Enlarge / A tray of prepared syringes for booster vaccinations with Moderna's vaccine. (credit: Getty | Picture alliance) Amid the stratospheric rise of the omicron variant, real-world data on the effectiveness of COVID-19 booster doses is now rolling in—and it is only looking up for boosters. The Centers for Disease Control and Prevention reported three studies Friday, two published in the CDC's Morbidity and Mortality Weekly Report (MMWR) and another, appearing in JAMA, by CDC scientists. One of the MMWR studies looked at the vaccination status of nearly 10 million COVID-19 cases from 25 state and local health departments.