Inhalation of the powerful synthetic protein can spark the body’s immune system into fighting an infection within just two hours, researchers found.
The study from San Diego State University suggests the treatment could be used to prevent someone infected with the flu virus from developing symptoms.
It could also fight a new strain of pandemic flu for which we have no vaccine, they said.
Lead author Joy Phillips PhD said: ‘The flu virus is very sneaky and actively keeps the immune system from detecting it for a few days until you are getting symptoms.’
The synthetic protein, EP67, is already used as an adjuvant for existing vaccines but researchers realised it could be used by itself to activate the innate immune system.
To test the theory, they infected mice with a flu virus and administered some of them with the EP67 protein. These mice lost around 6% of their weight – a marker for illness – compared with 20% among untreated mice.
Dr Phillips said: ‘Our research showed that by introducing EP67 into the body within 24 hours of exposure to the flu virus caused the immune system to react almost immediately to the threat, well before your body normally would.’
He added that current flu treatments target the virus directly and viruses may develop resistance. 'EP67 could potentially be a therapeutic that someone would take when they know they've been exposed that would help the body fight off the virus before you get sick.’