Ghana will enforce tightened COVID-19 restrictions for international travelers to avert a fourth wave of the pandemic, authorities said.

Beginning from Sunday, Dec. 12, all persons above 18 years arriving in Ghana would be required to provide evidence of full vaccination against COVID-19, the Ghana Health Service (GHS) said in a statement issued late Thursday.

"All unvaccinated Ghanaians and residents of Ghana currently outside the country and intend to return within 14 days from the midnight of Dec. 12, 2021, are exempted. However, they will be vaccinated on arrival," the GHS said.

The decision was made as confirmed COVID-19 cases arriving at Kotoka International Airport (KIA) surged over 40 percent year-on-year in November, the statement said.

"We have since been recording an average of 20 positive cases a day at KIA, and there is a significant difference in the percentage of these infections based on vaccination status recorded at KIA," the GHS said.

"Available data from KIA show that a positive COVID-19 person is three times more likely to be unvaccinated," the statement said.

The GHS observed that globally, many countries are experiencing their fourth wave of COVID-19, "and many travelers from those countries come to Ghana."

"This is likely to increase during the festive season," it said.

Ghana has so far detected 34 cases of the Omicron variant among international arrivals, the GHS said.

The west African country commenced mandatory vaccination for designated groups of people earlier this month.