Vaccine Overview
Vaccination can be the most efficient and effective measures in controlling the pandemics and save millions of lives. There are currently more than 60 COVID-19 vaccine candidates in clinical development and over 170 in pre-clinical development. The GVN is providing valuable information and resources for COVID-19 vaccines.
Spike Protein of SARS-CoV-2 for Vaccine Development
- Spike (S) protein plays the most important roles in viral attachment, fusion, and entry.
- Receptor binding domain (RBD) of the S protein binds to human ACE2 receptor.
- RBD is a target for induction of neutralizing antibodies.
- For current COVID-19 vaccine development, the spike protein is expressed by using various platforms to induce immune responses.
Available COVID-19 Vaccines
| Company | Type of Vaccine | In Use |
|---|---|---|
| Pfizer-BioNTech | mRNA Based | EU, Argentina, Mexico, Saudi Arabia, Canada, Bahrain, US, UK |
| Moderna | mRNA Based | Canada, Israel, Switzerland, EU, US, UK |
| Oxford-AstraZeneca | Adenovirus vectored | Algeria, Argentina, Bangladesh, Bhutan, Brazil, Chile, Dominican Republic, Egypt, El Salvador, EU, Iceland, India, Iraq, Kuwait, Maldives, Mexico, Mongolia, Morocco, Nepal, Norway, Pakistan, Philippines, Seychelles, Sri Lanka, South Africa, South Korea, Thailand, UK |
| Johnson and Johnson | Adenovirus vectored | South Africa, US, UK, EU, Canada |
| Gamaleya (Sputnik V) | Two different adenoviruses | Algeria, Argentina, Bolivia, Hungary, Palestine, Paraguay, Serbia, Turkmenistan, UAE, and Venezuela, Belarus, Russia. |
| CanSino Biologics (Petrovax) | Adenovirus vectored | China’s Central Military Commission (military use) |
| Sinopharm | Inactivated | Bahrain, China, Pakistan, UAE |
| Sinovac | Inactivated | Brazil, China, Indonesia |
| Research Institute for Biological Safety Problems | Inactivated | Kazakhstan |
| Bharat Biotech | Inactivated | India |
| Type of Vaccine | How It Works |
|---|---|
| Messenger RNA based vaccines | Directly deliver the genetic information to the cell for expressing the spike protein into the body. The expressed viral protein will induce immune responses. |
| Viral vectored vaccines | Deliver and express the spike protein using other viruses (vector). These viral vectors are safe to be used as a vaccine (example: adenovirus). |
| Nanoparticle based vaccines | Direct injection of the spike protein assembled into nanoparticles. The protein will be presented to the immune cells to induce the immune responses |
| DNA based vaccines | Deliver a plasmid encoding the spike protein into the cells. The protein will be presented to the immune cells to induce the immune responses |
| Inactivated vaccines | Classic vaccine approach. Use of killed virus particles containing the spike protein but also all other viral proteins |
| Live-attenuated vaccines | Use of a living but weakened version of a virus (example: measles virus). Mimic a natural infection |
Sources for Vaccine Safety and Other Information
- CDC Guidelines: When You’ve Been Fully Vaccinated
- WHO Vaccines and immunization: Vaccine safety
- CDC Vaccines & Immunizations
- CDC Myths and Facts about COVID-19 Vaccines
- NIH Vaccines
- European Medicine Agency COVID-19 Vaccines
- Tracking COVID-19 vaccine distribution and administration activities:
Center for Disease Control and Prevention, USA
Johns Hopkins University