Flu vaccine effective in 56 percent of cases

This season's flu vaccine was effective in only 56 percent of people who received the shot and completely failed in protecting the elderly against one of the strains, according to a recent analysis.

The U.S. Centers for Disease Control and Prevention found that the vaccine reduced the risk of medical visits caused by influenza A or influenza B by 56 percent. The vaccine protected 67 percent of people who were vaccinated against influenza B and only 47 percent of people against H3N2 influenza A, Reuters reports.

The vaccine protected only nine percent of people aged 65 and older against H3N2 influenza A.

The CDC said that the findings demonstrate the need for more effective weapons against influenza, which kills between 3,000 and 50,000 people annually in the U.S.

"We simply need a better vaccine against influenza, one that works better and lasts longer," Thomas Frieden, the CDC's director, said, according to Reuters.

Frieden said that while the findings are discouraging, people should continue to get vaccinations against the flu.

"(The findings) should not discourage future vaccination by persons aged 65 years (or older), who are at greater risk for more severe cases and complications from influenza," Frieden said, according to Reuters. "Although it's far from perfect, flu vaccination is by far the best tool we have to protect from flu."

Experts predict that pharmaceutical companies will be able to develop a universal flu vaccine to protect against all strains of flu within eight to 10 years, Reuters reports.