A multi-country cluster randomized controlled effectiveness evaluation to accelerate the introduction of Vi polysaccharide typhoid vaccine in developing countries in Asia: rationale and design.
Phase-III vaccine efficacy trials typically employ individually randomized designs intended to ensure that measurements of vaccine protective efficacy reflect only direct vaccine effects. As a result, decisions about introducing newly licensed vaccines into public health programmes often fail to consider the substantially greater protection that may occur when a vaccine is deployed in public health programmes, due to the combination of direct plus indirect vaccine protective effects. Vaccine total protection can be better evaluated with cluster randomized trials. Such a design was considered to generate policy relevant data to accelerate the rationale introduction of the licensed typhoid fever Vi polysaccharide (PS) vaccine in Asia by the Diseases of the Most Impoverished (DOMI) typhoid fever programme. The DOMI's programme multi-country study is one of the largest cluster randomized vaccine trials ever mounted in Asia, which includes approximately 200,000 individuals. Its main objective is to determine the effectiveness of a licensed Vi PS vaccine. The rationale and design of this study are discussed. Preliminary results are presented that determined the final planning of the trial before immunization. Important methodological and practical issues regarding vaccine cluster randomized designs are illustrated.
Acosta
Camilo J
CJ
International Vaccine Institute, Seoul, South Korea. camilo_acosta2003@yahoo.com
Galindo
Claudia M
CM
Ali
Mohammad
M
Elyazeed
Remon Abu
RA
Ochiai
R Leon
RL
Danovaro-Holliday
M Carolina
MC
Page
Anne-Laure
AL
Thiem
Vu Dinh
VD
Jin
Yang
Y
Park
Jin Kyung
JK
Lee
Hyejon
H
Puri
Mahesh K
MK
Ivanoff
Bernard
B
Agtini
Magdarina D
MD
Soeharno
Rooswanti
R
Simanjuntak
Cyrus H
CH
Punjabi
Narain H
NH
Canh
Do Gia
DG
Sur
Dipika
D
Nizami
Qamaruddin
Q
Manna
Byomkesh
B
Bai-qing
Dong
D
Anh
Dang Duc
DD
Honghui
Yang
Y
Bhattacharya
Sujit Kumar
SK
Bhutta
Zulfikar
Z
Trach
Dang Duc
DD
Xu
Zhi-Yi
ZY
Pang
Tikki
T
Donner
Allan
A
Clemens
John D
JD
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D003906:Developing Countries; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D007223:Infant; D008875:Middle Aged; D010154:Pakistan / Q000453:epidemiology; D010342:Patient Acceptance of Health Care; D011135:Polysaccharides, Bacterial / Q000009:adverse effects / Q000627:therapeutic use*; D011159:Population Surveillance / Q000379:methods; D015995:Prevalence; D012485:Salmonella typhi / Q000302:isolation & purification; D014435:Typhoid Fever / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D014436:Typhoid-Paratyphoid Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D014744:Vietnam / Q000453:epidemiology
D011135:Polysaccharides, Bacterial; D014436:Typhoid-Paratyphoid Vaccines; C057664:Vi polysaccharide vaccine, typhoid