Vaccines against the pandemic H1N1 influenza strain of 2009 also generated immunity to other diverse flu viruses.

A team including Rafi Ahmed at Emory University in Atlanta, Georgia, and Patrick Wilson at the University of Chicago in Illinois previously showed that people infected with pandemic H1N1 flu made antibodies that neutralized both H1N1 and other flu strains. Now the researchers have analysed immune cells from 24 people who received an H1N1 vaccine, and found that these cells also produce these broadly neutralizing antibodies. The antibodies recognize conserved molecular features of both seasonal and pandemic flu strains — including the strain responsible for the 1918 pandemic.

The findings could aid the design of flu vaccines that recognize all flu viruses.

Proc. Natl Acad. Sci. USA http://dx.doi.org/10.1073/pnas.1118979109 (2012)