# 4148
The CDC has posted FluView for week 48, ending December 5th , 2009. The amount of flu activity we are seeing has decreased again for the sixth straight week after four consecutive weeks of sharp gains, but is still higher than normally seen this time of year.
P&I (pneumonia & Influenza) deaths increased over last week and remain above the epidemic level for this time of year, and 16 pediatric influenza-related deaths were added last week.
While the numbers here in the US, and also in Canada, reflect a winding down of the fall pandemic wave, what lies ahead is less clear. There are almost 5 more months remaining in flu season, and there are a number of possible scenarios (see Waiting For The Other Flu To Drop).
We’ll just have to wait to see. In the meantime, we’ll take any respite we can get.
I’ve excerpted some of the data and graphs below, but follow the link to read it in its entirety.
2009-2010 Influenza Season Week 48 ending December 5, 2009
All data are preliminary and may change as more reports are received.
Synopsis:
During week 48 (November 29-December 5, 2009), influenza activity continued to decrease in the U.S
- 478 (8.9%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
- Over 99% of 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 for the tenth consecutive week.
- Sixteen influenza-associated pediatric deaths were reported. Thirteen of these deaths were associated with 2009 influenza A (H1N1) virus infection, two were associated with an influenza A virus for which the subtype was undetermined, and one was associated with an influenza B virus infection.
- The proportion of outpatient visits for influenza-like illness (ILI) was 2.7% which is above the national baseline of 2.3%. Six of the 10 regions reported ILI at or above region-specific baseline levels. Regions 3, 6, 8 and 10 reported ILI below their region specific baselines.
- Fourteen states reported geographically widespread influenza activity, Puerto Rico and 25 states reported regional influenza activity, the District of Columbia and seven states reported local influenza activity, and the U.S. Virgin Islands, Guam and four states reported sporadic influenza activity.
U.S. Virologic Surveillance:
WHO and NREVSS collaborating laboratories located in all 50 states and Washington D.C., report to CDC the number of respiratory specimens tested for influenza and the number positive by influenza type and subtype. The results of tests performed during the current week are summarized in the table below.
Pneumonia and Influenza (P&I) Mortality Surveillance
During week 48, 7.8% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 7.1% for week 48. Including week 48, P&I mortality has been above threshold for 10 consecutive weeks.
Influenza-Associated Pediatric Mortality
Sixteen influenza-associated pediatric deaths were reported to CDC during week 48 (Alabama, Arizona [2], California [3], Colorado, Minnesota [4], Missouri [2], New Mexico, North Carolina, and Virginia). Thirteen of these deaths were associated with 2009 influenza A (H1N1) virus infection, two were associated with an influenza A virus for which the subtype is undetermined, and one was associated with an influenza B virus infection. The deaths reported during week 48 occurred between August 9 and December 5, 2009.
One death associated with 2009 influenza A (H1N1) virus infection reported during week 48 occurred in August during the 2008-09 season, bringing the total number of reported pediatric deaths occurring during that season to 129.
