New data released by the Centers for Disease Control and Prevention show that many older adults become sick with the flu despite being vaccinated.
The CDC data looked at outpatient clinic visits and found that the flu vaccine was only 9 percent effective in people 65 and older who came down with the A strain of the virus, which is also known as H3N2. That strain has caused hundreds of hospitalizations in Minnesota this season.
Minnesota Department of Health epidemiologist Dr. Ruth Lynfield said the data show there's room for improvement.
"It's important that people work on better vaccines, particularly for those people who are at highest risk for severe influenza so that they can be protected better," Lynfield said.
Lynfield said the study doesn't change the agency's recommendation that people get vaccinated.
"We don't have the data on how many hospitalizations vaccination prevents, so it could well be the case that someone who's 65 and older gets vaccinated, they get ill, but perhaps the vaccine prevented them from having an extremely severe illness," Lynfield said.
FLU ACTIVITY DECLINING
The Health Department released new data showing flu activity continues to slow in the state. Officials have confirmed 12 more flu deaths, bringing the total for the season to 148. Most of the deaths have been in older people.
Hospitalizations due to flu also continue to decline in Minnesota. Health officials say 59 people were hospitalized with laboratory-confirmed influenza last week, compared with 72 the week before. So far this season, Minnesota has seen 2,784 hospitalizations.
Five nursing homes reported confirmed outbreaks of flu last week while nine schools reported outbreaks of flu-like illness.
The Associated Press contributed to this report.