China will have reserves of 26 million A/H1N1 flu vaccine shots at the end of October, according to a news briefing jointly held by the Ministry of Health (MOH) and the Chinese Center for Disease Control and Prevention (CDC)in Beijing Wednesday.

"The number is expected to increase to 100 million when the country finishes its second phase of production and reservation," said Deng Haihua, deputy director of general office of the MOH.

"Some 13,000 volunteers in seven provincial areas who have taken part in the testing of the A/H1N1 flu vaccination proved the domestically-made vaccine is effective in protection," said Zhao Kai, leader of the experts team for A/H1N1 flu vaccine and a member of the Chinese Academy of Engineering.

"The volunteers covered all age brackets," Zhao added. They received the first shots about two months ago and will be sampled for testing of effectiveness and term of protection in the third month.

"Generally speaking, the inoculations are safe, but we cannot rule out the possibility of adverse reactions," said Liang Xiaofeng, director of the immunization center under the China CDC.

Beijing has been leading the country in inoculation. About 39,000 residents in the city had been inoculated by Tuesday afternoon, with 14 cases of adverse reaction.

Liang said four of the 14 adverse reactions "may be" related to the vaccines.

"We are still investigating the reasons," Liang said.

Liang also said there was still uncertainty about the safety of vaccination for "sensitive groups" such as pregnant and breastfeeding women.

China is currently focusing its inoculation efforts on groups like students, teachers and patients of chronic diseases.

In response to possible adverse outcomes, China has established a system which will enable local health departments to halt inoculation if serious cases like death or deformity occurred, or there appeared an apparent tendency of mass suspected cases of adverse reactions from A/H1N1 flu vaccines.

So far, no deaths from A/H1N1 flu have been reported on the Chinese mainland, but Taiwan has reported 17 deaths, of whom two were pregnant women.

On Monday, more than 10,000 students and performers in Beijing who are to take part in the National Day parade and performances on October 1 received vaccinations, with no adverse reactions, the Beijing Municipal Bureau of Health said Tuesday.

China issued a warrant for mass inoculation with A/H1N1 flu vaccine on September 8 after it approved on September 3 vaccine produced by domestic pharmaceutical company Sinovac.

By Monday, more than 13,000 confirmed cases of A/H1N1 flu had been reported on the mainland, about 66.4 percent of whom have recovered. Among the new cases, the percentage of those infected within China had increased. There have been no deaths reported.