The study found that during the first six months following the final shot, there was “substantial” and “durable” protection against dying or needing a ventilator.
The original COVID-19 vaccines provided appreciable levels of protection against the worst disease outcomes more than a year after the final dose, according to a study released on Thursday by the Centers for Disease Control and Prevention.
The study found that during the first six months following the final shot, there was “substantial” and “durable” protection against dying or needing a ventilator. The highest level of protection at any time was reached at 76%.
The study found that the shots continued to provide “clinically meaningful levels of protection” even more than a year later.
Over a year later, it was still only about 56% effective in preventing death and ventilation. The study’s authors noted that the results “demonstrate clinically meaningful levels of protection for approximately one year” but “suggest some waning of protection against [invasive mechanical ventilation] and death after six months from receipt of the last dose.”
Adults who received two or more of the original shot doses between February 2022 and the end of January 2023 were the focus of the study.
Previous infections were not taken into account in the study. The study made the interesting discovery that “protection against these critical outcomes appeared to correlate more closely with time since last dose than with total number of doses received.”
After federal agencies last week agreed to switch all doses over to the bivalent vaccine, which targets the original coronavirus strain as well as subvariants of omicron, the original COVID-19 shot is no longer available in the United States.
Peter Marks, the FDA’s top vaccine official, stated in a statement that “at this stage of the pandemic, data support simplifying the use of the authorised mRNA bivalent COVID-19 vaccines, and the agency believes that this approach will help encourage future vaccination.”
Instead of receiving multiple doses of the original shot of COVID 19 vaccines, the majority of unvaccinated Americans will now only receive one updated bivalent shot. The federal agencies last week also approved another updated COVID-19 booster shot for some Americans this spring, including those over 65 and some people with compromised immune systems.
To get the nation ready for a potential winter wave of coronavirus, federal officials are considering a fall booster campaign for the rest of the nation.
The results of the study, specifically that the vaccinations are most effective within six months of administration, “should be taken into account along with trends in COVID-19 incidence and risk factors for severe disease when planning COVID-19 revaccination schedules,” the study’s authors suggested.