hungary Iraq Jordan Laos Morocco Pakistan Peru Serbia Full (4) Bahrain China Seychelles United Arab Emirates
Sputnik V COVID-19 vaccine Gamaleya Research Institute of Epidemiology and Microbiology	Russia	Adenovirus vector vaccine (recombinant adenovirus type 5 and 26 vector)	Phase III (40,000) Randomized double-blind, placebo-controlled to evaluate efficacy, immunogenicity, and safety. Interim analysis from the trial was published in The Lancet, indicating 91.6% efficacy without unusual side effects. Aug 2020 – May 2021, Russia, Belarus, India, Venezuela, UAE	Phase I–II (76) Neutralizing antibody and T cell responses. Jun 2020 – Sep 2020, Russia	Emergency (24) Algeria Argentina Armenia Belarus Bolivia Guinea Iran Kazakhstan Laos Lebanon Mexico Mongolia Myanmar Nicaragua Pakistan Palestine Paraguay Republika Srpska Russia Serbia Tunisia United Arab Emirates Uruguay Venezuela Full (2) Hungary Turkmenistan
Pfizer–BioNTech COVID-19 vaccine (Comirnaty) BioNTech, Pfizer	United States, Germany	RNA vaccine (modRNA encapsulated in lipid nanoparticles)	Phase III (43,448) Randomized, placebo-controlled. Positive results from an interim analysis were announced on 18 November 2020 and published on 10 December 2020 reporting an overall efficacy of 95%. Jul 2020 – Nov 2020, Germany, United States	Phase I–II (45) Strong RBD-binding IgG and neutralizing antibody response peaked 7 days after a booster dose, robust CD4+ and CD8+ T cell responses, undetermined durability. May 2020 – ?	Emergency (25) Albania Argentina Bahrain Canada Chile Colombia Costa Rica Ecuador Iraq Israel Jordan Kuwait Mexico New Zealand Oman Panama Philippines Qatar Singapore Switzerland UAE UK US Vatican City WHO Full (9) Australia EU Faroe Islands Greenland Iceland Malaysia Norway Saudi Arabia Serbia
Moderna COVID-19 vaccine Moderna, NIAID, BARDA, CEPI	United States	RNA vaccine (modRNA encapsulated in lipid nanoparticles)	Phase III (30,000) Interventional; randomized, placebo-controlled study for efficacy, safety, and immunogenicity. Positive results from an interim analysis were announced on 15 November 2020 and published on 30 December 2020 reporting an overall efficacy of 94%. Jul 2020 – Oct 2022, United States	Phase I–II (720) Dose-dependent neutralizing antibody response on two-dose schedule; undetermined durability. Mar 2020 – Nov 2021, United States	Emergency (7) Canada Israel Saudi Arabia Singapore Switzerland UK US Full (5) EU Faroe Islands Greenland Iceland Norway
Oxford–AstraZeneca COVID-19 vaccine University of Oxford, AstraZeneca, CEPI	United Kingdom	Adenovirus vector vaccine (modified chimpanzee adenovirus vector, ChAdOx1)	Phase III (30,000) Interventional; randomized, placebo-controlled study for efficacy, safety, and immunogenicity. Positive results from an interim analysis of four ongoing trials were announced on 23 November 2020, and published on 8 December 2020. Overall efficacy was 70%, ranging from 62% to 90% with different dosing regimens, with a peer-reviewed safety profile. May 2020 – Aug 2021, Brazil (5,000), United Kingdom, India	Phase I–II (543) Spike-specific antibodies at day 28; neutralizing antibodies after a booster dose at day 56.	Emergency (19) Argentina Bahrain Bangladesh Brazil Dominican Republic Ecuador El Salvador India Iraq Mexico Myanmar Nepal Pakistan Philippines Saudi Arabia Sri Lanka Thailand UK Vietnam Full (2) EU South Korea
EpiVacCorona Vector Institute	Russia	Peptide vaccine	Phase III (40,000) Randomized double-blind, placebo-controlled to evaluate efficacy, immunogenicity, and safety Nov 2020 – Dec 2021, Russia	Phase I–II (100) Simple, blind, placebo-controlled, randomized study of safety, reactogenicity and immunogenicity Jul 2020 – Sep 2020, Russia	Emergency (1) Russia Full (1) Turkmenistan
CoronaVac Sinovac	China	Inactivated SARS‑CoV‑2 vaccine	Phase III (33,620) Double-blind, randomized, placebo-controlled to evaluate efficacy and safety. Positive results from an interim analysis of a small sample were announced by Turkey on 24 December 2020, with an efficacy of 91%. Additional results were announced by Indonesia on 11 January, with an overall efficacy of 65%. The vaccine was 50% effective at preventing symptomatic infections in a Brazilian trial. Jul 2020 – Oct 2021, Brazil (15,000); Aug 2020 – Jan 2021, Indonesia (1,620); Chile (3,000); Turkey (13,000)	Phase II (600) Immunogenicity eliciting 92% seroconversion at lower dose and 98% at higher dose after 14 days May 2020 – July 2020, China	Emergency (9) Azerbaijan Bolivia Brazil Chile Colombia Indonesia Laos Turkey Uruguay Full (1) China
Ad5-nCoV (Convidicea) CanSino Biologics, Beijing Institute of Biotechnology of the Academy of Military Medical Sciences	China	Adenovirus vector vaccine (recombinant adenovirus type 5 vector)	Phase III (40,000) Global multi-center, randomized, double-blind, placebo-controlled to evaluate efficacy, safety and immunogenicity. In February 2021, interim analysis from global trials showed an efficacy of 65.7% against moderate cases of COVID-19 and 90.98% efficacy against severe cases. Mar–Dec 2020, China; Sep 2020 – Dec 2021, Pakistan; Sep 2020 – Nov 2020, Russia, China, Argentina, Chile; Mexico; Pakistan; Saudi Arabia	Phase II (508) Neutralizing antibody and T cell responses	Emergency (1) China (early) Full (0) None
BBV152 (Covaxin) Bharat Biotech, Indian Council of Medical Research	India	Inactivated SARS‑CoV‑2 vaccine	Phase III (25,800) Randomised, observer-blinded, placebo-controlled Nov 2020 – Mar 2021, India	Phase I (375) Dose-dependent neutralizing antibody response on two-dose schedule. Pending Phase II reports.	Emergency (1) India (monitored) Full (0) None

