I'm guessing the headline came from this snippet: > When the researchers tested this strategy with a mouse virus called Nodamura, they did it with mutant mice

I'm guessing the headline came from this snippet: > When the researchers tested this strategy with a mouse virus called Nodamura, they did it with mutant mice lacking T and B cells. With one vaccine injection, they found the mice were protected from a lethal dose of the unmodified virus for at least 90 days. Note that some studies show nine mouse days are roughly equivalent to one human year. So assuming you can extrapolate to human timescales, it would be booster every 10 years. I also doubt it will be effective that long. Would have been nice for them to mention how long normal vaccines remain effective in mice.