Omicron COVID variant 'certainly' not more severe than Delta: Top US scientist

Anthony Fauci, the chief medical adviser to US President Joe Biden, has that he was encouraged by early reports on the severity of the new omicron variant, but warned against drawing premature conclusions.

"Thus far, it does not look like there's a great degree of severity to [the omicron variant],'' Fauci told CNN.

"But we have really got to be careful before we make any determinations that it is less severe or it really doesn't cause any severe illness, comparable to delta," he added.

The medical expert's comments followed reports that hospitalization rates have not appeared to rise in any worrying way in South Africa, which first detected the highly contagious variant.

Fauci went on to say that he was hopeful that the travel ban against several African countries could be lifted "in a quite reasonable period of time."

Omicron has been detected in dozens of US states already, but the delta variant remains by far the dominant strain, fueling a surge in cases and hospitalizations.

Experts have warned that even if the omicron variant proves to be milder in its effects, the highly contagious virus will keep giving some of the people it infects serious problems.

Health authorities around the world continue to recommend vaccines and booster shots against COVID-19.