A preliminary analysis shows. that the corornavirus vaccine can prevent 90% of people from getting Covid-19. 43,500 people have been put under testing in six countries and no safety concerns have been raised so far.

The companies, Pfizer and BioNTech plan to apply for emergency approval for the usage of vaccine by the end of the November. They describe the development as a “great day for science and humanity”.

Previous trials have shown the vaccine trains the body to make both antibodies – and another part of the immune system called T-cells to fight the coronavirus.

Two doses, three weeks apart, are needed. The trials – in US, Germany, Brazil, Argentina, South Africa and Turkey – show 90% protection is achieved seven days after the second dose.

Pfizer believes it will be able to supply 50 million doses by the end of this year, and around 1.3 billion by the end of 2021. The UK should get 10 million doses by the end of the year, with a further 30 million doses already ordered. However there are logistical challenges, as the vaccine has to be kept in ultra-cold storage at below minus 80C.