Skip to main content


Borchering, Rebecca K.; Mullany, Luke C.; Howerton, Emily; Chinazzi, Matteo; Smith, Claire P.; Qin, Michelle; Reich, Nicholas G.; Contamin, Lucie; Levander, John; & Kerr, Jessica, et al. (Preprint). Impact of SARS-CoV-2 Vaccination of Children Ages 5-11 Years on COVID-19 Disease Burden and Resilience to New Variants in the United States, November 2021-March 2022: A Multi-Model Study. medRxiv. PMCID: PMC8936106


BACKGROUND: SARS-CoV-2 vaccination of persons aged 12 years and older has reduced disease burden in the United States. The COVID-19 Scenario Modeling Hub convened multiple modeling teams in September 2021 to project the impact of expanding vaccine administration to children 5-11 years old on anticipated COVID-19 burden and resilience against variant strains.
METHODS: Nine modeling teams contributed state- and national-level projections for weekly counts of cases, hospitalizations, and deaths in the United States for the period September 12, 2021 to March 12, 2022. Four scenarios covered all combinations of: 1) presence vs. absence of vaccination of children ages 5-11 years starting on November 1, 2021; and 2) continued dominance of the Delta variant vs. emergence of a hypothetical more transmissible variant on November 15, 2021. Individual team projections were combined using linear pooling. The effect of childhood vaccination on overall and age-specific outcomes was estimated by meta-analysis approaches.
FINDINGS: Absent a new variant, COVID-19 cases, hospitalizations, and deaths among all ages were projected to decrease nationally through mid-March 2022. Under a set of specific assumptions, models projected that vaccination of children 5-11 years old was associated with reductions in all-age cumulative cases (7.2%, mean incidence ratio [IR] 0.928, 95% confidence interval [CI] 0.880-0.977), hospitalizations (8.7%, mean IR 0.913, 95% CI 0.834-0.992), and deaths (9.2%, mean IR 0.908, 95% CI 0.797-1.020) compared with scenarios where children were not vaccinated. This projected effect of vaccinating children 5-11 years old increased in the presence of a more transmissible variant, assuming no change in vaccine effectiveness by variant. Larger relative reductions in cumulative cases, hospitalizations, and deaths were observed for children than for the entire U.S. population. Substantial state-level variation was projected in epidemic trajectories, vaccine benefits, and variant impacts.
CONCLUSIONS: Results from this multi-model aggregation study suggest that, under a specific set of scenario assumptions, expanding vaccination to children 5-11 years old would provide measurable direct benefits to this age group and indirect benefits to the all-age U.S. population, including resilience to more transmissible variants.


Reference Type

Journal Article

Year Published


Journal Title



Borchering, Rebecca K.
Mullany, Luke C.
Howerton, Emily
Chinazzi, Matteo
Smith, Claire P.
Qin, Michelle
Reich, Nicholas G.
Contamin, Lucie
Levander, John
Kerr, Jessica
Espino, J.
Hochheiser, Harry
Lovett, Kaitlin
Kinsey, Matt
Tallaksen, Kate
Wilson, Shelby
Shin, Lauren
Lemaitre, Joseph C.
Hulse, Juan D.
Kaminsky, Joshua
Lee, Elizabeth C.
Davis, Jessica T.
Mu, Kunpeng
Xiong, Xinyue
Piontti, Ana Pastore Y.
Vespignani, Alessandro
Srivastava, Ajitesh
Porebski, Przemyslaw
Venkatramanan, Srini
Adiga, Aniruddha
Lewis, Bryan
Klahn, Brian
Outten, Joseph
Hurt, Benjamin
Chen, Jiangzhuo
Mortveit, Henning
Wilson, Amanda
Marathe, Madhav
Hoops, Stefan
Bhattacharya, Parantapa
Machi, Dustin
Chen, Shi
Paul, Rajib
Janies, Daniel
Thill, Jean-Claude
Galanti, Marta
Yamana, Teresa
Pei, Sen
Shaman, Jeffrey
Espana, Guido
Cavany, Sean
Moore, Sean M.
Perkins, Alex
Healy, Jessica M.
Slayton, Rachel B.
Johansson, Michael A.
Biggerstaff, Matthew
Shea, Katriona
Truelove, Shaun A.
Runge, Michael C.
Viboud, C├ęcile
Lessler, Justin

Article Type




Data Set/Study

COVID-19 Scenario Modeling Hub


United States of America




Lessler - 0000-0002-9741-8109