Every year, we line up for flu shots hoping that the annual vaccine will be the right formula to ward off that year's strain. It's filled with bits of neutralized flu virus that trigger your immune system to create antibodies that will destroy the active virus if and when it enters your body. Some years the vaccine is more effective than others, but each year scientists have to redesign it.

That's why researchers are hoping to create a universal flu vaccine that would be effective against every strain of the flu and wouldn't have to be modified every year. And llamas could play a significant role in reaching that goal.

Researchers have created a nasal spray derived from several llama antibodies that target many strains of the flu at once. A new study found that these antibodies were able to protect mice from various flu strains. The llama-derived antibodies can also survive without refrigeration for longer periods of time, which eventually could make flu treatment less expensive.

"[Our approach] could potentially be used as a preventive treatment from year to year and protect against both seasonal flu as well as potential pandemics, such as bird flu," Ian Wilson, a biochemist from Scripps Research who co-led the project, told PBS. The results of the study were published in the journal Science.

It will be a few more flu seasons (and require a lot more testing) before this spray will likely make it to human trials. But researchers who have been working unsuccessfully to create a universal vaccine say this one could work, says Science magazine. It particularly could be beneficial for older people, who are often hit hardest by the flu and don't get the best protection from annual vaccines. And because it wouldn't have to be reformulated each year, it could be made in bulk and stored in case of a flu pandemic.

Immunologist Antonio Lanzavecchia, a leading flu vaccine researcher at the Institute for Research in Biomedicine in Bellinzona, Switzerland, tells Science: "This is a great story and shows the power of antibody engineering."

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

Llamas could one day help prevent the flu
Llamas have special antibodies that could be the key to a true universal flu vaccine.