US researchers found that the treatment boosted the immune system and prevented death despite “lethal” doses of flu being first administered to the mice.
Their findings, published in the American Journal of Respiratory and Critical Care Medicine, indicate that the nasal aerosol treatment has “great potential”.
Meanwhile, a British flu expert has said that the work could be useful for influencing other research even if it is not directly transferable.
Every year there are three to five million cases of flu across the globe, with 250,000 to 500,000 deaths, according to the World Health Organisation (WHO).
There are annual vaccinations brought out to combat flu, but scientists say they are “variably effective”, mainly because of the way viruses evolve.
During the study they examined how effective the protein granulocyte macrophage-colony stimulating factor (GM-CSF) was for combating the symptoms.
The protein was known to increase the activity of alveolar macrophages (AM), which is the first defence against inhaled organisms and molecules.
Mice were infected with a lethal dose of a flu virus and some were given GM-CSF and others were not.
Researchers found that the untreated mice lost weight and died within days while those treated survived. It was also noted that although the treated mice lost weight initially they soon regained it again.
A number of different flu strains were used in the study, including swine flu (H1N1).
Copyright © Press Association 2011