The imported cases were detected from samples collected between November 21-25 from travellers returning to Ghana from three countries, Noguchi said in a Tweet on December 1, 2021.
"The Omicron variant was detected in 28% (34 out of 120) of returning traveller samples (collected from 21-25 November) sequenced," the tweet said.
The Institute also encouraged the public to continue adhering to the COVID-19 prevention protocols.
"These are the first imported cases of the variant into Ghana, and we are closely monitoring its potential spread in the local population. We encourage the general public to continue adhering to the COVID-19 prevention protocols".
The update from Noguchi came hours after the Ghana Health Service reported the country's first cases of the new variant.
The Director-General of the Ghana Health Service, Dr. Patrick Kuma-Aboagye who announced this Wednesday in Accra said the first case was discovered on Sunday, November 21, 2021, in a Nigerian traveller through sequencing. Another case was recorded in a traveller from South Africa.
The World Health Organization (WHO) has warned that Omicron poses a "high infection risk".