The strain, known as B.1.1.7, was identified in Britain late last year and has become the most common strain in the United States, according to the United States Centers for Disease Control and Prevention.

The study in the medical journal analyzed a group of 496 Covid-19 patients who were admitted to British hospitals in November and December last year, comparing outcomes in patients infected with B.1.1.7 or other variants. The researchers found no difference in risks of severe disease, death, or other clinical outcomes in patients with B.1.1.7 and other variants.

"Our data, within the context and limitations of a real-world study, provide initial reassurance that severity in hospitalized patients with B.1.1.7 is not markedly different from severity in those without," the researchers said in the study.

A separate study published in The Lancet Public Health medical journal found that vaccines were likely to be effective against the British variant since there was no apparent increase in reinfection rate when compared to non-U.K. variants.

According to British scientists, the British variant was about 40-70 percent more transmissible than previously dominant variants.

The studies also confirmed the previous findings that B.1.1.7 was more transmissible.