Nigeria has banned entry of travelers from 13 countries, including the U.S., the U.K., China, Italy, and France, as part of efforts to avert a coronavirus outbreak in the country, local media reported on Wednesday.

The ban will be enforced starting Friday and will last for at least four weeks, according to a report by local news website Pulse.

The Nigerian government has also advised citizens to avoid traveling to those 13 countries — the U.S., the U.K., China, Italy, Iran, South Korea, Spain, Japan, France, Germany, Norway, Switzerland, and the Netherlands.

As of Wednesday, Nigeria had only three confirmed COVID-19 cases,

Read more: COVID-19: Nigeria bans travelers from 13 countries