SHANGHAI (AP) — The government has licensed a science institute in Shanghai to begin producing a single-dose swine flu vaccine, raising the number of such manufacturers in China to three, an official said Wednesday. The official at the public affairs office of Shanghai's Food and Drug Administration confirmed that the government-affiliated Shanghai Institute of Biological Sciences would begin mass production of the vaccine. Like many Chinese officials, he refused to give his name. The institute plans to produce 3 million doses of the vaccine by Oct. 1, China's National Day, and 10 million by the end of the year, the state-run newspaper Shanghai Daily reported. It said the Shanghai Health Bureau was awaiting Health Ministry approval of vaccination plans calling for the shot to be administered at no cost to people age 3 and over. Students, medical workers, the elderly and staff working at next year's May 1-Oct. 31 World Expo would be given priority, the report said, citing Expo official Song Guofan. Sinovac Biotech Ltd. in Beijing and Hualan Biological Engineering Inc., in central China's Henan province, were already approved to make the vaccine. China's health authorities have approved use of vaccines using a single dose to fight the swine flu. The World Health Organization has said it was encouraged after reviewing test details from Beijing Sinovac, though experts say more results are needed to determine if one dose would be potent enough. China is still reviewing several more vaccines and aims to have enough doses to innoculate 5 percent of the public by the year's end. Stockpiling vaccines is China's latest move in its aggressive approach to contain the spread of swine flu in the country of 1.3 billion people and relatively limited medical resources. The Health Ministry reported that as of Monday 9,103 cases of swine flu had been reported in mainland China, with no fatalities directly related to the illness.