Scientific Publications by FDA Staff

Hum Vaccin Immunother 2016 Feb;12(2):491-502

Booster dose after 10 years is recommended following 17DD-YF primary vaccination.

Campi-Azevedo AC, Costa-Pereira C, Antonelli LR, Fonseca CT, Teixeira-Carvalho A, Villela-Rezende G, Santos RA, Batista MA, Campos FM, Pacheco-Porto L, Junior OA, Hossell DM, Coelho-Dos-Reis JG, Peruhype-Magalhaes V, Costa-Silva MF, de Oliveira JG, Farias RH, Noronha TN, Lemos JA, von Doellinger VD, Simoes M, de Souza MM, Malaquias LC, Persi HR, Pereira JM, Martins JA, Dornelas-Ribeiro M, Vinhas AA, Alves TR, Maia ML, Freire MD, Martins RM, Homma A, Romano AP, Domingues CM, Tauil PL, Vasconcelos PF, Rios M, Caldas IR, Camacho LA, Martins-Filho OA

A single vaccination of Yellow Fever vaccines is believed to confer life-long protection. In this study, results of vaccinees who received a single dose of 17DD-YF immunization followed over 10 years challenge this premise. YF-neutralizing antibodies, subsets of memory T and B cells as well as cytokine-producing lymphocytes were evaluated in groups of adults before (NVday0) and after (PVday30-45, PVyear1-4, PVyear5-9, PVyear10-11, PVyear12-13) 17DD-YF primary vaccination. YF-neutralizing antibodies decrease significantly from PVyear1-4 to PVyear12-13 as compared to PVday30-45, and the seropositivity rates (PRNT>/=2.9Log10mIU/mL) become critical (lower than 90%) beyond PVyear5-9. YF-specific memory phenotypes (effector T-cells and classical B-cells) significantly increase at PVday30-45 as compared to naive baseline. Moreover, these phenotypes tend to decrease at PVyear10-11 as compared to PVday30-45. Decreasing levels of TNF-alpha+ and IFN-gamma+ produced by CD4+ and CD8+ T-cells along with increasing levels of IL-10+CD4+T-cells were characteristic of anti-YF response over time. Systems biology profiling represented by hierarchic networks revealed that while the naive baseline is characterized by independent micro-nets, primary vaccinees displayed an imbricate network with essential role of central and effector CD8+ memory T-cell responses. Any putative limitations of this cross-sectional study will certainly be answered by the ongoing longitudinal population-based investigation. Overall, our data support the current Brazilian national immunization policy guidelines that recommend one booster dose 10 years after primary 17DD-YF vaccination.