COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact

Abstract Trial results for two COVID-19 vaccines suggest at least 90% efficacy against symptomatic disease (VEDIS). It remains unknown whether this efficacy is mediated by lowering SARS-CoV-2 infection susceptibility (VESUSC) or development of symptoms after infection (VESYMP). We aim to assess and...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: David A. Swan, Chloe Bracis, Holly Janes, Mia Moore, Laura Matrajt, Daniel B. Reeves, Eileen Burns, Deborah Donnell, Myron S. Cohen, Joshua T. Schiffer, Dobromir Dimitrov
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2021
Materias:
R
Q
Acceso en línea:https://doaj.org/article/2eab7a70fea74c65a94d95d63fb05ed5
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:doaj.org-article:2eab7a70fea74c65a94d95d63fb05ed5
record_format dspace
spelling oai:doaj.org-article:2eab7a70fea74c65a94d95d63fb05ed52021-12-02T16:24:59ZCOVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact10.1038/s41598-021-94719-y2045-2322https://doaj.org/article/2eab7a70fea74c65a94d95d63fb05ed52021-07-01T00:00:00Zhttps://doi.org/10.1038/s41598-021-94719-yhttps://doaj.org/toc/2045-2322Abstract Trial results for two COVID-19 vaccines suggest at least 90% efficacy against symptomatic disease (VEDIS). It remains unknown whether this efficacy is mediated by lowering SARS-CoV-2 infection susceptibility (VESUSC) or development of symptoms after infection (VESYMP). We aim to assess and compare the population impact of vaccines with different efficacy profiles (VESYMP and VESUSC) satisfying licensure criteria. We developed a mathematical model of SARS-CoV-2 transmission, calibrated to data from King County, Washington. Rollout scenarios starting December 2020 were simulated with combinations of VESUSC and VESYMP resulting in up to 100% VEDIS. We assumed no reduction of infectivity upon infection conditional on presence of symptoms. Proportions of cumulative infections, hospitalizations and deaths prevented over 1 year from vaccination start are reported. Rollouts of 1 M vaccinations (5000 daily) using vaccines with 50% VEDIS are projected to prevent 23–46% of infections and 31–46% of deaths over 1 year. In comparison, vaccines with 90% VEDIS are projected to prevent 37–64% of infections and 46–64% of deaths over 1 year. In both cases, there is a greater reduction if VEDIS is mediated mostly by VESUSC. The use of a “symptom reducing” vaccine will require twice as many people vaccinated than a “susceptibility reducing” vaccine with the same 90% VEDIS to prevent 50% of the infections and death over 1 year. Delaying the start of the vaccination by 3 months decreases the expected population impact by more than 50%. Vaccines which prevent COVID-19 disease but not SARS-CoV-2 infection, and thereby shift symptomatic infections to asymptomatic infections, will prevent fewer infections and require larger and faster vaccination rollouts to have population impact, compared to vaccines that reduce susceptibility to infection. If uncontrolled transmission across the U.S. continues, then expected vaccination in Spring 2021 will provide only limited benefit.David A. SwanChloe BracisHolly JanesMia MooreLaura MatrajtDaniel B. ReevesEileen BurnsDeborah DonnellMyron S. CohenJoshua T. SchifferDobromir DimitrovNature PortfolioarticleMedicineRScienceQENScientific Reports, Vol 11, Iss 1, Pp 1-9 (2021)
institution DOAJ
collection DOAJ
language EN
topic Medicine
R
Science
Q
spellingShingle Medicine
R
Science
Q
David A. Swan
Chloe Bracis
Holly Janes
Mia Moore
Laura Matrajt
Daniel B. Reeves
Eileen Burns
Deborah Donnell
Myron S. Cohen
Joshua T. Schiffer
Dobromir Dimitrov
COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
description Abstract Trial results for two COVID-19 vaccines suggest at least 90% efficacy against symptomatic disease (VEDIS). It remains unknown whether this efficacy is mediated by lowering SARS-CoV-2 infection susceptibility (VESUSC) or development of symptoms after infection (VESYMP). We aim to assess and compare the population impact of vaccines with different efficacy profiles (VESYMP and VESUSC) satisfying licensure criteria. We developed a mathematical model of SARS-CoV-2 transmission, calibrated to data from King County, Washington. Rollout scenarios starting December 2020 were simulated with combinations of VESUSC and VESYMP resulting in up to 100% VEDIS. We assumed no reduction of infectivity upon infection conditional on presence of symptoms. Proportions of cumulative infections, hospitalizations and deaths prevented over 1 year from vaccination start are reported. Rollouts of 1 M vaccinations (5000 daily) using vaccines with 50% VEDIS are projected to prevent 23–46% of infections and 31–46% of deaths over 1 year. In comparison, vaccines with 90% VEDIS are projected to prevent 37–64% of infections and 46–64% of deaths over 1 year. In both cases, there is a greater reduction if VEDIS is mediated mostly by VESUSC. The use of a “symptom reducing” vaccine will require twice as many people vaccinated than a “susceptibility reducing” vaccine with the same 90% VEDIS to prevent 50% of the infections and death over 1 year. Delaying the start of the vaccination by 3 months decreases the expected population impact by more than 50%. Vaccines which prevent COVID-19 disease but not SARS-CoV-2 infection, and thereby shift symptomatic infections to asymptomatic infections, will prevent fewer infections and require larger and faster vaccination rollouts to have population impact, compared to vaccines that reduce susceptibility to infection. If uncontrolled transmission across the U.S. continues, then expected vaccination in Spring 2021 will provide only limited benefit.
format article
author David A. Swan
Chloe Bracis
Holly Janes
Mia Moore
Laura Matrajt
Daniel B. Reeves
Eileen Burns
Deborah Donnell
Myron S. Cohen
Joshua T. Schiffer
Dobromir Dimitrov
author_facet David A. Swan
Chloe Bracis
Holly Janes
Mia Moore
Laura Matrajt
Daniel B. Reeves
Eileen Burns
Deborah Donnell
Myron S. Cohen
Joshua T. Schiffer
Dobromir Dimitrov
author_sort David A. Swan
title COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
title_short COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
title_full COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
title_fullStr COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
title_full_unstemmed COVID-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
title_sort covid-19 vaccines that reduce symptoms but do not block infection need higher coverage and faster rollout to achieve population impact
publisher Nature Portfolio
publishDate 2021
url https://doaj.org/article/2eab7a70fea74c65a94d95d63fb05ed5
work_keys_str_mv AT davidaswan covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT chloebracis covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT hollyjanes covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT miamoore covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT lauramatrajt covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT danielbreeves covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT eileenburns covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT deborahdonnell covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT myronscohen covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT joshuatschiffer covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
AT dobromirdimitrov covid19vaccinesthatreducesymptomsbutdonotblockinfectionneedhighercoverageandfasterrollouttoachievepopulationimpact
_version_ 1718384041927901184