Most East Asian and Pacific countries have succeeded in fighting hepatitis B through massive vaccination, the World Health Organization (WHO) said Thursday.

The WHO's Western Pacific Region office -- which covers countries in East Asia and the Pacific including China, Australia and Papua New Guinea -- said it's observing World Hepatitis Day ( which will be held July 28) by celebrating the region's success in fighting hepatitis B.

"Our member states are committed to reducing hepatitis B infection rates in children to less than 2 percent by 2012. I'm pleased that most have already met this milestone," WHO Regional Director for the Western Pacific Dr. Shin Young-soo said in a statement.

Australia, China, New Zealand, Japan and Fiji are among the countries that managed to meet the 2012 target.

The Western Pacific Region was the first of the six WHO regions to set a deadline for the reduction of hepatitis B infection rates in children through vaccination. This is because the region accounts for about half of the world's hepatitis B cases -- with an estimated 160 million people infected by hepatitis B virus. Most were infected during birth or early childhood.

Despite the region's success in reducing the prevalence of hepatitis B, Shin said the WHO still needs to expand its effort to control the other hepatitis viruses.

Over 360,000 people die each year in the region because of chronic hepatitis B virus or HBV infection. Hepatitis C also infects more than 60 million people in the region, but there is still no vaccine available to fight the hepatitis C virus.

"Given the high endemicity of hepatitis viruses in the region -- especially hepatitis B and C -- we need to deliver focused, concerted actions, including prevention, screening and treatment of those already infected," Shin said.