LOS ANGELES - COVID-19 vaccine booster shots may be necessary every nine to 12 months, according to Dr. Stephen Hoge — the president of vaccine manufacturer Moderna."That probably looks like boosting on a nine to 12 month after primary series as an annual booster for now, at least while we’re continuing to see the evolution of the virus," Hoge said during an earnings call Thursday.Hoge noted that Moderna does not believe the virus is going to follow one path of evolution, so the best way to ensure protection "against the broadest number of variants of concern is a multivalent vaccine." Moderna is still waiting to receive complete data, Hoge said.Stéphane Bancel, the company’s chief executive officer, also discussed the importance of.