Vaccines typically require years of research and testing before they reach the clinic. However, scientists and regulators have been working extremely hard, and several vaccines against Sars-CoV-2, the virus that triggers COVID-19, are already in use. In the meantime, we are no longer anxious about whether and when there will be a vaccine, but when we will be vaccinated, which vaccine we will get, and whether the vaccination will also protect against mutations.

The work began in January 2020 with the decoding of the SARS-CoV-2 genome. In March 2020, the first human safety studies of a vaccine began. BioNTech/Pfizer’s vaccine was the first to receive approval: first from the UK Medicines Regulatory Agency in December 2020, followed by emergency approvals in the US and the EU. It was the first time an mRNA vaccine received approval and is produced on a large scale

Currently, four vaccines have been approved for application in the EU, and partial registration dossiers have already been submitted for others. So far, all approved vaccines show very good efficacy. We look here at a few of the differences between the EU-approved vaccines.

 

Vaccine Types

 

 

Storage, Administration, and Efficiency Results from Phase 3 Trials

Vaccine efficacy is generally reported as a relative risk reduction. Relative risk is the ratio of attack rates with and without a vaccine. This means, an individual is less likely to get sick from any contact with COVID-19 than an individual without vaccination by the percentage given above.

However, the vaccine efficacy should be viewed in light of the risk of becoming infected with and contracting COVID-19. This varies between populations and over time. The percentages given above depend on the conditions in the phase III test population, including infection incidence and mutations present during testing. They were different for the four vaccines.

Important to know is that all these vaccines have shown 100% efficacy rates against death and hospitalization.

 

Effectiveness of the Vaccines Against the Coronavirus Variants

 

References

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Also of Interest

• Searching for a Vaccine
  Picture describes what happens during vaccination and gives a snapshot of which Covid-19 vaccine candidates are in which clinical phases
  https://doi.org/10.1002/chemv.202000075
• Interview: Interview with Ingmar Hoerr, Pioneer of mRNA Technology
  As a Ph.D. student, Hoerr discovered that mRNA can be used as a therapeutic vaccine or agent when administered directly into tissues
  https://doi.org/10.1002/chemv.202100030
• ChemistryViews Collection: SARS-CoV-2 Virus – What We Know About Vaccines and Immunity