SHANGHAI, Nov. 29 (Xinhua) -- The number of reported cases of HIV infections in Shanghai in the first 11 months of this year increased by 74 percent from the same period last year, the Shanghai municipal health bureau said on Wednesday.

    As of Nov. 20, the number of officially recorded new HIV cases reached 621, bringing the total to 2,261, of whom 97 died.

    High-risk groups including sex workers and drug addicts were the major sources of infection, the report said.

    The bureau said most of the victims were aged between 25 and 44 and more than 80 percent were male.

    Of the 621 HIV-carriers, 499 were migrants from 23 mainland provinces and municipalities as well as Taiwan.

    The virus was mainly spread through unsafe sex among local residents and migrant workers were mainly infected by shared drug needles, the report said.

    Shanghai, a city of more than 20 million including migrant people, recorded 356 new HIV cases last year. It reported its first HIV case in 1987.

    China's Ministry of Health said last week that the number of people officially reported as infected by HIV had risen 27.5 percent since the beginning of the year.

    By the end of October, a total of 183,733 people had been officially reported to have contracted HIV, 39,644 more than at the end of 2005, the ministry said.