HOUSTON, Sept. 25 (Xinhua) -- The federal Centers for Disease Control and Prevention (CDC) on Friday reported that 572 people had died of influenza and pneumonia-associated complications in the past week, bringing the death toll to 936 since the beginning of September.

    Meanwhile, according to the latest statistics released by the CDC, 5,486 people across the country have been admitted last week to hospitals resulting from all types or subtypes of influenza, not just those from the A/H1N1 influenza virus, bringing the total number to 10,082.

    In an effort to add additional structure to the aggregate reporting, the Council of State and Territorial Epidemiologists (CSTE) and the CDC have developed new case definitions for influenza-associated hospitalizations and deaths to be applied for the 2009-2010 influenza season, formally beginning from Oct. 4.

    This new system was implemented on Aug. 30, 2009 and replaces the weekly report of laboratory confirmed A/H1N1-related hospitalizations and deaths since July.

    States can now report to the CDC either laboratory confirmed or pneumonia and influenza syndromic hospitalizations and deaths resulting from all types or subtypes of influenza. To allow states to implement the new case definition, counts were reset to zero by the CDC on Aug. 30, 2009.

    The CDC said the latest data, based on reports by U.S. States and territories on Sept. 22, shows that 26 states had geographically widespread influenza activity in the past week, comparing to 21 states in the previous week.

    The five more states that had widespread influenza activity include the most populous states of California and Texas. Meanwhile, four more states had regional influenza activity in the past week, bringing the total to 11.

    All these indicate the second wave of the pandemic is imminent.

    The seasonal influenza A (H1) and A (H3) viruses co-circulated at low levels with the A/H1N1 virus, the CDC said in a conclusion, adding that 99 percent of all subtyped influenza A viruses being reported to the CDC last week were the new A/H1N1 virus.

    However, the CDC said that, during the first three weeks in September, all deaths reported through the 122-Cities Mortality Reporting System due to pneumonia and influenza (P&I) was 6.1 percent, a little over 6.0 percent in the previous week, but still below the epidemic threshold of 6.3 percent, the CDC explained on its website.

    Nationwide, 4.6 percent of patient visits -- comparing to 4.4 percent in the previous week -- were due to influenza-like illness(ILI), according to the CDC experts, who point out to the fact that this percentage more than doubles the national baseline of 2.4 percent.

    The A/H1N1 virus infection was first identified in the United States in late April. By August, 555 people had died of the new virus with hospitalizations of 8,842. More than 40,000 confirmed and probable cases had been reported and more than 1 million infections were estimated to have occurred in the United States.

    The CDC and state officials are preparing for massive A/H1N1 flu immunizations, starting with school children in the first week of October.

Special Report:  World Tackles A/H1N1 Flu