{"doi":"10.1016/j.ijid.2022.04.007","title":"Effect of a two-dose vs three-dose vaccine strategy in residential colleges using an empirical proximity network","abstract":"When SARS-CoV-2 escalated to a pandemic in early 2020, universities and colleges were forced to pivot to virtual instruction. As of fall 2021, many institutions of higher education had reopened, adopting and often mandating mitigation measures like indoor masking, social distancing, regular testing, and vaccination. However, the emergence of the Omicron B.1.1.529 variant in November 2021 disrupted this new routine. The Omicron variant has been shown to be highly transmissible, with researchers estimating the effective reproduction number of Omicron as 3.19 times higher than that of the Delta strain (Ito, Piantham, Nishiura, 2021Ito K. Piantham C. Nishiura H. Relative instantaneous reproduction number of omicron SARS-CoV-2 variant with respect to the Delta variant in Denmark.Journal of Medical Virology. 2021; Google Scholar). Furthermore, due to immune evasion, SARS-CoV-2 vaccines have reduced effectiveness against Omicron relative to previous variants (Cele, Jackson, Khoury, et al., 2021Cele S. Jackson L. Khoury D.S. et al.SARS-CoV-2 omicron has extensive but incomplete escape of pfizerBNT162b2 elicited neutralization and requires ACE2 for infection.MedRxiv. 2021; Google Scholar). Given the continued societal and educational interest in keeping college campuses open, we reran the models in our recent paper, adjusting parameter values to reflect the current COVID-19 situation (Hambridge, Kahn, Onnela, 2021Hambridge H.L. Kahn R. Onnela J.P. Examining SARS-CoV-2 interventions in residential colleges using an empirical network.International Journal of Infectious Diseases. 2021; 113: 325-330Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar). In brief, we modeled the spread of SARS-CoV-2 over an empirical contact network of students on a college campus taken from the Copenhagen Network Study (Sapiezynski, Stopczynski, Lassen, Lehmann, 2019Sapiezynski P. Stopczynski A. Lassen D.D. Lehmann S. Interaction data from the copenhagen networks study.Scientific Data. 2019; 6: 1-10Crossref PubMed Scopus (46) Google Scholar). The Copenhagen Network Study enrolled 706 students from the Technical University of Denmark and issued each student a smartphone configured to be Bluetooth discoverable at all times. We used a modified individual-level stochastic susceptible-exposed-infectious-recovered (SEIR) model to simulate disease spread over the course of a 16-week semester. To reflect the increased transmissibility of the Omicron variant, we increased the probability of transmission per 5 min interaction, roughly corresponding to a basic reproduction number of R0≈6.0. Based on updated research, we also adjusted the recovery rate, leading to an average infectious period of 10 days for both symptomatic and asymptomatic cases (Hay, Kissler, Fauver, et al., 2022Hay J.A. Kissler S.M. Fauver J.R. et al.Viral dynamics and duration of PCR positivity of the SARS-CoV-2 omicron variant.medRxiv. 2022; PubMed Google Scholar). Additionally, in order to align with the latest U.S. Centers for Disease Control and Prevention (CDC) guidelines, we shortened the student isolation period to 5 days (Centers for Disease Control and PreventionCenters for Disease Control and Prevention. Guidance for institutions of higher education (IHEs). 2022. https://www.cdc.gov/coronavirus/2019-ncov/community/colleges-universities/considerations.html. Accessed: 2022-02-19.Google Scholar). Given Omicron’s considerable escape from vaccine elicited immunity, we modified our model to use the proportion effectively immune. We explored population vaccine adoption rates of 40%, 60%, 80%, and 90%. Since many schools have already mandated vaccination, we were particularly interested in how a third booster dose would affect spread on college campuses. As such, we ran models with both two and three dose vaccination, assuming a vaccine efficacy of 30% for 2 doses and 70% for 3 doses (UK Health Security Agency, 2021UK Health Security Agency SARS-CoV-2 variants of concern and variants","journal":"International Journal of Infectious Diseases","year":2022,"id":295111,"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":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9497,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":109901,"name":"Rebecca Kahn","orcid":"0000-0001-9511-6142","position":1,"is_corresponding":false},{"id":305790,"name":"Jukka‐Pekka Onnela","orcid":"0000-0001-6613-8668","position":2,"is_corresponding":false},{"id":749881,"name":"Hali L. Hambridge","orcid":"0000-0002-4959-2815","position":0,"is_corresponding":true}],"reference_count":6,"raw_metadata":null,"created_at":"2026-07-19T00:31:05.260069Z","pmid":"35405350","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":[]}