Omicron will likely 'dominate and overwhelm' the world in 3-6 months, doctor says today. "Frankly, omicron will dominate and overwhelm the whole world in three to six months," Singapore doctor Leong Hoe Nam told CNBC's "Street Signs Asia. New vaccines targeting omicron are a "nice idea" but won't be practical because of the transmissibility of the strain, he said.

Moderna CEO Stephane Bancel on Monday said it will take months to develop and ship a vaccine that specifically targets the omicron variant.

Pfizer CEO Albert Bourla also said shots could be ready in less than 100 days, or slightly over three months.

Leong agreed that a three-dose vaccine regimen would likely protect against severe disease, but pointed out that many countries still have low vaccination rates.