Patients who receive a COVID-19 booster shot after having completed the first one- or two-dose regimen of the vaccine have roughly 4 months before protection from that shot starts to wane, according to the latest information from the Centers for Disease Control and Prevention. The latest COVID-19 information from the Centers for Disease Control and Prevention. An Early Release article published by Morbidity and Mortality Weekly Report notes specifically that “Vaccine effectiveness (VE) against COVID-19–associated emergency department/urgent care (ED/UC) visits and hospitalizations was higher after the third dose than after the second dose, but waned with time since vaccination. During the Omicron-predominant period, VE against COVID-19–associated ED/UC visits and hospitalizations was 87% and 91%, respectively, during the 2 months after a third dose and decreased to 66% and 78% by the fourth month after a third dose.” Where that revelation may lead—such as investigation into the safety and efficacy of additional shots—remains to be seen.
CDC: Waning Immunity After a COVID-19 Booster Is Only a Matter of Months