Vaccine candidates

COVID‑19 candidate vaccines in Phase I–III trials

Vaccine candidates, developers, and sponsors	Country of Origin	Technology	Current phase (participants) design	Completed phase (participants) Immune response	Pending authorization
Ad26.COV2.S Janssen Pharmaceutica (Johnson & Johnson), BIDMC	Netherlands, United States	Adenovirus vector vaccine (adenovirus serotype 26)	Phase III (40,000) Randomized, double-blinded, placebo-controlled Positive results from an interim analysis were announced on 29 January 2021. Jul 2020 – 2023, United States, Argentina, Brazil, Chile, Colombia, Mexico, Peru, the Philippines, South Africa, Ukraine	Phase I–II (1,045) Neutralizing-antibody titers against wild-type virus were detected in 90% or more of all participants on day 29 after the first vaccine dose and reached 100% by day 57 with a further increase in titers, regardless of vaccine dose or age group. Titers remained stable until at least day 71.	Emergency (4) Canada EU: EMA South Africa US: FDA Full (0) None
NVX-CoV2373 Novavax, CEPI	United States	Subunit vaccine (SARS‑CoV‑2 recombinant spike protein nanoparticle with adjuvant)	Phase III (45,000) Randomised, observer-blinded, placebo-controlled trial Sep 2020 – Jan 2021, UK (15,000); Dec 2020 – Mar 2021, US, Mexico, (30,000)	Phase I–II (131) IgG and neutralizing antibody response with adjuvant after booster dose.	Emergency (2) Canada EU: EMA Full (0) None
ZF2001 (RBD-Dimer) Anhui Zhifei Longcom Biopharmaceutical Co. Ltd.	China	Subunit vaccine (recombinant)	Phase III (29,000) Randomized, double-blind, placebo-controlled Dec 2020 – Apr 2022, China, Ecuador, Indonesia, Malaysia, Pakistan, Uzbekistan	Phase II (900) Interventional; randomized, double-blind, placebo-controlled Jun 2020 – Sep 2021, Chongqing
Zorecimeran (CVnCoV) CureVac, CEPI	Germany	RNA vaccine (unmodified RNA)	Phase III (36,500) Phase 2b/3: Multicenter efficacy and safety trial in adults Nov 2020 – ?, Argentina, Belgium, Colombia, Dominican Republic, France, Germany, Mexico, Netherlands, Panama, Peru, Spain	Phase I–II (944) Phase I (284): Partially blind, controlled, dose-escalation to evaluate safety, reactogenicity and immunogenicity. Phase IIa (660):Partially observer-blind, multicenter, controlled, dose-confirmation. Jun 2020 – Oct 2021, Belgium (phase I), Germany (phase I), Panama (phase IIa), Peru (phase IIa)
ZyCoV-D Cadila Healthcare	India	DNA vaccine (plasmid expressing SARS‑CoV‑2 S protein)	Phase III (26,000) Jan 2021 – ?, India	Phase I–II (1,000) Interventional; randomized, double-blind, placebo-controlled Jul 2020 – Jan 2021, India
CoVLP Medicago, GSK	Canada	Virus-like particles (recombinant, plant-based with AS03)	Phase II–III (30,612) Event-driven, randomized, observer blinded, placebo-controlled Nov 2020 – Apr 2022, Canada	Phase I (180) Neutralizing antibodies at day 42 after the first injection (day 21 after the second injection) were at levels 10x that of COVID-19 survivors.
IIBR-100 (Brilife) The Israel Institute for Biological research	Israel	Vesicular stomatitis vector vaccine (recombinant)	Phase II (1,000) Dec 2020 – spring 2021, Israel	Phase I (80) Subjects (18–55 years old) randomly receiving a single administration of IIBR-100 at the low, mid, or high dose, or saline, or two administrations at a low dose, or saline, 28 days apart. Oct–Nov 2020, Israel
FINLAY-FR-2 (SOBERANA 02) Instituto Finlay de Vacunas		Conjugate vaccine	Phase II (910) Allocation: Randomized controlled trial. Masking: Double Blind. Control group: Placebo. Study design: Parallel. Jan–Mar 2021, Cuba	Phase I (40) Allocation: Non-randomized controlled trial. Masking: Open. Control group: Uncontrolled. Study design: Adaptive, sequential Nov 2020 – Jan 2021, Cuba
INO-4800 Inovio, CEPI, Korea National Institute of Health, International Vaccine Institute		DNA vaccine (plasmid delivered by electroporation)	Phase I–II (40) Apr–Nov 2020, United States, South Korea	Preclinical Pending Phase I report.
Unnamed Chinese Academy of Medical Sciences		Inactivated SARS‑CoV‑2 vaccine	Phase I–II (942) Randomized, double-blinded, single-center, placebo-controlled Jun 2020 – Sep 2021, Chengdu	Preclinical
AG0301-COVID‑19 AnGes Inc., AMED		DNA vaccine (plasmid)	Phase I–II (30) Non-randomized, single-center, two doses Jun 2020 – Jul 2021, Osaka	Preclinical
Lunar-COV19/ARCT-021 Arcturus Therapeutics		RNA vaccine	Phase I–II (92) Randomized, double-blinded Aug 2020 – ?, Singapore	Preclinical
VLA2001 Valneva		Inactivated SARS‑CoV‑2 vaccine	Phase I–II (150) Randomized, multi-center, double-blinded Dec 2020 – Feb 2021, United Kingdom	Preclinical
COVID‑19/aAPC Shenzhen Genoimmune Medical Institute		Lentiviral vector vaccine (with minigene modifying aAPCs)	Phase I (100) Mar 2020 – 2023, Shenzhen	Preclinical
LV-SMENP-DC Shenzhen Genoimmune Medical Institute		Lentiviral vector vaccine (with minigene modifying DCs)	Phase I (100) Mar 2020 – 2023, Shenzhen	Preclinical
LNP-nCoVsaRNA MRC clinical trials unit at Imperial College London		RNA vaccine	Phase I (105) Randomized trial, with dose escalation study (15) and expanded safety study (at least 200) Jun 2020 – Jul 2021, United Kingdom	Preclinical
GRAd-COV2 ReiThera, Lazzaro Spallanzani National Institute for Infectious Diseases		Adenovirus vector vaccine (modified chimpanzee adenovirus vector, GRAd)	Phase I (90) Subjects (two groups: 18–55 and 65–85 years old) randomly receiving one of three escalating doses of GRAd-COV2 or a placebo, then monitored over a 24-week period. 93% of subjects who received GRAd-COV2 developed anti-bodies. Aug–Dec 2020, Rome	Preclinical
GX-19 Genexine consortium, International Vaccine Institute		DNA vaccine	Phase I (40) Jun 2020 – Jun 2022, Seoul	Preclinical
SCB-2019 Clover Biopharmaceuticals, GSK, CEPI		Subunit vaccine (Spike protein trimeric subunit with AS03)	Phase I (150) Jun 2020 – Mar 2021, Perth	Preclinical
COVAX-19 Vaxine Pty Ltd		Subunit vaccine (recombinant protein)	Phase I (40) Jun 2020 – Jul 2021, Adelaide	Preclinical
Unnamed PLA Academy of Military Science, Walvax Biotech		RNA vaccine	Phase I (168) Jun 2020 – Dec 2021, China	Preclinical
HGC019 Gennova Biopharmaceuticals, HDT Biotech Corporation		RNA vaccine	Phase I (120) Jan 2021 – ?, India	Preclinical
Bangavax Globe Biotech Ltd of Bangladesh		RNA vaccine	Phase I (100) Randomized, Parallel Group Trial Feb 2021 – Feb 2022, Bangladesh	Preclinical
Unnamed Biological E. Limited, Baylor College of Medicine		Inactivated SARS‑CoV‑2 vaccine (using an antigen)	Phase I–II (360) Randomized, Parallel Group Trial Nov 2020 – Feb 2021, India	Preclinical
Nano Covax Nanogen Pharmaceutical Biotechnology JSC		Recombinant spike protein	Phase I (60) Dec 2020 – Jan 2021, Vietnam	Preclinical Tested on mice, hamsters, and monkeys. Approved for human clinical trials by the Vietnam Ministry of Health.
PTX-COVID19-B Providence Therapeutics		RNA vaccine	Phase I (60) Jan 2021 – May 2021, Canada	Preclinical
SARS-CoV-2 Sclamp/V451 UQ, Syneos Health, CEPI, Seqirus		Subunit vaccine (molecular clamp stabilized spike protein with MF59)	Terminated (120) Randomised, double-blind, placebo-controlled, dose-ranging. False positive HIV test found among participants. Jul–Oct 2020, Brisbane
V590 and V591/MV-SARS-CoV-2 Merck & Co. (Themis BIOscience), Institut Pasteur, University of Pittsburgh’s Center for Vaccine Research (CVR), CEPI			Terminated In phase I, immune responses were inferior to those seen following natural infection and those reported for other SARS-CoV-2/COVID-19 vaccines.

