The effectiveness of the current season's influenza vaccine is about 45 percent, according to a new CDC report.
The research team used the U.S. Influenza Vaccine Effectiveness Network to examine data for 4,112 children and adults with acute respiratory illness from Oct. 23, 2019, to Jan. 25.
They estimated that the current flu vaccine's effectiveness against both types of flu was 45 percent. They also estimated that the vaccine's effectiveness in preventing the B/Victoria strain was 50 percent and in preventing A(H1N1)pdm09 was 37 percent.
The vaccine's effectiveness was higher among children and adolescents who are 6 months to 17 years old, than among adults.
"Vaccine effectiveness estimates are consistent with those from previous seasons," researchers wrote.
The CDC estimates flu has caused 26 million illnesses, 250,000 hospitalizations and 14,000 deaths this season.