Article Text

Effectiveness of case-area targeted interventions including vaccination on the control of epidemic cholera: protocol for a prospective observational study
  1. Ruwan Ratnayake1,2,
  2. Nicolas Peyraud3,
  3. Iza Ciglenecki3,
  4. Etienne Gignoux2,
  5. Maria Lightowler2,
  6. Andrew S Azman3,4,
  7. Primitive Gakima5,
  8. Jean Patrick Ouamba5,
  9. Joseph Amadomon Sagara5,
  10. Rollin Ndombe5,
  11. Nana Mimbu2,
  12. Alexandra Ascorra2,
  13. Epicentre and MSF CATI Working Group,
  14. Placide Okitayemba Welo6,
  15. Elisabeth Mukamba Musenga7,
  16. Berthe Miwanda8,
  17. Yap Boum II9,
  18. Francesco Checchi1,
  19. W John Edmunds1,
  20. Francisco Luquero2,10,
  21. Klaudia Porten2,
  22. Flavio Finger2
    1. 1 Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
    2. 2 Epicentre, Paris, France
    3. 3 Médecins Sans Frontières, Geneva, Switzerland
    4. 4 Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
    5. 5 Medecins Sans Frontieres, Kinshasa and Goma, Congo
    6. 6 Programme National d’Elimination du Choléra et de lutte contre les autres Maladies Diarrhéiques, Kinshasa, Congo (the Democratic Republic of the)
    7. 7 Programme Élargie de Vaccination, Kinshasa, Congo (the Democratic Republic of the)
    8. 8 Institut National de Recherche Biologique, Kinshasa, Congo (the Democratic Republic of the)
    9. 9 Epicentre, Yaoundé, Cameroon
    10. 10 GAVI the Vaccine Alliance, Geneva, Switzerland
    1. Correspondence to Ruwan Ratnayake; ruwan.ratnayake{at}


    Introduction Cholera outbreaks in fragile settings are prone to rapid expansion. Case-area targeted interventions (CATIs) have been proposed as a rapid and efficient response strategy to halt or substantially reduce the size of small outbreaks. CATI aims to deliver synergistic interventions (eg, water, sanitation, and hygiene interventions, vaccination, and antibiotic chemoprophylaxis) to households in a 100—250 m ‘ring’ around primary outbreak cases.

    Methods and analysis We report on a protocol for a prospective observational study of the effectiveness of CATI. Médecins Sans Frontières (MSF) plans to implement CATI in the Democratic Republic of the Congo (DRC), Cameroon, Niger and Zimbabwe. This study will run in parallel to each implementation. The primary outcome is the cumulative incidence of cholera in each CATI ring. CATI will be triggered immediately on notification of a case in a new area. As with most real-world interventions, there will be delays to response as the strategy is rolled out. We will compare the cumulative incidence among rings as a function of response delay, as a proxy for performance. Cross-sectional household surveys will measure population-based coverage. Cohort studies will measure effects on reducing incidence among household contacts and changes in antimicrobial resistance.

    Ethics and dissemination The ethics review boards of MSF and the London School of Hygiene and Tropical Medicine have approved a generic protocol. The DRC and Niger-specific versions have been approved by the respective national ethics review boards. Approvals are in process for Cameroon and Zimbabwe. The study findings will be disseminated to the networks of national cholera control actors and the Global Task Force for Cholera Control using meetings and policy briefs, to the scientific community using journal articles, and to communities via community meetings.

    • epidemiology
    • public health
    • infection control
    • geographical mapping

    This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

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    • Collaborators Epicentre and MSF CATI Working Group : Médecins Sans Frontières (MSF), Spain: Miriam Alia. Epicentre, Niger: Bachir Assao, Abdoul-Moumouni Issa-Soumana, Oumar Touré. Médecins Sans Frontières (MSF), Belgium: Catherine Bachy, Rob D'hondt, Isabella Panunzi. London School of Hygiene & Tropical Medicine (LSHTM): Lauren D'Mello-Guyett. Epicentre, Cameroon: Karl Njuwa Fai, Rodrigue Ntone. Médecins Sans Frontières (MSF), Switzerland: Caroline Henry-Ostian. Médecins Sans Frontières (MSF), Zimbabwe: Danish Malik, Herbert Mutubuki. Epicentre, France: Issaka Soumana, Mamady Traore.

    • Contributors RR, FF, FL, FC, JE, NP, IC, EG, ML, ASA, PG, PO, JAS, RN, NM, AA and KP conceived of and led the design of the study. RR and FF led the writing of the protocol and the article. RN and AA provided specific advice on laboratory methods. The CATI and MSF Working Group contributed to the design of the study. All other authors (including PO, EMM, BM, YBII) and all working group members (MA, BA, CB, RdH, LDG, KNF, CH, AI, DM, HB, RN, IP, IS, OT, MT) contributed to the design of the study. All authors and working group members revised the draft and approved the final manuscript. RR and FF are the guarantors of the overall content of the protocol and the article. RR, FF, EG, ML, NM,and YBII will lead the planning of the study and will oversee study implementation and data acquisition. RR and FF will lead the statistical analysis and interpretation, and the reporting of the results.

    • Funding This research is internally funded by Médecins Sans Frontières and therefore received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. RR is funded by a Doctoral Foreign Study Award from the Canadian Institutes of Health Research (award number DFS-164266). FC and WJE are funded by UK Research and Innovation as part of the Global Challenges Research Fund (grant number ES/P010873/1).

    • Competing interests None declared.

    • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.