Efficacy

Cumulative incidence curves for symptomatic COVID‑19 infections after the first dose of the Pfizer–BioNTech vaccine (tozinameran) or placebo in a double-blind clinical trial. (red: placebo; blue: tozinameran)

The effectiveness of a new vaccine is defined by its efficacy. In the case of COVID‑19, a vaccine efficacy of 67% may be enough to slow the pandemic, but this assumes that the vaccine confers sterilizing immunity, which is necessary to prevent transmission. Vaccine efficacy reflects disease prevention, a poor indicator of transmissibility of SARS‑CoV‑2 since asymptomatic people can be highly infectious. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) set a cutoff of 50% as the efficacy required to approve a COVID‑19 vaccine. As of 7 January, authorized and approved vaccines have shown efficacies ranging from 62–90% for the Oxford–AstraZeneca vaccine (various dosage regimens) to 95% for the Pfizer-BioNTech COVID‑19 vaccine. BBV152 has not published efficacy results as of 7 January. With BBIBP-CorV, Sinopharm announced a vaccine's efficacy was 79%, which was lower than the 86% announced by the United Arab Emirates (UAE) on 9 December. The UAE based its results on an interim analysis of Phase III trials conducted from July. With CoronaVac, after three delays in releasing results, Instituto Butantan announced in January 2021 that the vaccine was 78% effective in mild cases and 100% effective against severe and moderate infections based on 220 COVID‑19 cases from 13,000 volunteers. Butantan declined to elaborate how the efficacy rate was calculated. The efficacy of the Moderna COVID-19 Vaccine is 96% for those aged 18 to 64. The Novavax vaccine was found to be 89% effective in the UK.

At the University of Oxford, researchers have as of early February 2021 begun enrolling volunteers in an 820 person trial to evaluate the efficacy of combining two different vaccines, a mix and match approach, as opposed to using two doses of the same vaccine. The ultimate goal of the study will be find whether the mix and match method is just as or more effective than the currently used practice. The study will utilize the shot developed by Pfizer and BioNTech with the University of Oxford and AstraZeneca shot, two vaccines which rely on different methods to deliver information to the cells of the recipient. Ugur Sahin has voiced his opposition to the trial in December, stating that a study "“will use up doses that people who need them could profit from, I am not happy about this,” though Pfizer and AstraZeneca have supported the trals.

