South Korea has reported its first cases of the omicron variant of the coronavirus amid a spike in COVID-19 cases. 

According to health authorities, the first cases were confirmed in five people on Wednesday, including a couple and their friend in their 40s.

The couple visited Nigeria from November 14 through 23 and returned on November 24 and tested positive for COVID-19 the next day. 

As both were fully vaccinated, they were reportedly exempted from mandatory quarantine after returning from the trip.
 
The couple's teenage son also tested positive to COVID-19, his omicron test results are pending. 

Two more omicron cases were confirmed in two women in their 50s, who also returned from a trip to Nigeria. They returned on November 23, one day before the couple. 

The number of the new variant may rise further as there are four suspected cases.