As hepatitis carriers were celebrating World Hepatitis Day on Saturday, seeking to raise more awareness about the disease, one of their main sources of support went down. Ahead of the day, a well-known public welfare website dedicated to preserving rights and interests of hepatitis B carriers (HB carriers) was blocked in China.

The sudden closure of Gandanxiangzhao, a BBS where hepatitis carriers can communicate freely, has sparked fury among hepatitis carriers and public health NGOs.

The Beijing Yirenping Center, a non-profit organization operating the website, wrote a public letter to the Ministry of Industry and Information Technology on Friday, demanding that the situation be looked into and the website unblocked.

"Over the past weeks, it was difficult to log on and the website has been unavailable since Friday," Lu Jun, head of the center, told the Global Times.

The reason it was blocked remains unknown, as calls to the Ministry of Industry and Information Technology went unanswered as of press time.

Launched in 2001, the website has become an important channel among hepatitis carriers.

"It is the biggest public platform available for HB carriers to share their experience and extend mutual comfort and care. It was a spiritual home for us. We are saddened by this," Lei Chuang, an HB carrier, told the Global Times.

The website also seeks to eliminate discrimination against HB carriers and has started numerous social campaigns to protect their rights and interests, Lei said.

This is not the first time the website has been blocked. "It was blocked twice in 2007 and 2008," Lu said. "It was unblocked shortly after the Yirenping Center answered questions from the government."

The website remained blocked as of Sunday midnight.

Around 93 million Chinese people are infected with the HB virus, and 70 percent of them are HB carriers, statistics from the Ministry of Health showed.

Although it has been proven that HB can only be transmitted via blood or sex, discrimination remains common.

Almost half of all carriers say they have been fired or forced to drop out of school after being discovered they have the virus in their blood, said the Chinese Medical Association.

A subsidiary of the State-owned Aviation Industry Corporation of China in Chengdu came under fire for testing 350 job applicants for HB.

It found eight were carriers and the company refused to hire them.

In a statement released Sunday, the company said it put the eight carriers on paid medical leave, even if they are not sick.

Testing for HB by schools and employers was banned by the government in February 2010.