The first case of the Omicron variant of coronavirus was reported in California, United States, at the beginning of this month. The appearance of the new variant prompted the Biden administration officials to renew the urgent calls for citizens to get fully vaccinated.

The first patient is supposedly a traveler who returned to California from South Africa on Nov. 22. While he was in isolation, the Centers for Disease Control and Prevention stated that the individual was fully vaccinated and presented mild symptoms that improved in time.

Close contacts of the individual were tested negative, as the agency declared. The WHO warned everybody that the new variant presents a higher risk. The variant had first appeared in southern Africa, and it had spread to more than 20 countries so far.