BEIJING, July 24 -- China has won praises from WHO after reaching its goal to control hepatitis B infection among children through immunization ahead of schedule, but more effort is urged for its adult patients.

The National Health and Family Planning Commission announced on Friday that the prevalence of hepatitis B surface antigen, a key index indicating hepatitis B virus (HBV) infection, for Chinese children in the 1-4 and 5-14 age groups both decreased by more than 60 percent from 2006 to 0.32 and 0.94 percent respectively.

This means the country has reached the goal set by the WHO to reduce HBV infection prevalence in children to less than one percent ahead of the deadline of 2017, making the current generation of children the first in the country's history to be almost hepatitis B-free.

Viral hepatitis is a severe health threat and the leading cause of cirrhosis of the liver and liver cancer. China has about 90 million people living with chronic hepatitis B. China started its hepatitis B vaccination program in 1992, focusing on children under 15.

"Slashing the rate of hepatitis B infection in children means China has drastically reduced this generation's chances of developing conditions like cirrhosis of the liver and liver cancer later in life. This is an extraordinary public health success story," said WHO China Representative Bernhard Schwartlander on Friday.

Meanwhile, Jia Jidong, a hepatopathy expert with the Beijing Friendship Hospital under the Capital Medical University, noted a large number of Chinese adults are infected by hepatitis B, citing problems including inconsistent treatments and high medicine cost.

"Many adult patients were not able to follow through long-term use of high-end drugs due to various reasons, which held back treatment," Jia said, adding that the country's hepatitis B prevention and control task is arduous.

Dr Schwartlander also called for "the same determined, evidence-based, public health approach which created China's highly successful hepatitis B vaccination program" to be adopted for the treatments of the country's adult patients".