PMC:7519301 / 164-260 JSONTXT

{"project":"LitCovid-PD-CLO","denotations":[{"id":"T3","span":{"begin":37,"end":38},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T4","span":{"begin":74,"end":79},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T5","span":{"begin":94,"end":95},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"}],"text":"s questions about the possibility of a universally effective vaccine. The virus can mutate in a "}