SAN FRANCISCO, June 11 (Xinhua) -- Another middle-aged man in California's Alameda County has died from the A/H1N1 flu, representing the second such death in the county and the third in San Francisco Bay Area, local health officials announced on Thursday.

    The man "had been hospitalized for other conditions prior to his death," Alameda County Public Health Department said in a statement, without giving further details.

    The county reported its first H1N1 flu death on Tuesday, which also involved a middle-aged male.

    Last week, an elementary school-aged girl in Contra Costa County was confirmed to be the first patient died from the H1N1 flu in San Francisco Bay Area.

    Including the three victims, six H1N1 flu-related deaths have been reported so far in California, the most populous state in the United States.

    The latest death in San Francisco Bay Area was announced on the same day after the World Health Organization (WHO) declared that the widely spreading H1N1 influenza has developed into a global pandemic, raising its pandemic alert to the highest level of six.

    As of Thursday, 74 countries and regions have officially reported 28,774 cases of the H1N1 influenza infections to the WHO, including 144 deaths.

    The raising of the pandemic alert level by the WHO reflects the novel H1N1 flu's geographic presence in more places around the world, "but does not signify an increase in the flu's severity," Mark Horton, director of the California Department of Public Health, commented in a statement on Thursday.

    "While there have been hospitalizations and deaths from the virus in California, and we expect there will be more, for most people who contract the virus the symptoms have been mild," he noted.

    Horton recommended that to combat the spread of the H1N1 virus, the public should continue to take basic precautions such as washing hands, coughing in sleeve and staying home when sick.