SARS-CoV-2 variants

Main article: Variants of SARS-CoV-2

See also: 501.V2 variant § Vaccine evasion

In mid-December 2020, a new SARS‑CoV‑2 variant (VOC-202012/01) was identified in the UK. While preliminary data indicates that this variant showed an estimated increase in reproductive number (R) by 0.4 or greater and increased transmissibility of up to 70%, there is as yet no evidence for lower vaccine effectiveness.

A South African variant (501.V2) has also emerged, which is believed to be more contagious.

Early results suggest that both the Pfizer and Moderna vaccines protect against the UK variant. However they are less effective against the South Africa variant, with Moderna reporting that the current vaccine produced only one-sixth of the antibodies in response to the South African variant compared with the original virus. They have launched a trial of a new vaccine to tackle the South African variant.

On 4 February 2021, researchers at the University of Oxford released a study detailing the efficacy of the AstraZeneca vaccine against the British variant of the virus, finding the vaccine to be 75% effective from a study of around 256 participants' blood samples. These findings are only preliminary and have yet to be peer reviewed by other scientists.

Formulation

As of September 2020, eleven of the vaccine candidates in clinical development use adjuvants to enhance immunogenicity. An immunological adjuvant is a substance formulated with a vaccine to elevate the immune response to an antigen, such as the COVID‑19 virus or influenza virus. Specifically, an adjuvant may be used in formulating a COVID‑19 vaccine candidate to boost its immunogenicity and efficacy to reduce or prevent COVID‑19 infection in vaccinated individuals. Adjuvants used in COVID‑19 vaccine formulation may be particularly effective for technologies using the inactivated COVID‑19 virus and recombinant protein-based or vector-based vaccines. Aluminum salts, known as "alum", were the first adjuvant used for licensed vaccines, and are the adjuvant of choice in some 80% of adjuvanted vaccines. The alum adjuvant initiates diverse molecular and cellular mechanisms to enhance immunogenicity, including release of proinflammatory cytokines.

Deployment

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Updated May 1, 2024.

