It appears from the data released on Jan. 17 for the week ending Jan. 11 that America's annual seasonal flu season has peaked. The data from the Centers for Disease Control (CDC) shows that outpatient influenza-like illness have dropped for the second week in a row to 3.6 percent of all outpatient visits. The high, seen in the week ending Dec. 28, 2013, was 4.6 percent. The season is not over and it is still possible for the trend to reverse itself.
The CDC has warned for some weeks about the unusual nature of the 2013-2014 flu season. The primary strain being detected across the county is the 2009 A(H1N1), which is the pandemic strain from 2009-2010. The CDC has received reports from the states showing that 96.8 percent of all flu samples typed were A strains. Of the 22,469 specimens tested test for type of flu, 56.6 percent were 2009 A(N1H1), 2 percent were an A (H3) virus and 38.2 percent were an A strain and not subtyped. B strains of the influenza virus have been found just 3.2 percent of the time.
The pandemic flu was notable for largely skipping the elderly, an age group normally hit heavily by the seasonal flu. That is holding true again this year as the greatest number of people being hospitalized are in the 18 to 49 and the 50 to 64 age ranges. Patients ages 18 to 49 are being hospitalized in numbers not seen since the pandemic. Patients 50 to 64 are being hospitalized in greater numbers than during the pandemic, or in the years since.
Obesity is the number one underlying factor in adults being hospitalized with influenza, seen in 45 percent of adult patients. Pregnant women account for 22 percent of flu hospitalizations. The CDC reports that the demographics of patients being hospitalized this season most closely resemble those from the pandemic.
The flu is geographically widespread in 40 states. ILI activity is moderate to high in 26 states and low or minimal in 24 states. While influenza is being seen throughout the nation, the number of illnesses seems to have room to increase in many states. The 2013-2014 flu vaccine continues to be an excellent match for the influenza viruses in circulation and it is not too late to be immunized.
Through Jan 11, 20 children have died from influenza or its complications in the U.S. The CDC states:
Of the 20 pediatric deaths this week, 17 were eligible to receive flu vaccine. Of the 15 children who were eligible for vaccination and for whom CDC had a vaccination history, only one was fully vaccinated against influenza. These deaths are a somber reminder of the danger flu poses to children.