Ebola is likely to disrupt "critical commercial and transport" activities in affected countries for at least a month, and could hurt government budgeting and economic growth.
The new assessment of Africa's worst-ever outbreak of Ebola comes from the rating agency Moody's. The report says efforts to stop the spread of the deadly virus have prompted officials to close borders, markets, and schools; put non-essential workers on leave and cancel sporting events. The deadly virus has also forced some hospitals to close after Ebola sickened or killed medical staff in Liberia, Guinea and Sierra Leone.
Ebola worries also mean several local and international airlines have cancelled flights to those countries, and some oil companies are moving staff out of the area. The major mining company ArcelorMittal is stopping development of some iron ore operations in Liberia.
The Moody's report says if the small number of Ebola cases in Nigeria become a "significant" outbreak, it could have a "considerable" impact on the nation's vital oil and natural gas operations. Nigeria is Africa's largest economy, and a major oil exporter.
Ebola has killed at least 1,000 people and sickened even more. Experts say it is too early to calculate the cost of the disruptions.