title: Yellow-fever before smallpox vaccination.
mesh_terms: D004336:Drug Antagonism; D006801:Humans; D012900:Smallpox Vaccine; D013997:Time Factors; D014611:Vaccination; D014765:Viral Vaccines; D015004:Yellow Fever / Q000517:prevention & control*
chemical_list: D012900:Smallpox Vaccine; D014765:Viral Vaccines