Beijing is gearing up for a mass H1N1 flu inoculation of young students as its previous vaccination of hundreds of thousands of Chinese nationwide proved to be safe.

No "serious adverse reactions" were detected among the recipients, the country's health minister, Chen Zhu, said Monday at a press conference, without elaborating on the definition of serious adverse reaction.

After the National Day holiday, Beijing will vaccinate all primary and middle school students against the H1N1 flu, said local health authorities Monday.

The mass inoculation, which is free and voluntary, will be carried out from Oct 8 to 30 in the capital, according to a joint notice by the municipal health and education bureaus.

A student from Jingyuan School gets an A(H1N1) flu vaccine jab in Beijing September 21,2009. [Xinhua]

Each school is required to follow the principle of voluntary vaccination, said the notice.

Inoculation can only be given after getting written consent from the students' parents, it stipulates.

"The priority for inoculation is decided according to the situation in the country," Zhao Kai, a vaccine expert and academician with the Chinese academy of engineering, told China Daily Monday.

An epidemic report by the Chinese Centers for Disease Control and Prevention showed that among new infections in September, 90 percent occurred at schools as the new semester kicked off.

Nearly 100,000 National Day celebration performers, mainly students from the capital, have already been vaccinated against H1N1.

Health authorities previously reported 14 cases of mild adverse reaction.

Four of them may be related to the vaccine and an investigation into the reasons was underway, said Liang Xiaofeng, director of the immunization center under the Chinese Center for Disease Control and Prevention.

"The inoculations were safe, but the possibility of adverse reactions cannot be ruled out," he said.

In response to possible adverse effects after large-scale inoculation, China established a system enabling local health departments to halt inoculation if deaths or deformity occur, or if there are mass cases of adverse reactions, Xinhua News Agency reported.

About 16,000 confirmed cases of H1N1 flu have been reported on the Chinese mainland.

Of those, more than 71 percent have recovered. There have been nine severe cases with no deaths reported, said the Ministry of Health.

The medical cost for the patients, especially for those suffering from severe symptoms, will be compensated by the medicare system, Chen said Monday.