2009 H1N1 Flu: Situation Update, January 29, 2010

Atlanta, GA–(ENEWSPF)–January 29, 2010.

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 January 17-23, 2010, most key flu indicators remained about the same as during the previous week. Below is a summary of the most recent key indicators:

  • Visits to doctors for influenza-like illness (ILI) nationally are low.
  • Overall cumulative hospitalization rates for the 2009-10 influenza season have leveled off in all age groups and very few 2009 H1N1-laboratory confirmed hospitalizations were reported by states during the week ending January 23.
  • The proportion of deaths attributed to pneumonia and influenza (P&I) based on the 122 Cities Report increased over the previous week and is higher than expected for this time of year. This increase in P&I is thought to result from an increase in reports of pneumonia-associated deaths in older people. These deaths are not necessarily related to flu illness. In addition, another five flu-related pediatric deaths were reported this week: four of these deaths were associated with laboratory confirmed 2009 H1N1, and one death was associated with an influenza A virus for which the subtype was undetermined. Since April 2009, CDC has received reports of 312 laboratory-confirmed pediatric deaths: 262 due to 2009 H1N1, 47 pediatric deaths that were laboratory confirmed as influenza, but the flu virus subtype was not determined, and two pediatric deaths that were associated with seasonal influenza viruses. (Laboratory-confirmed deaths are thought to represent an undercount of the actual number. CDC has provided estimates about the number of 2009 H1N1 cases and related hospitalizations and deaths.
  • No states reported widespread influenza activity. Five states reported regional influenza activity. They are: Alabama, Georgia, New Jersey, South Caroline and Virginia.
  • Almost all of the influenza viruses identified so far continue to be 2009 H1N1 influenza A viruses. These viruses remain similar to the virus chosen for the 2009 H1N1 vaccine, and remain susceptible to the antiviral drugs oseltamivir and zanamivir with rare exception.

 

*All data are preliminary and may change as more reports are received.

Laboratory Confirmed Influenza-Associated Hospitalizations
and Deaths from August 30 2009 to January 23, 2010
Posted January 29, 2010, 11:00 AM ET
Data reported to CDC by January 26, 2010, 12:00 AM ET
Cases Defined by
Hospitalizations
Deaths
Influenza Laboratory-Tests** 39,387 1,857

*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.

The table shows aggregate reports of all laboratory confirmed influenza 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

**States report weekly to CDC either 1) laboratory-confirmed influenza hospitalizations and deaths or 2) pneumonia and influenza syndrome-based cases of hospitalization and death resulting from all types or subtypes of influenza. Although only the laboratory confirmed cases are included in this report, CDC continues to analyze data both from laboratory confirmed and syndromic hospitalizations and deaths.

U.S. Influenza-associated Pediatric Mortality
Posted January 29, 2010 (Updated Weekly)
Data reported to CDC by January 23, 2010
Date Reported
Laboratory-Confirmed 2009 H1N1 Influenza Pediatric Deaths
Laboratory-Confirmed Influenza A Subtype Unknown Pediatric Deaths
Laboratory-Confirmed
Seasonal
Influenza
Total
This Week  (Week 3, January 17 to January 23, 2010) 4 1 0 5
Since August 30, 2009 203 44 1 248
Cumulative since April 26, 2009 263 47 2 312

This table is based on data reported to CDC through the Influenza-Associated Pediatric Mortality Surveillance System. Influenza-associated deaths in children (persons less than 18 years) was added as nationally notifiable condition in 2004.

For more information about influenza-associated pediatric mortality, see FluView.

Source: cdc.gov