Rwanda has banned anyone who has been exposed to Marburg virus from leaving the country as it seeks to stop the outbreak spreading beyond its borders.

Amid an outbreak of Marburg virus in Rwanda, travelers coming into the United States who have been in Rwanda in the previous 21 days will be screened starting next week, the US Department of Health and Human Services announced Monday.

Rwanda’s health minister says authorities are tracing every potential contact of the index case in the country’s outbreak of Marburg virus disease to reduce the risk of wider spread