摘要：ObjectiveTo compare the reactogenicity of three yellow fever (YF) vaccines from WHO-17Dand Brazilian 17DD substrains (different seed-lots) and placebo.MethodsThe study involved 1,087 adults eligible for YF vaccine in Rio de Janeiro, Brazil.Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) wereadministered (“day 0”) following standardized procedures adapted to allow blindingand blocked randomization of participants to coded vaccine types. Adverse eventsafter immunization were ascertained in an interview and in diary forms filled in byeach participant. Liver enzymes were measured on days 0, 4-20 and 30 of the study.Viremia levels were measured on days 4 to 20 of follow-up. The immune responsewas verified through serologic tests.ResultsParticipants were mostly young males. The seroconversion rate was above 98%among those seronegative before immunization. Compared to placebo, the excess riskof any local adverse events ranged from 0.9% to 2.5%, whereas for any systemicadverse events it ranged from 3.5% to 7.4% across vaccine groups. The excess risk ofevents leading to search for medical care or to interruption of work activities rangedfrom 2% to 4.5%. Viremia was detected in 3%-6% of vaccinees up to 10 days aftervaccination. Variations in liver enzyme levels after vaccination were similar in placeboand vaccine recipients.ConclusionsThe frequency of adverse events post-immunization against YF, accounting for thebackground occurrence of nonspecific signs and symptoms, was shown for the firsttime to be similar for vaccines from 17D and 17DD substrains. The data alsoprovided evidence against viscerotropism of vaccine virus.
其他摘要：ObjectiveTo compare the reactogenicity of three yellow fever (YF) vaccines from WHO-17Dand Brazilian 17DD substrains (different seed-lots) and placebo.MethodsThe study involved 1,087 adults eligible for YF vaccine in Rio de Janeiro, Brazil.Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) wereadministered (“day 0”) following standardized procedures adapted to allow blindingand blocked randomization of participants to coded vaccine types. Adverse eventsafter immunization were ascertained in an interview and in diary forms filled in byeach participant. Liver enzymes were measured on days 0, 4-20 and 30 of the study.Viremia levels were measured on days 4 to 20 of follow-up. The immune responsewas verified through serologic tests.ResultsParticipants were mostly young males. The seroconversion rate was above 98%among those seronegative before immunization. Compared to placebo, the excess riskof any local adverse events ranged from 0.9% to 2.5%, whereas for any systemicadverse events it ranged from 3.5% to 7.4% across vaccine groups. The excess risk ofevents leading to search for medical care or to interruption of work activities rangedfrom 2% to 4.5%. Viremia was detected in 3%-6% of vaccinees up to 10 days aftervaccination. Variations in liver enzyme levels after vaccination were similar in placeboand vaccine recipients.ConclusionsThe frequency of adverse events post-immunization against YF, accounting for thebackground occurrence of nonspecific signs and symptoms, was shown for the firsttime to be similar for vaccines from 17D and 17DD substrains. The data alsoprovided evidence against viscerotropism of vaccine virus.
