A factory worker from Sanming City, Fujian province, is the seventh human case of H5N1 bird flu in China and the third fatality, the Ministry of Health reported Thursday. The 41-year-old woman showed symptoms of fever and pneumonia on December 6, was hospitalized two days later and died on December 21. Meanwhile a prominent US virologist said Thursday China was most likely using substandard poultry vaccine or not enough good vaccine, explaining recent outbreaks of the virus in poultry, Reuters reported.