DAKAR, Senegal -- The U.N. is warning that food prices are rising in countries hit by Ebola and that it'll get worse because many farmers won't be able to access fields during the upcoming harvests of rice and corn.

An Ebola outbreak in West Africa has killed more than 1,500 people, and authorities have cordoned off entire towns in an effort to prevent the virus' spread. Many airlines have suspended flights to and from the affected countries, and seaports are seeing less traffic.

The U.N. Food and Agriculture Organization said Tuesday that those measures drove up food prices as much as 150 per cent in one market.

The U.N. has said 1.3 million people in Liberia, Guinea and Sierra Leone will need help feeding themselves in coming months.