COVID-19 vaccine distribution by country

	Location	Vaccinated	Percent
	World	5,630,429,510	70.60%
	China	1,310,292,000	91.89%
	India	1,027,438,529	72.50%
	European Union	338,071,460	75.10%
	United States	270,227,181	81.39%
	Indonesia	203,878,473	74.00%
	Brazil	189,643,431	88.08%
	Pakistan	165,567,890	70.21%
	Bangladesh	151,507,133	88.50%
	Japan	104,705,133	84.47%
	Mexico	97,179,493	76.22%
	Nigeria	92,261,510	42.22%
	Vietnam	90,272,853	91.94%
	Russia	89,081,596	61.56%
	Philippines	78,484,848	67.92%
	Iran	65,199,831	73.63%
	Germany	64,876,299	77.82%
	Turkey	57,941,051	67.89%
	Thailand	57,005,497	79.62%
	Egypt	56,907,319	51.27%
	France	54,677,678	80.63%
	United Kingdom	53,806,963	79.97%
	Italy	50,936,719	86.28%
	South Korea	44,784,499	86.43%
	Ethiopia	44,073,766	35.72%
	Colombia	43,012,174	82.92%
	Argentina	41,529,058	91.25%
	Spain	41,351,234	86.95%
	Myanmar	34,777,314	64.64%
	Canada	34,763,194	90.40%
	Tanzania	34,434,933	52.57%
	Peru	30,563,708	89.76%
	Malaysia	28,138,157	82.91%
	Nepal	27,883,196	91.28%
	Saudi Arabia	27,041,364	74.27%
	Morocco	25,020,168	66.80%
	South Africa	24,209,938	40.42%
	Poland	22,877,472	57.40%
	Mozambique	22,869,646	69.37%
	Australia	22,236,698	84.95%
	Venezuela	22,157,232	78.29%
	Taiwan	21,899,240	91.65%
	Uzbekistan	21,674,823	62.59%
	Uganda	19,488,104	41.25%
	Afghanistan	18,896,999	45.95%
	Chile	18,088,517	92.27%
	Sri Lanka	17,143,761	78.53%
	Angola	16,522,932	46.43%
	Ukraine	15,729,617	36.19%
	Democratic Republic of the Congo	15,388,889	15.54%
	Ecuador	15,333,873	85.18%
	Cambodia	15,315,251	91.34%
	Sudan	15,207,452	32.44%
	Kenya	14,494,372	26.83%
	Ivory Coast	13,568,372	48.18%
	Ghana	13,221,421	39.50%
	Netherlands	12,596,446	71.72%
	Zambia	11,637,730	58.14%
	Iraq	11,332,925	25.47%
	Kazakhstan	10,858,101	55.98%
	Cuba	10,805,570	96.37%
	Rwanda	10,572,981	76.75%
	United Arab Emirates	9,991,089	100.00%
	Portugal	9,791,341	95.33%
	Belgium	9,267,479	79.51%
	Somalia	8,972,167	50.99%
	Guatemala	8,933,623	50.07%
	Romania	8,187,976	41.65%
	Greece	7,937,916	76.44%
	Algeria	7,840,131	17.75%
	Sweden	7,775,726	73.71%
	Guinea	7,679,918	55.41%
	Dominican Republic	7,367,193	65.61%
	Bolivia	7,361,008	60.94%
	Tunisia	7,218,871	58.42%
	Czech Republic	6,982,249	66.54%
	Hong Kong	6,919,512	92.40%
	Austria	6,899,873	77.18%
	Israel	6,723,119	71.15%
	Honduras	6,596,213	63.23%
	Belarus	6,527,591	68.46%
	Zimbabwe	6,437,808	40.25%
	Hungary	6,420,813	64.42%
	Nicaragua	6,260,823	90.10%
	Chad	6,254,729	35.29%
	Niger	6,217,508	23.72%
	Switzerland	6,096,911	69.75%
	Burkina Faso	6,089,089	26.86%
	Laos	5,888,649	79.31%
	Azerbaijan	5,373,253	52.10%
	Malawi	5,343,858	26.19%
	Tajikistan	5,282,863	54.18%
	Sierra Leone	5,252,127	61.03%
	Singapore	5,160,551	91.55%
	Jordan	4,821,579	43.25%
	Denmark	4,752,101	80.79%
	El Salvador	4,652,597	73.69%
	Costa Rica	4,641,899	89.60%
	Finland	4,524,288	81.65%
	Mali	4,354,292	19.27%
	Norway	4,346,995	79.99%
	New Zealand	4,301,605	82.96%
	South Sudan	4,287,160	39.28%
	Republic of Ireland	4,111,392	81.85%
	Paraguay	3,993,938	58.90%
	Liberia	3,825,381	72.14%
	Cameroon	3,753,733	13.45%
	Benin	3,697,190	27.69%
