Advanced Registered Nurse Practioner Providing Company Nurse Staffing Recruitment Company
Independent Nurse Contractor   

Key Flu Indicators

Each week CDC analyzes information about influenza disease activity in the United States and publishes findings of key flu indicators in a report called FluView. During the week of September 6-12, 2009, a review of the key indictors found that influenza activity continued to increase in the United States compared to the prior weeks. Below is a summary of the most recent key indicators:

  • Visits to doctors for influenza-like illness (ILI) are increasing nationally. Visits to doctors for influenza-like illness are higher than what is expected during this time of year and have increased for five consecutive weeks now. This is very unusual for this time of year.
  • Total influenza hospitalization rates for adults and children are similar to or lower than seasonal influenza hospitalization rates depending on age group, but are higher than expected for this time of year.
  • The proportion of deaths attributed to pneumonia and influenza (P&I) was low and within the bounds of what is expected at this time of year.
  • Twenty-one states are reporting widespread influenza activity at this time. They are: Alabama, Alaska, Arizona, Arkansas, Florida, Georgia, Illinois, Kansas, Kentucky, Louisiana, Maryland, Minnesota, Mississippi, Nevada, New Mexico, North Carolina, Oklahoma, Pennsylvania, South Carolina, Tennessee, and Virginia. Any reports of widespread influenza activity in September are very unusual.
  • Almost all of the influenza viruses identified so far are 2009 H1N1 influenza A viruses. These viruses remain similar to the viruses chosen for the 2009 H1N1 vaccine, and remain susceptible to the antiviral drugs oseltamivir and zanamivir with rare exceptions.

Learn more >> 

U.S. Situation Update
Weekly Flu Activity Estimates

U.S. Patient Visits Reported for Influenza-like Illness (ILI)

U.S. Influenza-like Illness (ILI) Reported by Regions

U.S. Influenza and Pneumonia-Associated Hospitalizations
and Deaths, August 30 - September 12, 2009

Posted September 18, 2009, 11:00 AM ET
Data reported to CDC by September 15, 2009, 12:00 AM ET

Cases Defined by



Influenza and Pneumonia Syndrome*



Influenza Laboratory-Tests**







*Reports can be based on syndromic, admission or discharge data, or a combination of data elements that could include laboratory-confirmed and influenza-like illness hospitalizations.

**Laboratory confirmation includes any positive influenza test (rapid influenza tests, RT-PCR, DFA, IFA, or culture), whether or not typing was done.

This table is based on data from a new influenza and pneumonia hospitalizations and deaths web-based reporting system that will be used to monitor trends in activity. This is the second week of data from this new system and reflects reports by 39 of 56 jurisdictions this week. The table shows aggregate reports of all influenza and pneumonia-associated hospitalizations and deaths (including 2009 H1N1 and seasonal flu) since August 30, 2009 received by CDC from U.S. states and territories. This table will be updated weekly each Friday at 11 a.m. For the 2009-2010 influenza season, states are reporting based on new case definitions for hospitalizations and deaths effective August 30, 2009.
CDC will continue to use its traditional surveillance systems to track the progress of the 2009-2010 influenza season. For more information about influenza surveillance, including reporting of influenza-associated hospitalizations and deaths, see Questions and Answers: Monitoring Influenza Activity, Including 2009 H1N1.
The number of 2009 H1N1 hospitalizations and deaths reported to CDC from April – August 2009 is available on the Past Situation Updates page.
For state level information, refer to state health departments.
International Human Cases of 2009 H1N1 Flu Infection
See: World Health Organization.

For more information about the U.S. situation, see the 2009 H1N1 Flu U.S. Situation Update page.

International Situation Update
This report provides an update to the international situation as of September 18, 2009. As of September 13, 2009, the World Health Organization (WHO) regions have reported more than 296,471 laboratory-confirmed cases of 2009 H1N1 influenza virus (2009 H1N1) with at least 3,486 deaths, which is an increase of at least 18,864 cases and 281 deaths since September 6th. The laboratory-confirmed cases represent a substantial underestimation of total cases in the world, as many countries focus surveillance and laboratory testing only on people with severe illness. The 2009 H1N1 influenza virus continues to be the dominant influenza virus in circulation in the world. Since April 2009, 60.7% of influenza specimens reported to WHO were 2009 H1N1 viruses. In temperate regions of the Southern Hemisphere, disease due to 2009 H1N1 is largely declining. In tropical regions, there is still substantial disease due to 2009 H1N1. In temperate regions of the Northern Hemisphere, there is some increased disease activity due to 2009 H1N1, including in parts of the United States, Canada and Europe.
For more information about the U.S. situation, see the 2009 H1N1 Flu International Situation Update page.

Recent Updates of Interest

Additional Updates on the CDC H1N1 Flu Website
To learn about other recent updates made to the CDC H1N1 Flu Website, please check the "What's New" page on the CDC H1N1 Flu website.



JCAHO Certified Advanced Registered Nurse Practitioner