Clinical Study of Immunity Duration of Yellow Fever Vaccine in Military
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|ClinicalTrials.gov Identifier: NCT03338231|
Recruitment Status : Completed
First Posted : November 9, 2017
Last Update Posted : November 9, 2017
Yellow fever is an acute viral disease transmitted by mosquitoes in South America, Central America and Africa. It is more prevalente in males gender and the age above 15 years due to the greater exposure in the wild endemic area of yellow fever.
According to the World Health Organization (WHO), a single dose of the yellow fever vaccine is sufficient to maintain protective immunity against yellow fever for a lifetime, therefore a booster dose is not required. This issue is difficult to evaluate because there is no serological correlate of protection against yellow fever and seropositivity is defined with several cut-off points. Although studies indicate that the duration of protection after vaccination is long, many studies have demonstrated a reduction of the antibody titrer over the years. Consequently, there is more concern about people who live in endemic areas. For this reason, Brazil recommends revaccinating once at least until additional studies are performed.
It is important to know the duration of immunity induced by lower doses of YF vaccine. In our knowledge, there is a lack of clinical studies evaluating the immunity duration of the yellow fever vaccine with lower doses. This information is relevant to subsidize the routine recommendation of YF vaccine fractional dose for adults.
|Condition or disease|
|Yellow Fever Vaccine|
|Study Type :||Observational|
|Actual Enrollment :||374 participants|
|Official Title:||Clinical Study of Immunity Duration of Yellow Fever Vaccine in Military, Participants of "Dose-response Study of Yellow Fever Vaccine 17DD Produced by Bio-Manguinhos / Fiocruz" in 2009|
|Actual Study Start Date :||March 27, 2017|
|Actual Primary Completion Date :||September 4, 2017|
|Actual Study Completion Date :||September 4, 2017|
- Number of seropositivity participants to YF vaccine as assessed by PRNT. [ Time Frame: 8 years after the 1 st dose of yellow fever vaccine ]To evaluate the seropositivity by the means of the neutralizing antibody dosage in the participants of the "Dose-response study of the 17DD yellow fever vaccine produced by Bio-Manguinhos/Fiocruz" realized in 2009
- Individual repertoire of immunoglobulins profile as assessed by the PEPperPRINT and phenotypic/functional anti-amaryl memory cell analyse. [ Time Frame: 8 years after the 1 st dose of yellow fever vaccine ]To evaluate individual repertoire of immunoglobulins profile directed to amaryl epitopes by the PEPperPRINT (PEPperCHIP® Yellow Fever Virus Proteome Microarrays) Guidelines and to evaluate the phenotypic and funcional profile of anti-yellow memory cell in the participants of the "Dose-response study of the 17DD yellow fever vaccine produced by Bio-Manguinhos/Fiocruz" realized in 2009
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03338231
|Rio de Janeiro, Brazil, 21040-360|
|Principal Investigator:||Reinaldo M Martins, PhD||Oswaldo Cruz Foundation (Fiocruz)|