EUROPE CAN ACHIEVE herd immunity against coronavirus within the next four months, according to the head of German pharmaceutical company BioNTech.

The company developed the first widely approved Covid-19 vaccine with US partner Pfizer.

While the exact threshold required to reach that critical level of immunisation remains a matter of debate, experts say a level above 70% would significantly disrupt the transmission of coronavirus within a population.

“Europe will reach herd immunity in July, latest by August,” said Ugur Sahin, BioNTech’s chief executive.

His company’s Covid-19 vaccine makes up a large share of the doses administered in Europe and North America, where it is more commonly known as the Pfizer shot.

Mr Sahin said data from people who have received the vaccine show that the immune response gets weaker over time, and a third shot will probably be required.

Studies show the efficacy of the BioNTech/Pfizer vaccine declines from 95% to about 91% after six months, he said.

“Accordingly, we need a third shot to get the vaccine protection back up to almost 100% again” Mr Sahin said.

He suggested this should be administered nine to 12 months after the first shot.

“And then I expect it will probably be necessary to get another booster every year or perhaps every 18 months again,” he said.

Concerns have been raised that existing vaccines might be less effective against new variants of the virus now emerging in different parts of the world.

Mr Sahin said BioNTech has tested its vaccine against more than 30 variants, including the now-dominant one first detected in Britain, and found the shot triggers a good immune response against almost all of them in the lab. In cases where the immune response was weaker, it remained sufficient, he said, without providing exact figures.