A universal flu vaccine, with the ability to potentially protect from all influenza strains that have circulated over the years, will be available within the next five years, according to researchers.

Scientists from the National Institute of Allergy and Infectious Diseases (NIAID) discovered the first antibody that can fight and protect against all types of influenza A, which can lead to one universal vaccine replacing the yearly flu shots only capable of treating individual strains.

Research led by NIAID's Gary J. Nabel, M.D., Ph.D, experimented with mice, ferrets and monkeys using a two-step immunization approach to "elicit antibodies" that attacked a multitude of strains associated with influenza.

The findings showed antibodies produced with the ability to prevent all known strains of the influenza virus, including strains dating back from 1934 until the most recent emerged in 2006 and 2007, because of similar proteins found within all variations, according to Nabel.

In a related experiment, 80 percent of mice with "deadly levels of flu virus" survived after receiving the prime-boost vaccination. The prime-boost contains H1 subtypes of the influenza A virus along with antibodies generated from other influenza subtypes.

Scientists deducted from the experiment that this prime-boost shot could potentially protect against all or most subtypes of influenza A and possibly other infectious diseases.

"We are excited by these results," Dr. Nabel said in a press release. "The prime-boost approach opens a new door to vaccinations for influenza that would be similar to vaccination against such diseases as hepatitis, where we vaccinate early in life and then boost immunity through occasional, additional inoculations in adulthood."

Flu costs the lives of nearly 49,000 Americans each year, according to the Centers for Disease Control and Prevention (CDC), as a result of new viruses emerging almost yearly. The researchers report the universal virus used for most common strains of influenza could be available shortly after large-scale trials are tested and deemed effective.

"We may be able to begin efficacy trials of a broadly protective flu vaccine in three to five years," Dr. Nabel said.

Allergy Influenza A virus