BEIJING -- China plans to offer free treatment to impoverished cataract patients, according to a plan published Wednesday.

The poverty alleviation and health authorities are building a long-term mechanism to cover all cataract patients living in poverty by 2020.

The plan specifies requirements for hospitals, patients and monitoring quality of cataract surgeries.

Cataracts are the primary cause of blindness in China, and increasing numbers of young people suffering from them.

The Cataract Surgery Rate (CSR), the number of procedures per million people, went over to 1,500 in 2015 in China.

The number is expected to reach 2,000, according to the national project for eye health by 2020.

China had spent over $100 million on cataract surgery by 2014, according to World Health Organization.

In addition, a mobile hospital called Lifeline Express has helped more than 180,000 cataract patients since 1997.