A mass vaccination campaign targeting adults and children to prevent typhoid fever in Hechi; expanding the use of Vi polysaccharide vaccine in southeast China: a cluster-randomized trial.
BACKGROUND
One of the goals of this study was to learn the coverage, safety and logistics of a mass vaccination campaign against typhoid fever in children and adults using locally produced typhoid Vi polysaccharide (PS) and group A meningococcal PS vaccines in southern China.


METHODS
The vaccination campaign targeted 118,588 persons in Hechi, Guangxi Province, aged between 5 to 60 years, in 2003. The study area was divided into 107 geographic clusters, which were randomly allocated to receive one of the single-dose parenteral vaccines. All aspects regarding vaccination logistics, feasibility and safety were documented and systematically recorded. Results of the logistics, feasibility and safety are reported.


RESULTS
The campaign lasted 5 weeks and the overall vaccination coverage was 78%. On average, the 30 vaccine teams gave immunizations on 23 days. Vaccine rates were higher in those aged < or = 15 years (90%) than in adolescents and young adults (70%). Planned mop-up activities increased the coverage by 17%. The overall vaccine wastage was 11%. The cold chain was maintained and documented. 66 individuals reported of adverse events out of all vaccinees, where fever (21%), malaise (19%) and local redness (19%) were the major symptoms; no life-threatening event occurred. Three needle-sharp events were reported.


CONCLUSIONS
The mass immunization proved feasible and safe, and vaccine coverage was high. Emphasis should be placed on: injection safety measures, community involvement and incorporation of mop-up strategies into any vaccination campaign. School-based and all-age Vi mass immunizations programs are potentially important public health strategies for prevention of typhoid fever in high-risk populations in southern China.
Yang
Jin
J
Division of Bacterial Diseases, Guangxi Center for Disease Control, 80 Taoyuan Road, Nanning 530021, Guangxi, China. yyyjin@hotmail.com
Acosta
Camilo J
CJ
Si
Guo-ai
GA
Zeng
Jun
J
Li
Cui-yun
CY
Liang
Da-bin
DB
Ochiai
R Leon
RL
Page
Anne-Laure
AL
Danovaro-Holliday
M Carolina
MC
Zhang
Jie
J
Zhou
Bao-de
BD
Liao
He-zhuang
HZ
Wang
Ming-liu
ML
Tan
Dong-mei
DM
Tang
Zhen-zhu
ZZ
Gong
Jian
J
Park
Jin-kyung
JK
Ali
Mohammad
M
Ivanoff
Bernard
B
Liang
Gui-chen
GC
Yang
Hong-hui
HH
Pang
Tikki
T
Xu
Zhi-yi
ZY
Donner
Allan
A
Galindo
Claudia M
CM
Dong
Bai-qing
BQ
Clemens
John D
JD
D000293:Adolescent; D000328:Adult; D000942:Antigens, Bacterial / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D005240:Feasibility Studies; D005843:Geography; D006801:Humans; D007273:Injections, Intramuscular; D007279:Injections, Subcutaneous; D032541:Mass Vaccination / Q000458:organization & administration*; D008585:Meningitis, Meningococcal / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000008:administration & dosage / Q000009:adverse effects; D008875:Middle Aged; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage* / Q000009:adverse effects; D011635:Public Health Administration; D012449:Safety; D040241:Social Marketing; D014435:Typhoid Fever / Q000453:epidemiology / Q000517:prevention & control*; D014436:Typhoid-Paratyphoid Vaccines / Q000008:administration & dosage* / Q000009:adverse effects
D000942:Antigens, Bacterial; D022401:Meningococcal Vaccines; D011135:Polysaccharides, Bacterial; D014436:Typhoid-Paratyphoid Vaccines