Buildings are partially submerged after heavy rains hit Lianzhou, in China's southern Guangdong province. Rains have inundated roads, houses and farmland throughout many regions of China. More than 100 people died over the past week. ((Associated Press))

Flooding and landslides in China during one of the country's deadliest rainy seasons in decades killed at least 100 people and forced tens of thousands out of their homes in the east.

The government-run Xinhua news agency said Sunday that the intense flooding in the past week has affected half of China, wreaking havoc on thousands of hectares of farmland and leaving more than 4,000 homes in ruins.

Meanwhile, dikes are in danger of spilling over.

Xinhua said China's third-longest River, the Huai, has swelled and is expected to stay at a dangerously high level for at least another 10 days. In the Henan, Anhui and Jiangsu provinces — regions that are within the path of the Huai's floodwaters — more than one million people were forced to evacuate.

China's Ministry of Health ordered local health departments on Monday to intensify disease prevention in the country's flood-stricken areas. Four medical services teams arrived at Jiangsu and Anhui on July 18.

In a report, Xinhua quoted a flood-control official with Anhui province as saying that "the dikes that have soaked in high water for 19 days will be at increased risk of breach in the coming 10 days."

In order to ensure that no fatal epidemic diseases break out, the health ministry has required all provincial health departments to report daily with their disease monitoring results.

The Chinese government has pledged 39.88 million yuan ($5.5 million Cdn) for disease control in the areas hit by the floods.

During last year's rainy season, which typically begins in June, 2,704 people died.

With files from the Associated Press