title: Dengue-2 vaccine: virological, immunological, and clinical responses of six yellow fever-immune recipients.
abstract: Six male volunteers, previously immunized with yellow fever vaccine, were inoculated subcutaneously with a live, attenuated dengue-2 virus (PR-159/S-1) candidate vaccine. Five recipients developed viremia 8 or 9 days after vaccination, which lasted 1 to 10 days. The onset of viremia was followed by fever in three people, transient leukopenia in four, and an erythematous rash in one. One volunteer developed an oral temperature of 38.8 degrees C with headache, myalgia, fatigue, and photophobia suggestive of mild dengue fever. All five viremic volunteers developed fourfold or greater rises in serum neutralizing antibody. The sixth volunteer, who had a low titer of preexisting dengue-2 neutralizing antibody, had no viremia, no symptoms, and a modest rise in hemagglutination inhibiting antibody. Virus isolates obtained from plasma retained the small-plaque and temperature-sensitive growth characteristics of the vaccine virus in vitro. In this study, the vaccine virus genetically stable and immunogenic and seemed sufficiently attenuated for additional testing in humans.
mesh_terms: D000328:Adult; D000917:Antibody Formation; D003716:Dengue Virus / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014611:Vaccination; D014613:Vaccines, Attenuated / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology*; D015004:Yellow Fever / Q000276:immunology*
chemical_list: D014613:Vaccines, Attenuated; D014765:Viral Vaccines