	Panama	3,533,477	80.15%
	Kuwait	3,457,498	80.99%
	Serbia	3,354,075	48.81%
	Syria	3,295,630	14.90%
	Oman	3,257,365	71.18%
	Uruguay	3,010,451	87.95%
	Qatar	2,852,178	105.83%
	Slovakia	2,822,919	51.82%
	Lebanon	2,740,227	49.92%
	Madagascar	2,700,391	9.12%
	Senegal	2,684,696	15.50%
	Central African Republic	2,600,389	46.61%
	Croatia	2,323,025	57.64%
	Libya	2,316,327	34.00%
	Mongolia	2,272,965	68.27%
	Togo	2,255,579	25.49%
	Bulgaria	2,108,377	31.09%
	Mauritania	2,103,754	44.42%
	Palestine	2,012,767	38.34%
	Lithuania	1,958,270	71.21%
	Botswana	1,951,054	74.18%
	Kyrgyzstan	1,736,541	26.19%
	Georgia	1,654,504	44.03%
	Albania	1,348,396	47.44%
	Latvia	1,346,184	71.84%
	Slovenia	1,265,802	59.72%
	Bahrain	1,241,174	84.31%
	Mauritius	1,123,773	86.48%
	Armenia	1,122,040	40.35%
	Moldova	1,108,879	33.88%
	Yemen	1,050,112	3.12%
	Lesotho	1,014,073	43.98%
	Bosnia and Herzegovina	943,394	28.91%
	Gambia	934,799	34.55%
	Kosovo	906,858	50.89%
	Timor-Leste	886,838	66.12%
	Estonia	870,168	65.62%
	Jamaica	859,773	30.41%
	North Macedonia	854,570	40.82%
	Trinidad and Tobago	753,588	49.39%
	Guinea-Bissau	747,057	35.48%
	Fiji	712,025	76.58%
	Bhutan	699,116	89.35%
	Republic of the Congo	695,760	11.92%
	Macau	679,703	97.77%
	Cyprus	670,969	74.88%
	Namibia	629,767	24.53%
	Eswatini	526,050	43.78%
	Haiti	521,396	4.50%
	Guyana	495,285	61.24%
	Luxembourg	481,957	74.42%
	Malta	478,953	89.81%
	Brunei	451,149	100.48%
	Comoros	438,825	53.41%
	Djibouti	421,573	37.61%
	Maldives	399,308	76.23%
	Papua New Guinea	382,020	3.77%
	Cabo Verde	356,734	60.68%
	Solomon Islands	343,821	47.47%
	Gabon	311,040	13.02%
	Iceland	309,770	84.00%
	Northern Cyprus	301,673	78.80%
	Montenegro	292,783	46.63%
	Equatorial Guinea	270,109	16.53%
	Suriname	267,820	45.26%
	Belize	258,473	63.78%
	New Caledonia	192,375	66.35%
	Samoa	191,403	86.07%
	French Polynesia	190,908	62.33%
	Vanuatu	176,624	54.06%
	Bahamas	174,810	42.64%
	Barbados	163,846	58.17%
	Sao Tome and Principe	140,256	61.68%
	Curaçao	108,601	56.81%
	Kiribati	100,900	76.88%
	Aruba	90,546	85.05%
	Seychelles	88,520	82.62%
	Tonga	87,342	81.73%
	Jersey	84,365	76.14%
	Isle of Man	69,560	81.44%
	Antigua and Barbuda	64,290	68.97%
	Cayman Islands	62,023	90.25%
	Saint Lucia	60,140	33.43%
	Andorra	57,901	72.52%
	Guernsey	54,223	85.62%
	Bermuda	48,554	75.65%
	Grenada	44,241	35.26%
	Gibraltar	42,175	129.07%
	Faroe Islands	41,715	85.04%
	Greenland	41,243	72.52%
	Saint Vincent and the Grenadines	37,527	36.10%
	Burundi	36,909	0.29%
	Saint Kitts and Nevis	33,794	70.88%
	Dominica	32,995	45.57%
	Turks and Caicos Islands	32,815	71.76%
	Turkmenistan	32,240	0.53%
	Sint Maarten	29,788	67.41%
	Liechtenstein	26,771	68.02%
	Monaco	26,672	67.49%
	San Marino	26,357	77.50%
	British Virgin Islands	19,466	62.55%
	Caribbean Netherlands	19,109	72.26%
	Cook Islands	15,112	88.73%
	Nauru	13,106	103.27%
	Anguilla	10,854	68.36%
	Wallis and Futuna	7,150	61.66%
	Tuvalu	6,368	53.40%
	Saint Helena, Ascension and Tristan da Cunha	4,361	71.83%
	Falkland Islands	2,632	75.57%
	Tokelau	2,203	116.38%
	Montserrat	2,104	47.68%
	Niue	1,650	102.23%
	Pitcairn Islands	47	100.00%
	North Korea	0	0.00%

