Getting up from a new toilet, Xu Meixiang simply pushed a button to flush everything in the bowl down the drain. The tank then refilled with fresh water for the next user.

While that is an everyday scene for urban residents, it was of novelty in 49-year-old Xu’s home village of Dahuaping in Huoshan county, Anhui province, a few months ago after its toilets were rebuilt or renovated to include such sanitary devices. The new toilet was built with the aid of government subsidies to free Xu’s family from mosquito bites in summer and frozen bottoms in winter.

They and 20 neighboring families were the latest beneficiaries of the toilet revolution campaign in the mountainous county last year. A new round, currently underway, will help another 50 village households.

The Ministry of Agriculture and Rural Affairs and seven other Central government departments released a guideline last week to promote a special action plan for the campaign in rural areas. By 2020, all toilets for rural families in eastern China and suburban areas in the central part of the country should be renovated or rebuilt, with human waste properly disposed of, the guideline said. In other parts of Central China and in the west of the country, around 85 percent of families should be using sanitary toilets by then.

The guideline urged stronger fiscal support for the campaign and said farmers should rebuild or renovate their toilets of their own free will. It encourages all families in each village to accomplish such renovation together.

The toilet revolution campaign was originally proposed by UNICEF to improve children’s welfare worldwide.

For decades, many people in China, especially in far-flung areas, used unsanitary open-air toilets that were a breeding ground for diseases such as malaria. Mosquitoes and flies were often seen around the toilets used by Xu and her neighbors.

China has committed itself to improving sanitation in urban and rural areas. Since 2015, the country has accelerated the campaign in tourism sites and its vast rural areas. Government subsidies for building a new toilet or renovating an old one range from 1,000 yuan ($148) to 4,000 yuan, depending on the local government’s fiscal status.

Xu’s family built the new 20,000 yuan toilet together with the families of her three siblings. They split the bill and the local government provided an 8,000 yuan subsidy after it was completed.

“Surrounded by flies and mosquitoes in summer, going to the toilet used to be distressing,” Xu said. “Now, the new facility can get us away from those insects and ‘doing the business’ is kind of enjoyable and a real relief.”

More than 200 million farmer families live in more than 550,000 villages in China, and that makes building or renovating their toilets a huge task, Minister of Agriculture and Rural Affairs Han Changfu said in October.

He said the toilet revolution is vital to improving living conditions for rural residents and enhancing their sense of happiness, adding that nearly half of the country’s farmer families have already renovated or rebuilt their toilets.

Undisposed human waste from toilets and unhygienic drinking water are responsible for about 80 percent of the spread of epidemic diseases in rural areas, said Zheng Fengtian, a professor of agriculture and rural development at Renmin University of China.

The toilet revolution is a fundamental way to improve health conditions for rural residents by effectively reducing the possibility of being infected with such diseases, he said.

For example, in Jiangxian county, Shanxi province, the campaign replaced more than 60,000 old-fashioned toilets that had no water to flush, and reduced the incidence of infectious intestinal diseases among farmers by 46 percent in 2016, Zheng said.

In addition, the campaign can boost investment in infrastructure, including water supply, electricity and roads, in rural areas and the development of rural tourism, which is helpful to improving the health and living conditions of farmers, he said.