BEIJING - China's Health Ministry warned Friday that the swine flu outbreak in the country could peak over the next several months, especially as hundreds of millions of people return home for the traditional Chinese New Year.

"Large numbers of travelers during the Lunar New Year period in late January and February may hamper our efforts to control the spread of the flu," ministry spokesman Deng Haihua said in a statement.

More than 100,000 people in China have been infected with swine flu, and the number of swine flu deaths more than tripled in two weeks near the end of November with the onset of winter, according to the official Xinhua News Agency.

The Health Ministry reported 326 fatalities as of Wednesday. The figures are much lower than those reported in the United States, where swine flu has sickened about 50 million Americans and killed about 10,000, according to new estimates released by federal health officials on Thursday.

China's peak flu season, which could last from now until March, will be a critical period for flu control and prevention, Deng said.

Since September, China has vaccinated more than 30 million people. The number will likely swell among vulnerable groups such as migrant workers and children in the next two months under an H1N1 prevention and control plan, Deng said.

An average of 1 million people are vaccinated every day, and the ministry aims to increase that to 1.5 million before the Lunar New Year, Deng said.

Swine flu accounted for about 91 percent of all flu cases in recent weeks.