These paragraphs are an excerpt from Deployment of COVID-19 vaccines.[edit]

As of 3 January 2024, 13.53 billion COVID-19 vaccine doses have been administered worldwide, with 70.6 percent of the global population having received at least one dose. While 4.19 million vaccines were then being administered daily, only 22.3 percent of people in low-income countries had received at least a first vaccine by September 2022, according to official reports from national health agencies, which are collated by Our World in Data.

During a pandemic on the rapid timeline and scale of COVID-19 cases in 2020, international organizations like the World Health Organization (WHO) and Coalition for Epidemic Preparedness Innovations (CEPI), vaccine developers, governments, and industry evaluated the distribution of the eventual vaccine(s). Individual countries producing a vaccine may be persuaded to favor the highest bidder for manufacturing or provide first-class service to their own country. Experts emphasize that licensed vaccines should be available and affordable for people at the frontlines of healthcare and in most need.

In April 2020, it was reported that the UK agreed to work with 20 other countries and global organizations, including France, Germany, and Italy, to find a vaccine and share the results, and that UK citizens would not get preferential access to any new COVID‑19 vaccines developed by taxpayer-funded UK universities. Several companies planned to initially manufacture a vaccine at artificially low prices, then increase prices for profitability later if annual vaccinations are needed and as countries build stock for future needs.

The WHO had set out the target to vaccinate 40% of the population of all countries by the end of 2021 and 70% by mid-2022, but many countries missed the 40% target at the end of 2021.

Liability

On 4 February 2020, US Secretary of Health and Human Services Alex Azar published a notice of declaration under the Public Readiness and Emergency Preparedness Act for medical countermeasures against COVID‑19, covering "any vaccine, used to treat, diagnose, cure, prevent, or mitigate COVID‑19, or the transmission of SARS-CoV-2 or a virus mutating therefrom", and stating that the declaration precludes "liability claims alleging negligence by a manufacturer in creating a vaccine, or negligence by a health care provider in prescribing the wrong dose, absent willful misconduct". The declaration is effective in the United States through 1 October 2024.

