{"doi":"10.7326/m20-7866","title":"Speed Versus Efficacy: Quantifying Potential Tradeoffs in COVID-19 Vaccine Deployment","abstract":"Letters5 January 2021Speed Versus Efficacy: Quantifying Potential Tradeoffs in COVID-19 Vaccine DeploymentFREECorrection(s) for this article:CorrectionsMay 2021Correction: Quantifying Potential Tradeoffs in COVID-19 Vaccine DeploymentFREEA. David Paltiel, PhD, Amy Zheng, BA, and Jason L. Schwartz, PhDA. David Paltiel, PhDYale School of Public Health, New Haven, Connecticut, Amy Zheng, BAHarvard Medical School, Boston, Massachusetts, and Jason L. Schwartz, PhDYale School of Public Health, New Haven, ConnecticutAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M20-7866 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Background: The global effort to develop a vaccine for coronavirus disease 2019 (COVID-19) has already produced 2 candidates, each requiring 2 doses, with reported efficacies exceeding 90% (1). The U.S. Food and Drug Administration (FDA) has granted Emergency Use Authorization for both vaccines (Pfizer-BioNTech and Moderna). Their reported efficacies greatly exceed the 50% threshold the FDA cited in a June 2020 guidance document (2). Additional vaccine candidates at earlier stages of development hold the promise of single dosing, simpler storage requirements, and more rapid immunity after vaccination (3).The availability of multiple vaccine options would be a welcome development but would create policy dilemmas. How do we define the \"best\" vaccine, and which populations should receive it? Should the FDA expect all candidates to meet or exceed the 90% efficacy benchmark established by the 2 frontrunners? From a population perspective, how good is \"good enough\"? Given that some portion of the population will inevitably fail to return for a second dose, might a single-dose vaccine that is 75% effective and takes 2 weeks to achieve protection better contain the pandemic than a 95%-effective vaccine requiring 2 doses and a 4-week lag before full efficacy?Objective: To quantify the speed-versus-efficacy tradeoff using a previously published model of a COVID-19 vaccination program (4). The model accounts for transmission of severe acute respiratory syndrome coronavirus 2, COVID-19 disease severity, and recovery or vaccination leading to protective immunity. Modifying parameters related to vaccine efficacy, vaccination program scale-up and coverage, and the time to vaccine benefits, we compared the likely performance of 1- and 2-dose vaccine candidates over a 6-month horizon on outcomes of cumulative infections, deaths, and peak hospitalizations.Methods and Findings: Consistent with the FDA efficacy definition, we assumed that a 2-dose vaccine produced a 95% decrease in rates of progression to symptomatic disease, to severe or critical disease from mild disease, and to COVID-19–related death, as well as a nearly 3-fold increase in rates of disease recovery. We further assumed that this vaccine had a 0.5% daily uptake, double the observed peak rate for influenza vaccination in the United States (4), and took 4 weeks to achieve lifetime protection, allowing for partial immunity after the first dose. We compared this vaccine with 2 hypothetical, single-dose alternatives, one conferring lifetime protection and the other with stable efficacy of uncertain duration (exponentially distributed with a mean duration of 6 months). Both of these single-dose vaccines were assumed to achieve more rapid daily uptake (0.75%) and to take effect 14 days after administration. We considered efficacies for both single-dose vaccines ranging from 0% to 100%.We did the base analysis in the context of an epidemic with an effective reproductive number (Rt) of 1.8. Other inputs were obtained from published sources, particularly the guidance for COVID-19 model parameterization from the Centers for Disease Control and Prevention and the Department of Health and Human Services Office of the Assistant Secretary for Preparedness and Response (4, 5).In ","journal":"Annals of Internal Medicine","year":2021,"id":153647,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":67,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9468,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":226456,"name":"Amy Zheng","orcid":"0009-0004-4051-2796","position":1,"is_corresponding":false},{"id":652538,"name":"Jason L. Schwartz","orcid":null,"position":2,"is_corresponding":false},{"id":226455,"name":"A. David Paltiel","orcid":"0000-0002-4861-3290","position":0,"is_corresponding":true}],"reference_count":1,"raw_metadata":null,"created_at":"2026-07-18T23:43:44.759273Z","pmid":"33395345","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}