{"doi":"10.1101/2022.04.28.22274446","title":"Vaccine Stockpile Sharing For Selfish Objectives","abstract":"Abstract The COVAX program aims to provide global equitable access to life-saving vaccines. However, vaccine protectionism by wealthy nations has limited progress towards vaccine sharing goals. For example, as of April 2022 only ∼ 20% of the population in Africa has received at least one COVID-19 vaccine dose. Here we use a two-nation coupled epidemic model to evaluate optimal vaccine-sharing policies given a selfish objective: in which countries with vaccine stockpiles aim to minimize fatalities in their own populations. Despite the selfish objective, we find it is often optimal for a donor nation to share a significant fraction of its vaccine stockpile. Mechanistically, sharing a vaccine stockpile reduces the intensity of outbreaks in the recipient nation, in turn reducing travel-associated incidence in the donor nation. This effect is intensified as vaccination rates decrease and epidemic coupling increases. Despite acting selfishly, vaccine sharing by a donor nation significantly reduces transmission and fatalities in the recipient nation. Moreover, we find that there are hybrid sharing policies that have a negligible effect on fatalities in the donor nation compared to the optimal policy while significantly reducing fatalities in the recipient nation. Altogether, these findings provide a rationale for nations with extensive vaccine stockpiles to share with other nations.","journal":"medRxiv","year":2022,"id":308017,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9547,"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":237882,"name":"Joshua S. Weitz","orcid":"0000-0002-3433-8312","position":1,"is_corresponding":false},{"id":393338,"name":"Y. Wardi","orcid":"0000-0001-5293-0478","position":2,"is_corresponding":false},{"id":237893,"name":"Shashwat Shivam","orcid":"0000-0003-4610-4190","position":0,"is_corresponding":true}],"reference_count":17,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T00:33:00.101913Z","pmid":null,"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":[]}