Only a half dozen states in the South are reporting high levels of flu activity, but from early indications, the Centers for Disease Control and Prevention is worried that this year's flu season will be severe.
"From what we know about the viruses we are seeing, we are concerned that it may be a severe year this year, particularly for people in the older age group as well as for young children," said Dr. Angela Campbell, a medical officer in the CDC's respiratory disease branch.
The concern is prompted by the type of flu strain, H3N2, that's most prevalent this year. It's the same strain that dominated during three of the most severe flu seasons since 2002, including the winter of 2012-2013. The trouble is this year's flu vaccine—developed last February—is not well-matched to combat that strain of influenza.
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"That may mean that the vaccine won't protect as well against severe outcomes such as hospitalizations or deaths," said Campbell, while cautioning that Americans should not skip the flu shot. "Vaccination is the best first line of defense."
Two years ago, the severe outbreak resulted in unexpectedly high demand for flu shots late into the winter, and at times supplies were tight. The CDC said there are ample doses of flu shots to handle strong demand this year, and it strongly urged vaccination for the elderly and young children who are most vulnerable to influenza.