The world is facing about 4000 strains of Coronavirus including the British, South African and Brazilian

Britain said on Thursday, that the world is facing about 4000 strains of the virus that causes Covid-19 disease, which has led to a race to improve vaccines, as researchers began testing the combination of two doses, one of the Pfizer vaccine and the other of the AstraZeneca vaccine.

Thousands of strains have been documented as the virus mutates, including the so-called British, South African and Brazilian strains, which appear to spread faster than others.

“It is highly unlikely that the current vaccine will not be effective with mutated strains, whether in Kent County or with other strains, especially when it comes to severe symptoms and hospitalization,” Nazem al Zahawi, the British minister responsible for developing vaccines, told Sky News.

“All the manufacturers, Pfizer-Biontec, Moderna, Oxford-AstraZeneca and others are looking at how to improve their vaccines to make sure we are ready for any strain.. there are about 4,000 different types of Covid around the world now,” he added.

With the emergence of thousands of strains resulting from the mutation of the virus with its cloning, it is likely that a very small minority of them only has significance and that the virus changes in a noticeable way, according to the British Medical Journal.

“We have the largest genome sequencing industry – we have about 50 percent of the genome sequencing industry in the world – and we maintain a library of all strains to be prepared to deal, whether in the fall or later, with whatever challenge the virus may present and produce the next vaccine,” al Zahawi said.

The Coronavirus has killed 2,284,417 people globally since it appeared in China in late 2019, according to Johns Hopkins University of Medicine.

Israel is far ahead of the rest of the world in terms of the ratio of vaccinations to the population, followed by the UAE, the United Kingdom, Bahrain, the United States, Spain, Italy and Germany.

On Thursday, Britain launched a trial to assess immune responses upon vaccination with two doses, one from Pfizer and the other from AstraZeneca.

The British researchers based on the experiment said that the data on vaccinating people with two different types of vaccines may help understand whether doses can be distributed more flexibly in the world. 

Preliminary data on immune responses is expected around June.

The trial will test the immune responses to vaccination first with a dose of the Pfizer vaccine, followed by a booster dose of the AstraZeneca vaccine, and vice versa, with intervals between the two doses spanning four weeks and 12 weeks.