A second person has died in the city after being infected with H7N9 bird flu. The 65-year-old Hong Kong man died yesterday in Queen Mary Hospital. He was the third person in Hong Kong to have become infected with the virus since last month. All are believed to have contracted the disease in Shenzhen. The most recent victim had travelled to the Luohu district on January 1 and returned to Hong Kong the next day. It was the third death this year from H7N9. A 75-year-old Zhejiang woman died on Saturday and a middle-aged Guangdong man died last Monday. The development came amid news that nine other people had died after contracting more common strands of flu this year. During the winter peak period, 25 people, including two children, required intensive care. The Centre for Health Protection yesterday disclosed a fourfold increase in the number of people being infected. Urging vigilance, centre director Dr Leung Ting-hung said H1N1 swine flu was the dominant virus strain circulating in the city, but influenza A sub-type H3N2 was becoming more common. Last week, the centre received reports of 490 flu infections, almost four times the 130 cases a week it recorded at the end of December. "The weekly influenza-like illness consultation rates among both general outpatient clinics and private doctors have steadily increased in the past few weeks," Leung said. "The public is reminded to remain vigilant in prevention of seasonal influenza, especially the elderly, children and those who suffer from long-term illness." He urged vaccination as the virus could case serious complications, especially among vulnerable groups. The number of flu outbreaks in kindergartens, schools and old people's homes increased to seven last week, up from two in the previous week. H1N1 was responsible for almost half of all cases. But H3N2, which accounted for just under 30 per cent, was responsible for most cases last week. More people are getting flu jabs this year, according to data from the centre. As of January 12, 421,000 doses of seasonal influenza vaccines had been administered under the Vaccination Subsidy Scheme and the Government Vaccination Programme - 38,000 more than a year ago.