This Year's Flu Shot Didn't Do So Well

As the US flu season winds down, health officials say this year's vaccine didn't work very well: The shot had one of its worst effectiveness rates in the last two decades. A new strain that dominated the early winter was not well matched to the vaccine, leading to an intense early onslaught of flu, per the AP. This vaccine was around 25% to 30% effective in preventing adults from getting sick enough from the flu that they had to go to a doctor's office, clinic, or hospital, according to a CDC report this week. Children who were vaccinated were about 40% less likely to get treatment at a doctor's office or hospital.

"The winter respiratory virus season is slowly coming to a close, and we're all very grateful for that," said Dr. William Schaffner, a Vanderbilt University vaccine expert. Officials generally are pleased if a flu vaccine is 40% to 60% effective. Flu infections surged in late December and were especially intense in some parts of the country. New York City health officials called it the most intense season in 20 years. On the bright side, the flu is winding down: The number of states reporting high flu activity dropped to 16, many of them in a belt stretching from Colorado to Virginia.

CDC scientists estimate there have been at least 27 million illnesses, 350,000 hospitalizations, and 22,000 deaths from flu so far this season. At the same point last year, the estimates were at least 40 million illnesses, 520,000 hospitalizations, and about the same number of deaths. The flu vaccine may not protect everyone from getting sick, but it can prevent people from becoming severely ill and dying. That's why getting a flu shot remains worthwhile, Schaffner said.