Cecilia DowdFeb 12, 2018, 10:56 pmFeb 13, 2018, 11:42 am

The flu shot is less effective this year; researchers say eggs are to blame

Making vaccines isn’t a perfect science


GARDEN CITY — Thousands of people die from influenza every year in the United States. This year, the nation is facing the worst flu season seen in years, armed with a vaccine that isn't as effective as it could be.

“Some years the vaccine is more effective than others, and unfortunately, this year the vaccine has not been optimally effective,” said Dr. K.C. Rondello, clinical associate professor of public health at Adelphi University.

Dr. Rondello says vaccine efficacy usually tops out at around 65 percent, but this year it is only about 10 to 30 percent effective. But he says the dismal numbers are not a reason to skip getting a flu shot since it still can help in case you come down with the illness.

“The vaccine may mitigate your symptoms so the symptoms aren't as severe, and it may lessen the duration of illness so that you'll recover faster,” he said.

Researchers make new vaccines each year to combat different flu strains, but that requires a bit of guesswork, according to Dr. Rondello.

“Each year the vaccine is developed, consists of epidemiologists' best guess as to the flu strains that will be most predominant in the coming flu season,” Dr. Rondello said.

So what went wrong this year? First, it was the H3N2 strain which has been historically proven to be tricky.

“It is mostly resistant to vaccines and has been very virulent,” he explained.

And then there's the issue with the vaccine resulting from its egg base.

“That's one of the reasons why the vaccine isn't as effective as we hoped,” he said. “This year, when the vaccine was being cultivated in eggs, there was a mutation and that led to the vaccine being less effective than optimal."

Even still, Dr. Rondello says the most important thing to know about vaccines is that it doesn't have the power to make people sick.

“When it comes to a flu shot injected with a needle, that vaccine is a killed vaccine. There is no way to get influences from a killed vaccine,” he said.

What's On Now & Next



Oyster Bay, New York
Broken Clouds