Delta variant is so contagious it 'raises the bar' for Covid vaccines, Moderna president saysCNBC • 09/16/21
Moderna says a study showed falling COVID-19 immunity over time and a need for boosters - even though most 'breakthrough' infections weren't severeBusiness Insider • 09/16/21
Moderna Vaccine Highly Effective Against Delta—But Protection Against Infection Wanes Over Time, New Data SuggestsForbes • 09/15/21
Moderna releases new data on Covid breakthrough cases it says supports need for booster shotsCNBC • 09/15/21