In the European Union, the COVID‑19 vaccines are licensed under a Conditional Marketing Authorisation which does not exempt manufacturers from civil and administrative liability claims. While the purchasing contracts with vaccine manufacturers remain secret, they do not contain liability exemptions even for side-effects not known at the time of licensure.

Society and culture

Access

Nations pledged to buy doses of COVID-19 vaccine before the doses were available. Though high-income nations represent only 14% of the global population, as of 15 November 2020, they had contracted to buy 51% of all pre-sold doses. Some high-income nations bought more doses than would be necessary to vaccinate their entire populations.

On 18 January 2021, WHO Director-General Tedros Adhanom Ghebreyesus warned of problems with equitable distribution: "More than 39 million doses of vaccine have now been administered in at least 49 higher-income countries. Just 25 doses have been given in one lowest-income country. Not 25 million; not 25 thousand; just 25."

The Chinese Sinopharm's COVID-19 vaccine was authorized for emergency use by Bahrain and the United Arab Emirates in December 2020. The vaccine was widely being used in the UAE, despite pending approval from the World Health Organization. In February 2021, a report revealed that the UAE was running a pay-to-access vaccination programme to “bring tourism into the area”. The Arab country was offering access to BBIBP-CorV only to a few elite foreign tourists, making it a selling point of tourism despite a global scarcity of doses.

Misinformation

Main article: Misinformation related to the COVID-19 pandemic § Vaccine misinformation

Vaccine hesitancy

Some 10% of the public perceives vaccines as unsafe or unnecessary, refusing vaccination – a global health threat called vaccine hesitancy – which increases the risk of further viral spread that could lead to COVID‑19 outbreaks. In mid-2020, estimates from two surveys were that 67% or 80% of people in the U.S. would accept a new vaccination against COVID‑19, with wide disparity by education level, employment status, race, and geography.

A poll conducted by National Geographic and Morning Consult demonstrated a gender gap on willingness to take a COVID‑19 vaccine in the U.S., with 69% of men polled saying they would take the vaccine, compared to only 51% of women. The poll also showed a positive correlation between education level and willingness to take the vaccine.

In an effort to demonstrate the vaccine's safety, prominent politicians have received it on camera, with others pledging to do so.

See also

• 2009 swine flu pandemic vaccine
• COVID‑19 drug development
• COVID‑19 drug repurposing research

Further reading

• Funk CD, Laferrière C, Ardakani A (2020). "A Snapshot of the Global Race for Vaccines Targeting SARS-CoV-2 and the COVID-19 Pandemic". Front Pharmacol. 11: 937. doi:10.3389/fphar.2020.00937. PMC 7317023. PMID 32636754.
• Development and Licensure of Vaccines to Prevent COVID-19: Guidance for Industry (Report). U.S. Food and Drug Administration. June 2020. {{cite report}}: Cite has empty unknown parameter: |lay-url= (help)
• Ramsay M, ed. (2020). "Chapter 14a: COVID-19". Immunisation against infectious disease. Public Health England.
• Levine, Hallie (23 September 2020). "The 5 Stages of COVID-19 Vaccine Development: What You Need to Know About How a Clinical Trial Works". Johnson & Johnson.
• Haelle, Tara (12 December 2020). "Every Covid-19 Vaccine Question You'll Ever Have, Answered". Medium.
• Zimmer C, Sheikh K, Weiland N (20 May 2020). "A New Entry in the Race for a Coronavirus Vaccine: Hope". The New York Times.

Vaccine protocols

• "Protocol mRNA-1273-P301" (PDF). Moderna.
• "Protocol C4591001 PF-07302048 (BNT162 RNA-Based COVID-19 Vaccines)" (PDF). Pfizer.
• "Protocol AZD1222 – D8110C00001" (PDF). AstraZeneca.
• "Protocol VAC31518COV3001; Phase 3" (PDF). Janssen Vaccines & Prevention.

External links

• COVID‑19 Vaccine Tracker. Regulatory Focus
• "STAT's Covid-19 Drugs and Vaccines Tracker". Stat.
• "COVID-19 vaccines: development, evaluation, approval and monitoring". European Medicines Agency.
• "Vaccine Development – 101". U.S. Food and Drug Administration.
• "Coronavirus Variants and Mutations". The New York Times.
• M.I.T. Lecture 10: Kizzmekia Corbett, “Vaccines” on YouTube