Researchers have genetically engineered a vaccine that can completely protect against multiple influenza viruses. Results of their study are published in the May 29, 2013 issue of Science Translational Medicine.
In Connecticut, a total of 9,430 positive influenza cases were documented for the current 2012–2013 flu season. Influenza activity varies from season to season. One reason for this variation is that the predominant subtype of circulating flu virus changes. In Connecticut, the predominant subtype for the majority of the 2013–2013 flu season was influenza A (H3N2).
Current seasonal flu vaccines are produced using chicken eggs. These vaccines take months to produce and are only marginally effective against the strains of influenza that are predicted to circulate that year.
This new engineered flu vaccine may be the proto-type to a universal flu vaccine effective against all flu strains. What makes this new vaccine different from previous flu vaccines is the delivery method.
The researchers used a de-activated vector (a de-activated adeno-associated virus already safely used in humans) to deliver antibodies to the site of initial infection. For respiratory viruses such as influenza, the initial infection site is the nasopharyngeal mucosa – namely the inner lining of the nasal cavity. The antibody they used was a modified version of a broadly neutralizing antibody to influenza discovered 2 years ago. This modified antibody targets a protein found on the surface of all 16 subtypes of the most dangerous influenza viruses. The researchers demonstrated that delivery of the antibodies via the nasal mucosa gave complete protection against 3 types of H5N1 and 2 types of H1N1, all of which have been associated with historic human pandemics (including the H1N1 that caused the influenza pandemic of 1918 that killed an estimated 50 million people worldwide).
“This is one of those stay-tuned efforts that surely could be very important,” said Michael Osterholm, an internationally known bio-security expert at the University of Minnesota.
These studies were performed in animals (mice and ferrets). Further studies are needed to determine their efficacy and safety in humans. In light of the recent outbreak of a new bird flu strain in China, a universal flu vaccine would certainly be handy.
Enjoy this article? Receive e-mail alerts when new articles by the Health Examiner become available. Just click on “Subscribe” at the top or bottom of the page. It’s anonymous and completely free.