Available data indicate that the uptake of COVID-19–bivalent vaccines and the use of the oral medication nirmatrelvir-ritonavir (Paxlovid) are still relatively low in the United States, with previous studies reporting that only an estimated 28% of eligible individuals were prescribed nirmatrelvir-ritonavir.

In a recent publication in the journal Open Forum Infectious Diseases, researchers conducted a modeling study to examine the public health impact of improving acceptance of these interventions in key risk groups. The study authors indicated that these interventions could guide further public health resources and policy and determine what percentage of severe COVID-19 cases are avoidable with these interventions.

The authors wrote, “Two key medical interventions against severe COVID-19 are bivalent vaccines and use of oral antiviral medications during COVID-19 illness, most commonly nirmatrelvir-ritonavir. The goal of this study is to help prioritize public health efforts to increase uptake of these interventions in the highest-risk groups.”

The researchers employed person-level data from the California Department of Public Health on COVID-19 cases, hospitalizations, mortality rates, and vaccine administration from July 23, 2022, to January 23, 2023. They also employed a quasi-Poisson regression model calibrated to recent historical data to predict future COVID-19 outcomes and modeled the impact of increasing uptake (up to 70% coverage) of bivalent COVID-19 vaccines and nirmatrelvir-ritonavir during acute illness in different risk groups.

The researchers indicated that risk groups were defined by age (≥50, ≥65, ≥75 years) and vaccination status (everyone, primary series only, previously vaccinated). The researchers also projected the number of deterred COVID-19 cases, hospitalizations, and deaths and the number needed to treat (NNT).

The results revealed, “The model predicted that increased uptake of bivalent COVID-19 boosters and nirmatrelvir-ritonavir (up to 70% coverage) in all eligible persons could avert an estimated 15.7% (95% uncertainty interval [UI], 11.2%-20.7%; NNT: 17,310) and 23.5% (95% UI, 13.1%-30.0%; NNT: 67) of total COVID-19-related deaths, respectively.”

The researchers also noted that in the high-risk group of individuals aged ≥65 years old alone, augmented uptake of bivalent boosters and nirmatrelvir-ritonavir could prevent an estimated 11.9% (95% UI, 8.4%-15.1%; NNT: 2,757) and 22.8% (95% UI, 12.7%-29.2%; NNT: 50) of total COVID-19-related deaths, respectively.

Based on their findings, the authors wrote, “In this study, our findings suggest that prioritizing uptake of bivalent vaccines and nirmatrelvir-ritonavir treatment among the oldest age groups would significantly and effectively reduce the number of severe COVID-19 infections in California but will not reduce the entire burden of severe COVID-19.”

The authors also noted that the findings from this study provide more confirmatory data on the public health benefit of employing both vaccination and the use of nirmatrelvir-ritonavir in the U.S. and emphasized the potential opportunities for policymakers to augment the uptake and availability of these life-saving interventions.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.