With H3N2 the predominant strain, Siegel expects to see more elderly patients than last year -- and more deaths. H3N2 tends to cause more pneumonia and other complications than other forms of flu, he added.
"Last year, there were 10,000 deaths compared to the normal 34,000," he said. "The age distribution of deaths this year will be back to the elderly."
In Europe, the H1N1 strain is the predominant strain, Siegel noted.
"So much of the U.S. population was vaccinated against H1N1 last year and so much immunity developed as the thing spread like wildfire, that's the reason the predominate strain is H3N2 -- it's all about immunity," he said.
Siegel thinks everyone should get vaccinated and it's not too late to do so.
"There is plenty of time to take it," he stressed. "Now is the time to take it, because it becomes effective in about two or three weeks, and you will have stronger immunity than if you took it back in August."
For more information on flu, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Marc Siegel, M.D., associate professor, medicine, New York University, New York City; Tom Skinner, spokesman, U.S. Centers for Disease Control and Prevention
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