An inhaled Covid vaccine booster was more than 5-fold effective for inducing neutralizing antibodies at 28-days, and more durable at 1-year, than shots, vs Omicron BA.5 in a randomized trial https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(23)00350-X/fulltext @TheLancetInfDis
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