The Chinese mainland saw a spike in H1N1 flu cases during the weekend, with 1,598 infections confirmed between Friday and Monday.
The new cases bring the mainland's cumulative total to 9,103, said the Ministry of Health.
Of the total number, 5,350 people have fully recovered. The rest are undergoing treatment. No deaths have been reported, the ministry added.
Among the new cases, 14 people were infected overseas. The rest picked up the illness on the Chinese mainland.
All 31 provincial areas have now reported H1N1 cases.
Experts have said the outbreak will peak in the fall and winter.
More than 60 percent of China's total H1N1 cases were confirmed in the past three weeks, suggesting the outbreak is gaining momentum.
"It is to be expected, the soaring number of confirmed cases, because the country has now entered the peak season of the deadly disease," said Guan Yi, a microbiology professor with the University of Hong Kong.
Current predictions suggest tens of millions nationwide will get the disease, said Liang Wannian, deputy director of the ministry's emergency office.
The potentially deadly strain of the flu virus has infected more than 277,600 people worldwide, killing at least 3,200, according to the World Health Organization's latest statistics.
Last week, the Chinese Center for Disease Control and Prevention approved the use of China's H1N1 vaccine, making it the first nation to be ready with vaccinations.
Despite the apparent acceleration of the disease, China has no plans to bring forward its inoculation program, which is scheduled for next month, a ministry official said.
"Our ministry has not planned to change its original national inoculation plan or other preventive and control measures released last week," said the press officer, surnamed Zhao.
Xinhua contributed to the story