Torrential downpours and flash floods have affected more than a million people across the African continent, displacing hundreds of thousands, killing at least 150 and submerging whole towns and villages in some places. On Saturday, the U.N. warned more rains and an outbreak of disease may be on the way.

"The rains are set to continue and we are really concerned about the situation, because a lot of people are homeless and infectious diseases could emerge," said Elisabeth Byrs of the U.N.'s Office for the Coordination of Humanitarian Affairs.

So far, nine people are reported to have died and 150,000 have been made homeless in eastern Uganda since August. Another 400,000, mainly subsistence farmers, have lost their livelihoods after their fields were flooded or roads washed away and the rains are forecast to worsen in the next month.

"The problem is getting worse by the hour. Access to some communities is almost impossible. We will need boats and helicopters to deliver emergency interventions," said Minister for Relief and Disaster Preparedness Musa Ecweru, who spent Saturday viewing the affected areas by plane.

Uganda's neighbors are also affected. Hundreds of thousands need aid in Kenya and Ethiopia, which was devastated by flooding last year as well.

In Sudan, refugees who had just returned at the end of a brutal civil war had to flee their homes through waist-high waters. The government said they are "the worst floods in living memory," 119 people have died and tens of thousands are homeless. The death toll may rise as much of its vast swampland is inaccessible except by air.

The problem stretches across the continent, to at least 17 countries, said Byrs. People need clean water after their normal sources were contaminated, and emergency food and shelter after fields and houses were washed away.

But some of the damage will take longer to repair. In the tiny west African nation of Togo, 20 people are dead and 66,000 displaced after a deluge washed away 100 bridges and 7 dams in the last week. The waters also destroyed 46 schools and some college buildings, forcing authorities to postpone the start of the school year.

French military helicopters from the peacekeeping mission in nearby Ivory Coast, which has also been affected, have been deployed to help airlift government-provided food and medical supplies to the needy.

Neighboring Ghana has also been heavily hit, with three regions in the north of the country, traditionally its breadbasket, declared an official disaster zone after whole towns and villages were submerged. Torrential rains between July and August killed at least 18 persons and displaced a quarter of a million, Information Minister Oboshie-Sai Cofie said on Saturday.

"It is a humanitarian disaster. People have nowhere to go. Some of them are just hanging out there waiting for help to come," Cofie said. However, she said that the Ghanian government had received considerable aid and hoped the situation would improve.

In Burkina Faso, Amade Belem, who heads the country's national emergency management agency, said maize and millet farms were ruined but, "our main concern is rehousing the population. We need food and medical supplies because it goes without saying that the conditions in which these people are living, there will be no shortage of disease."

Five of the country's 13 regions have been affected and local media say the floods are the worst here since 1954.

In the oil giant of Nigeria, 68 people have died and 50,000 are affected, according to the Red Cross. Even the desert nations of Niger, Mali and Mauritania have been hit.

In some parts of Africa, local officials say deforestation has exacerbated the problem.

Charles Ngiratware, the mayor of western Nyabihu district, said nearby Gishwati forest used to hold in far more floodwater and flash floods were not common. The forest was 21,000 hectares in size in 1981, but pressure to clear land for farming means it was only 600 hectares by 2002.

"The reason the rains devastated this district is because of the deforestation of Gishwati natural forest," he said. Fifteen people, mainly women and children, have drowned after flash floods in his district this week.