• Not all vaccines work the same way.
  • This is how some of the COVID-19 vaccines work - and how they differ.
  • Several vaccines are being used to tackle the pandemic worldwide.

The approval of the first COVID-19 vaccines has renewed hope across the world that the battle against the pandemic that has so far killed more than 1.6 million people may eventually be won.

No single vaccine is likely to be distributed globally; instead a range of treatments will be used. Here are two of the different vaccines and how they work.

The Pfizer-BioNTech vaccine

How do RNA vaccines work?
This is how RNA vaccines - like the Pfizer/BioNTech one - work.
Image: Wellcome Trust

This RNA vaccine – one of the world's first to be approved – was developed by US pharmaceutical giant Pfizer and its German partner BioNTech. Its active ingredient is messenger RNA, which is closely related to DNA and contains a synthetic version of COVID-19’s genetic code.

Once injected, the patient’s immune cells follow the vaccine’s instructions to build the coronavirus ‘spike’ protein. Their body then launches an attack against it, thereby learning how to defeat the real virus. The vaccine, which requires two doses, has 95% efficacy rate. However, a significant drawback is that it needs to be stored at -70C.

The Pfizer-BioNTech vaccine received authorization for use by the UK regulator on 2 December. It has also been approved in other countries, including the US, Canada and in the European Union. US company Moderna has also developed an RNA vaccine, which has also been approved for use in the United States.

The Oxford-AstraZeneca vaccine

Hhow viral vectors vaccines, like the Pfizer-BioNTech COVID-19 vaccine, work
This is how the Pfizer-BioNTech vaccine works.
Image: Wellcome Trust

This viral vector vaccine was developed by the University of Oxford and AstraZeneca and works by altering a harmless adenovirus so it contains the genetic code for the coronavirus spike protein.

Vaccines, Health and healthcare, Gavi

What is the World Economic Forum doing about access to vaccines?

In 2000, Gavi, the Vaccine Alliance was launched at the World Economic Forum's Annual Meeting in Davos, with an initial pledge of $750 million from the Bill and Melinda Gates Foundation.

The aim of Gavi is to make vaccines more accessible and affordable for all - wherever people live in the world.

Along with saving an estimated 10 million lives worldwide in less than 20 years,through the vaccination of nearly 700 million children, - Gavi has most recently ensured a life-saving vaccine for Ebola.

At Davos 2016, we announced Gavi's partnership with Merck to make the life-saving Ebola vaccine a reality.

The Ebola vaccine is the result of years of energy and commitment from Merck; the generosity of Canada’s federal government; leadership by WHO; strong support to test the vaccine from both NGOs such as MSF and the countries affected by the West Africa outbreak; and the rapid response and dedication of the DRC Minister of Health. Without these efforts, it is unlikely this vaccine would be available for several years, if at all.

Read more about the Vaccine Alliance, and how you can contribute to the improvement of access to vaccines globally - in our Impact Story.

The adenovirus is then injected into the body, where it transports the genetic instructions into the patient’s cells. These then start to produce the protein, triggering an immune response and priming the body to attack the real virus later.

The Oxford-AstraZeneca vaccine – which also requires two doses – has been approved for use in the United Kingdom. Research suggests that it could be up to 90% effective. It is both cheaper than its rivals and easier to store, meaning it could play a vital role in fighting the pandemic worldwide.