Universal flu vaccine could head off future pandemics

Progress is being reported on a universal flu vaccine – one that works against all current subtypes and future viruses.¹

The new multivalent mRNA vaccine encoded hemagglutinins (HA), one of two major surface proteins of flu, from all known A and B influenza subtypes. When they injected two doses into mice and ferrets, the animals generated high levels of antibodies against all 20 of the HA antigens. ‘The levels were tens- to hundreds-of-fold higher than what you need for protection,’ says Drew Weissman from the University of Pennsylvania.

What also pleased the team was the strong antibody response against each of the antigens. ‘With multivalent vaccines, there’s often some sort of predominance, but that wasn’t seen here,’ says virologist Seema Lakdawala at Emory University, who led the ferret experiments. For example, a dengue vaccine usually only elicits an adequate antibody response against two of the four types.