"There Are 4,000 Variants Of Virus That Causes COVID-19": UK Minister Nadhim Zahawi (FILE) London: There are around 4,000 variants of the virus that causes COVID-19 around the world now so all vaccine manufacturers including Pfizer Inc and AstraZeneca Plc are trying to improve their vaccines, a British minister said. Thousands of variants of the type of coronavirus that causes COVID-19 have been documented as the virus mutates, including the so-called British, South African and Brazilian variants which appear to spread more swiftly than others. "Its very unlikely that the current vaccine won't be effective on the variants whether in Kent or other variants especially when it comes to severe illness and hospitalisation," Vaccine Deployment Minister Nadhim Zahawi told Sky News.