The German company BioNTech and its partner company Pfizer have announced preliminary results suggesting that their coronavirus vaccine is more than 90 percent effective. 

The news has prompted a widespread raising of spirits, but it has also thrown up a lot of questions: What is the vaccine? How does it work? When can we expect it? And who will be vaccinated first? Here's what we know so far. 

What have Pfizer and BioNTech announced?

Pfizer and BioNTech carried out a late-stage clinical trial of their coronavirus vaccine in July, involving nearly 44.000 people. Of those, half received the vaccine, while the other half were given a placebo of salt water. The companies then waited for trial participants to get sick, to see if the vaccine offered any protection. 

So far, just 94 participants have contracted COVID-19; fewer than nine of them had received the vaccine. This suggests that the vaccine is over 90 percent effective. Pfizer and BioNTech have reported no serious safety concerns. 

That’s a good result - way above the 50 percent threshold set by the USA’s Food and Drug Administration for vaccine makers who want to submit their products for emergency authorisation. Influenza vaccines, for comparison, are somewhere between 40 to 60 percent effective at best, because the flu virus keeps evolving year after year. 

“The first results are a glimmer of hope on an otherwise gloomy horizon,” said Professor Dr Clemens Wendtner from Munich Clinic Schwabing. He added that the manufacturing process can be adapted relatively quickly to virus mutations.  

How does the COVID-19 vaccine work?

Vaccines usually involve patients being given a shot of a weakened or dead part of a virus or bacteria, to prompt an immune response from the body. This means that, when the body encounters the real disease-causing bug, it already has the “tools” it needs to attack it. 

The new mRNA (“Messenger RNA”) vaccine also works by training the immune system to recognise a threat and then produce antibodies to protect itself. However, instead of containing weakened parts of the virus, the mRNA vaccine makes the body produce those proteins itself, using a “messenger” molecule that contains genetic instructions. On their own, these viral proteins are not harmful, but they do trigger a defensive response from the immune system. 

Which countries will get the new vaccine first?

The chief executive of Pfizer has said that the company could have 30 to 40 million doses of the vaccine ready before the end of 2020, which is enough for 15 to 20 million people to have an initial shot and a booster three weeks later. A further 1,3 billion doses should be ready in 2021. The vaccine seems to begin working within four weeks. 

The US has already closed a 1,64-billion-euro contract with the two biochemical companies, securing 100 million doses of the vaccine. A similar agreement, for 200 million doses, exists between Pfizer and BioNTech and the European Union. Japan has also earmarked 120 million doses, and the UK a further 30 million - meaning that, initially, supply will fall far short. 

Who will be vaccinated first in Germany?

Together with the federal states, the German government is already making plans for a nationwide vaccination strategy, which will see a total of 60 centres established across the country. Merkel has already promised that first access to any approved vaccine will be reserved for health workers and risk groups - which includes older people and those with underlying health conditions. 

Federal Health Minister Jens Spahn has laid out a stepped vaccination strategy that divides the population into three groups: 

• Group 1: Very old people and risk groups (e.g. people with previous lung diseases, overweight people and asthmatics)
• Group 2: Healthcare workers and key workers (including doctors, nurses, health authorities, police, fire brigade, teachers and educators)
• Group 3: The rest of the population (younger people without underlying health conditions)

“In the first weeks and months there will not be enough vaccines for everybody who wants to be vaccinated,” Spahn said. “That’s why we have to prioritise.” According to Bild, the federal government expects the first vaccinations in Germany to take place in the first quarter of 2021, at the earliest. 

Do I have to get vaccinated against COVID-19?

No. Politicians in Germany have been categorical about this: “Nobody will be forced to be vaccinated; it is a voluntary decision,” Merkel stressed at a press conference earlier this month. 

Her words were echoed by Jens Spahn: “Vaccinations will be voluntary,” he said, although he emphasised how important it is that as many people as possible are vaccinated, to ensure the best possible protection for the entire population. 

How many people have to get vaccinated to ensure herd immunity?

Professor Dr Gerald Haug, the President of the German Academy of Sciences Leopoldina, says we can “look forward to summer 2021 with a lot of optimism. If everyone pulls together, we will take decisive steps by the summer to leave the pandemic behind us.” 

In his estimation, around 70 percent of the population would need to get vaccinated in order for the drive to be highly effective. Other experts have put forward a slightly lower figure of somewhere between 55 and 65 percent. 

In Germany, this would mean that around 55 million people would have to be vaccinated against coronavirus before herd immunity could be achieved.