Measles campaign backlash shows Mao's China has gone

• In Mao Zedong's time there was little scope for protest

Since the Health Ministry announced the World Health Organisation-backed measles vaccination plan last week, authorities have been flooded with queries and internet bulletin boards have been plastered with worried messages. Conspiracy theories saying the vaccines are dangerous have spread by mobile phone text messages.

The public scepticism has even been covered by state-run media, which noted the lack of trust was about more than vaccines.

"Behind the public's panic over the rumours is an expression of the citizens' demands for security and a crisis in confidence," a columnist wrote in the Chongqing Daily newspaper.

"The lack of trust toward our food and health products was not formed in one day," said the Global Times newspaper. "Repairing the damage and building credibility will take a very long time."

In recent years, government agencies have dragged their feet or withheld information about the spread of SARS, bird flu and, last month, an outbreak of cholera. China's slow response to SARS was widely blamed for causing the outbreak that swept the globe in 2003, and led to deep mistrust both internally and internationally.

Milk products contaminated with industrial chemicals are still turning up despite a scandal two years ago in which tainted infant formula sickened 300,000 babies and killed at least six.

Feeding into worries about the measles vaccine were media reports in March that vaccines for encephalitis, hepatitis B and other diseases possibly killed four children and seriously sickened dozens in one province.

The ministry has tried to calm the public's anxieties about the 10-day measles immunisation drive, which started on Saturday. It has issued statements, denied rumours and held briefings to emphasise the need for the vaccine as well as its safety.

The public outcry marks a turnaround from the mass campaigns in the communist heyday under Mao Zedong and shows how prosperity and greater access to information are creating a more assertive populace.

"This campaign would have been no problem in the Mao era, but today we know with globalisation, the internet, the information explosion, this increasingly assertive civil society, they want to participate in the public policy process," said Yanzhong Huang, senior fellow for global health at the Council on Foreign Relations in New York.