TY - JOUR
T1 - Effectiveness of oral cholera vaccine in preventing cholera among fishermen in Lake Chilwa, Malawi
T2 - A case-control study
AU - Grandesso, Francesco
AU - Kasambara, Watipaso
AU - Page, Anne Laure
AU - Debes, Amanda K.
AU - M'bang'ombe, Maurice
AU - Palomares, Adriana
AU - Lechevalier, Pauline
AU - Pezzoli, Lorenzo
AU - Alley, Ian
AU - Salumu, Leon
AU - Msyamboza, Kelias
AU - Sack, David
AU - Cohuet, Sandra
AU - Luquero, Francisco Javier
N1 - Funding Information:
This work was funded by Médecins Sans Frontières (MSF), Operational Centre Paris. MSF national and international personnel collaborated and supported the implementation of the study.
Publisher Copyright:
© 2019
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019/6/19
Y1 - 2019/6/19
N2 - Background: In response to a cholera outbreak among mobile, difficult-to-reach fishermen on Lake Chilwa, Malawi in 2016, a novel vaccine distribution strategy exploited the proven vaccine thermostability. Fishermen, while taking the first vaccine dose under supervision, received the second dose in a sealed bag, and were told to drink it two weeks later. This study assessed short-term vaccine protection of this strategy. Methods: Patients with diarrhoea admitted to health facilities around lake were interviewed and a stool sample collected for PCR testing. Vaccine effectiveness was assessed in a case-control test-negative design by comparing cases (PCR-positive for V. cholerae O1) and controls (patients with diarrhoea but PCR-negative) and with the screening method that compared the proportions of vaccinated among cholera cases versus the general fishermen population. Results: Of 145 study participants, 120 were fishermen living on the lake. Vaccine effectiveness at three-months was 90.0% [95% CI: 38.8; 98.4] among fishermen and 83.3% [95% CI: 20.8; 96.5] among all participants in the case-control test-negative design, and 97.5% [95% CI: 90.9; 99.3] with the screening method. Conclusion: This strategy was effective in providing short-term protection in fishermen against cholera. Further research is needed to determine the adding value of the second dose and to identify the optimal vaccination strategies for different contexts.
AB - Background: In response to a cholera outbreak among mobile, difficult-to-reach fishermen on Lake Chilwa, Malawi in 2016, a novel vaccine distribution strategy exploited the proven vaccine thermostability. Fishermen, while taking the first vaccine dose under supervision, received the second dose in a sealed bag, and were told to drink it two weeks later. This study assessed short-term vaccine protection of this strategy. Methods: Patients with diarrhoea admitted to health facilities around lake were interviewed and a stool sample collected for PCR testing. Vaccine effectiveness was assessed in a case-control test-negative design by comparing cases (PCR-positive for V. cholerae O1) and controls (patients with diarrhoea but PCR-negative) and with the screening method that compared the proportions of vaccinated among cholera cases versus the general fishermen population. Results: Of 145 study participants, 120 were fishermen living on the lake. Vaccine effectiveness at three-months was 90.0% [95% CI: 38.8; 98.4] among fishermen and 83.3% [95% CI: 20.8; 96.5] among all participants in the case-control test-negative design, and 97.5% [95% CI: 90.9; 99.3] with the screening method. Conclusion: This strategy was effective in providing short-term protection in fishermen against cholera. Further research is needed to determine the adding value of the second dose and to identify the optimal vaccination strategies for different contexts.
KW - Cholera
KW - Effectiveness
KW - Hard-to-reach populations
KW - Malawi
KW - Thermostability
KW - Vaccine
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U2 - 10.1016/j.vaccine.2019.05.044
DO - 10.1016/j.vaccine.2019.05.044
M3 - Article
C2 - 31133470
AN - SCOPUS:85066089271
SN - 0264-410X
VL - 37
SP - 3668
EP - 3676
JO - Vaccine
JF - Vaccine
IS - 28
ER -