BEIJING (Reuters) - A farmer in China's southeastern province of Fujian has been infected with the H5N1 form of bird flu, state media said on Thursday, the first human case in the country in about seven weeks.

The 44-year-old woman from Jianou city was being treated in hospital, according to the official Xinhua news agency.

"Tests by the Chinese Center for Disease Control and Prevention on the patient have confirmed that the patient has been infected with the bird flu virus strain H5N1," it said.

The Ministry of Health confirmed the news on its Web site (www.moh.gov.cn) but gave no other details.

The Ministry of Agriculture said an investigation team it sent down to the woman's village found no trace of the virus in poultry samples.

"The initial analysis is that we cannot rule out the possibility of infection through contact with a virus-carrying wild bird," it said in a statement on its Web site (www.agri.gov.cn).

The ministry added it was stepping up poultry vaccinations, and had sealed off the woman's house and surrounding area while it was disinfected.

Hong Kong's government also said it had been notified by mainland authorities of the new case.

The Department of Health in Hong Kong said in a statement it was maintaining close contacts with its Chinese counterpart and hoped to obtain more information.

China's last confirmed human case was reported in January. The farmer, from eastern Anhui province, recovered.

China has now reported a total of 23 human cases of bird flu, including 14 deaths, since 2003 and, with the largest poultry population and millions of backyard birds roaming free, it is seen as central to the fight against the virus.