Clinical Study of Immunity Duration of Yellow Fever Vaccine in Military

Yellow Fever Vaccine Clinical Trial

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

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03338231
• Other study ID #: ASCLIN 001/2017
• Status: Completed
• Phase: N/A
• First received: November 1, 2017
• Last updated: November 7, 2017
• Start date: March 27, 2017
• Est. completion date: September 4, 2017

Study information

• Verified date: November 2017
• Source: The Immunobiological Technology Institute (Bio-Manguinhos) / Oswaldo Cruz Foundation (Fiocruz)
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

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.

Description:

This is an observational study in young adult males who received the first dose of the yellow fever vaccine in 2009 when they participated in the "Dose-response study of the yellow fever vaccine 17DD produced by Bio-Manguinhos / Fiocruz.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 374
• Est. completion date: September 4, 2017
• Est. primary completion date: September 4, 2017
• Gender: Male
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Participated in the "Dose-response study of the yellow fever vaccine 17DD produced by Bio-Manguinhos / Fiocruz" in 2009.

• Not been revaccinated during the "Dose-response study of the yellow fever vaccine 17DD produced by Bio-Manguinhos / Fiocruz" of 2009.

• Not having received another dose of the 17DD yellow fever vaccine after participating in the 2009 "Bio-Manguinhos / Fiocruz" 17DD yellow fever vaccine dose-response study.

• Provide name, address, telephone and other information so that you can contact if necessary.

• Ability to understand and sign the TCLE.

Exclusion Criteria:

• Impossibility or refusal to collect blood

Related Conditions & MeSH terms

• Fever
• Yellow Fever
• Yellow Fever Vaccine

Locations

Country	Name	City	State
Brazil	Bio-Manguinhos/Fiocruz	Rio de Janeiro

Sponsors (1)

Lead Sponsor	Collaborator
The Immunobiological Technology Institute (Bio-Manguinhos) / Oswaldo Cruz Foundation (Fiocruz)

Country where clinical trial is conducted

Brazil, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of seropositivity participants to YF vaccine as assessed by PRNT.	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	8 years after the 1 st dose of yellow fever vaccine
Secondary	Individual repertoire of immunoglobulins profile as assessed by the PEPperPRINT and phenotypic/functional anti-amaryl memory cell analyse.	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	8 years after the 1 st dose of yellow fever vaccine