COVID-19 Vaccine Effectiveness Study Finally Published
A study examining the effectiveness of COVID-19 vaccines has been published after initially being blocked from a government health journal. According to the research, the vaccine is approximately 55% effective in preventing hospitalizations related to COVID-19 and has cut down emergency room visits and urgent care clinic trips by about 50%, as reported in a paper released Tuesday by JAMA Network Open.
While these findings align with prior research demonstrating the efficacy of COVID-19 vaccines, the study gained attention due to political appointees during the Trump administration deciding not to publish it in a CDC outlet. They expressed concerns that the study design could lead to flawed results due to potential false assumptions. However, many experts in public health argue that the design, which has been utilized for decades, offers a reliable way to gauge current vaccine effectiveness.
In a commentary that accompanied the study, Natalie Dean, a biostatistics expert at Emory University, emphasized the importance of regularly assessing vaccine effectiveness in response to changing immunity and evolving viral strains.
This research was initially intended for publication in the CDC’s Morbidity and Mortality Weekly Report this spring. After gaining clearance from the agency’s Office of Science, it faced scrutiny from acting CDC Director Jay Bhattacharya. Althea Grant-Lenzy, the CDC’s chief science officer, noted that while his decision delayed publication, it didn’t prevent it entirely—the authors were able to submit the study to external journals.
The study utilized a “test-negative design,” which involves analyzing patients admitted to hospitals or emergency rooms due to respiratory illnesses, checking vaccination status, and comparing the likelihood of a positive COVID-19 test between vaccinated and unvaccinated individuals.
Similar studies using this methodology have appeared in reputable journals like Pediatrics and the New England Journal of Medicine after expert review. Bhattacharya has questioned the validity of this methodology, suggesting that it may produce results influenced by external factors such as prior infections and differences in patient behavior.
Supporters of the study point out that the design is adept at adjusting for variations among those seeking medical care. They argue that most Americans have experienced COVID-19, which mitigates concerns about prior infections muddying the results. While every study design has its flaws, there seems to be a lack of practical alternatives suggested by officials to accurately measure current vaccine effectiveness.
This month, the CDC hosted a forum discussing the benefits and drawbacks of such studies. A panel that included Dean and others mainly championed the strengths of the methodology. Yet, it also featured a critic: Martin Kulldorff, a biostatistician with previous ties to figures advocating against pandemic shutdowns. He cautioned against including patients with varying health conditions in these studies and questioned the absence of longer-term evaluations of vaccine effectiveness.
“We were in a pandemic! That’s why!” a voice from the audience responded, highlighting the urgency of the situation.
