H1N1(Swine Flu): So How Is It Looking? U.S. Now In Week Ten Of Wave Two

October 24, 2009

For those of us keeping track, this is week ten, wave two…every Friday, CDC publishes the weekly summary of where we are nationally in the pandemic…if you don’t visit this site, bookmark it and check it out weekly, late Friday or Saturday morning. http://www.cdc.gov/flu/weekly/

WEEK TEN, WAVE TWO: THE NET – NET

  • THE circulating virus nationally is H1N1 – we have yet to see seasonal flu.
    • All subtyped influenza A viruses being reported to CDC were 2009 influenza A (H1N1) viruses.
  • The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
  • Eleven influenza-associated pediatric deaths were reported.
    • Nine of these deaths were associated with 2009 influenza A (H1N1) virus infection and two were associated with an influenza A virus for which subtype is undetermined.
  • The proportion of outpatient visits for influenza-like illness (ILI) was above the national baseline. All 10 regions reported ILI above region-specific baseline levels.
  • Forty-six states reported geographically widespread influenza activity, Guam and three states reported regional influenza activity, one state, the District of Columbia, and Puerto Rico reported local influenza activity, and the U.S. Virgin Islands did not report.

PNEUMONIA AND INFLUENZA HOSPITALIZATION AND DEATH TRACKING

A new system for tracking cases was implemented on August 30, 2009, and replaced the weekly report of laboratory confirmed 2009 H1N1-related hospitalizations and deaths that began in April 2009.

Jurisdictions now report to CDC either laboratory confirmed or pneumonia and influenza syndromic-based counts of hospitalizations and deaths resulting from all types or subtypes of influenza, not just those from 2009 H1N1 influenza virus. (Remember the only influenza virus in the US is H1N1)
Jurisdictions now report to CDC either laboratory confirmed or pneumonia and influenza syndromic-based counts of hospitalizations and deaths resulting from all types or subtypes of influenza, not just those from 2009 H1N1 influenza virus. (Remember the only influenza virus in the US is H1N1)
  • To allow jurisdictions to implement the new case definition, counts were reset to zero on August 30, 2009. From August 30 – October 17, 2009
    • 8,204 laboratory-confirmed influenza associated hospitalizations
    • 411 laboratory-confirmed influenza associated deaths
    • 21,823 pneumonia and influenza syndrome-based hospitalizations
    • 2,416 pneumonia and influenza syndrome-based deaths, were reported to CDC.
    • CDC will continue to use its traditional surveillance systems to track the progress of the 2009-10 influenza season.

PNEUMONIA AND INFLUENZA (P&I) MORTALITY SURVEILLANCE

During week 41, 6.9% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 6.6% for week 41. Including week 41, P&I mortality has been above threshold for three consecutive weeks.
During week 41, 6.9% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 6.6% for week 41. Including week 41, P&I mortality has been above threshold for three consecutive weeks.

INFLUENZA-ASSOCIATED PEDIATRIC MORTALITY

A total of 95 deaths in children associated with 2009 H1N1 virus have been reported to CDC.

Eleven influenza-associated pediatric deaths were reported to CDC during week 41 (Georgia [2], Hawaii, Louisiana, Oklahoma [2], Ohio, North Carolina, Oregon, Texas, and Virginia). Nine of these deaths were associated with 2009 influenza A (H1N1) virus infection and two were associated with an influenza A virus for which the subtype is undetermined.

Since August 30, 2009, CDC has received 53 reports of influenza-associated pediatric deaths that occurred during the current influenza season (three deaths in children less than 2 years, seven deaths in children 2-4 years, 21 deaths in children 5-11 years, and 22 deaths in individuals 12-17 years). Forty-seven of the 53 deaths were due to 2009 influenza A (H1N1) virus infections, and the remaining six were associated with influenza A virus for which the subtype is undetermined.
Since August 30, 2009, CDC has received 53 reports of influenza-associated pediatric deaths that occurred during the current influenza season (three deaths in children less than 2 years, seven deaths in children 2-4 years, 21 deaths in children 5-11 years, and 22 deaths in individuals 12-17 years). Forty-seven of the 53 deaths were due to 2009 influenza A (H1N1) virus infections, and the remaining six were associated with influenza A virus for which the subtype is undetermined.

OUTPATIENT ILLNESS SURVEILLANCE

Nationwide during week 41, 7.1% of patient visits reported through the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet) were due to influenza-like illness (ILI). This percentage is above the national baseline of 2.3%.
Nationwide during week 41, 7.1% of patient visits reported through the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet) were due to influenza-like illness (ILI). This percentage is above the national baseline of 2.3%.

ITS EVERYWHERE, ITS EVERYWHERE

During week 41 influenza activity was "widespread" in the US.
During week 41 influenza activity was "widespread" in the US.
  • Widespread influenza activity was reported by 46 states (Alabama, Alaska, Arizona, Arkansas, California, Colorado, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, and Wyoming).
  • Regional influenza activity was reported by Guam and three states (Connecticut, New Jersey, and South Carolina).
  • Local influenza activity was reported by the District of Columbia, Puerto Rico, and one state (Hawaii).
  • The U.S. Virgin Islands did not report.

As the vaccine becomes available in your area, please consider taking it, especially if you are in the higher risk groups – for yourself, your family and your community.  All medications have risks this is true.  This flu is and can be serious and in some cases it kills.

http://www.cdc.gov/flu/weekly/