The title of the post is a copy and paste from the first two paragraphs of the linked academic press release here:
A universal flu vaccine that could prevent a potential influenza pandemic has been a holy grail for epidemiologists around the world ever since the first flu vaccines were developed in 1938.
Now, an international team of researchers from the University of Michigan, the Icahn School of Medicine at Mount Sinai and other institutions believe they could bring the scientific community a step closer to developing one after proving that targeting a specific area of the flu virus does protect humans.
Novel correlates of protection against pandemic H1N1 influenza A virus infection
Sophia Ng, Raffael Nachbagauer, […]Aubree Gordon
Nature Medicine (2019)
Influenza viruses remain a severe threat to human health, causing up to 650,000 deaths annually1,2. Seasonal influenza virus vaccines can prevent infection, but are rendered ineffective by antigenic drift. To provide improved protection from infection, novel influenza virus vaccines that target the conserved epitopes of influenza viruses, specifically those in the hemagglutinin stalk and neuraminidase, are currently being developed3. Antibodies against the hemagglutinin stalk confer protection in animal studies4,5,6. However, no data exist on natural infections in humans, and these antibodies do not show activity in the hemagglutination inhibition assay, the hemagglutination inhibition titer being the current correlate of protection against influenza virus infection7,8,9. While previous studies have investigated the protective effect of cellular immune responses and neuraminidase-inhibiting antibodies, additional serological correlates of protection from infection could aid the development of broadly protective or universal influenza virus vaccines10,11,12,13. To address this gap, we performed a household transmission study to identify alternative correlates of protection from infection and disease in naturally exposed individuals. Using this study, we determined 50% protective titers and levels for hemagglutination inhibition, full-length hemagglutinin, neuraminidase and hemagglutinin stalk-specific antibodies. Further, we found that hemagglutinin stalk antibodies independently correlated with protection from influenza virus infection.