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Lemaitre J, Pasetto D, Perez-Saez J, Sciarra C, Wamala JF, Rinaldo A. Rainfall as a driver of epidemic cholera: Comparative model assessments of the effect of intra-seasonal precipitation events. Acta Trop 2019; 190:235-243. [PMID: 30465744 DOI: 10.1016/j.actatropica.2018.11.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 11/04/2018] [Accepted: 11/14/2018] [Indexed: 01/18/2023]
Abstract
The correlation between cholera epidemics and climatic drivers, in particular seasonal tropical rainfall, has been studied in a variety of contexts owing to its documented relevance. Several mechanistic models of cholera transmission have included rainfall as a driver by focusing on two possible transmission pathways: either by increasing exposure to contaminated water (e.g. due to worsening sanitary conditions during water excess), or water contamination by freshly excreted bacteria (e.g. due to washout of open-air defecation sites or overflows). Our study assesses the explanatory power of these different modeling structures by formal model comparison using deterministic and stochastic models of the type susceptible-infected-recovered-bacteria (SIRB). The incorporation of rainfall effects is generalized using a nonlinear function that can increase or decrease the relative importance of the large precipitation events. Our modelling framework is tested against the daily epidemiological data collected during the 2015 cholera outbreak within the urban context of Juba, South Sudan. This epidemic is characterized by a particular intra-seasonal double peak on the incidence in apparent relation with particularly strong rainfall events. Our results show that rainfall-based models in both their deterministic and stochastic formulations outperform models that do not account for rainfall. In fact, classical SIRB models are not able to reproduce the second epidemiological peak, thus suggesting that it was rainfall-driven. Moreover we found stronger support across model types for rainfall acting on increased exposure rather than on exacerbated water contamination. Although these results are context-specific, they stress the importance of a systematic and comprehensive appraisal of transmission pathways and their environmental forcings when embarking in the modelling of epidemic cholera.
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Affiliation(s)
- Joseph Lemaitre
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
| | - Damiano Pasetto
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
| | - Javier Perez-Saez
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
| | - Carla Sciarra
- Dipartimento di Ingegneria dell'Ambiente, del Territorio e delle Infrastrutture, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy.
| | | | - Andrea Rinaldo
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Dipartimento ICEA, Università di Padova, 35100 Padova, Italy.
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The cholera outbreak in Yemen: lessons learned and way forward. BMC Public Health 2018; 18:1338. [PMID: 30514336 PMCID: PMC6278080 DOI: 10.1186/s12889-018-6227-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 11/19/2018] [Indexed: 01/05/2023] Open
Abstract
The Yemen cholera outbreak has been driven by years of conflict and has now become the largest in epidemiologically recorded history with more than 1.2 million cases since the beginning of the outbreak in April, 2017. In this report we review and discuss the cholera management strategies applied by the major international humanitarian health organizations present in Yemen. We find the response by the organizations examined to have been more focused on case management than on outbreak prevention. Oral Cholera Vaccines (OCVs) were not delivered until nearly 16 months into the outbreak. A recent scale-up of the global OCV stockpile will hopefully allow for rapid mass deployment of the OCV in future humanitarian emergencies. Continuous funding to this stockpile will be crucial to maintain this option for prevention and control of cholera outbreaks. Of equal importance will be the timely recognition of the need for mass OCV deployment and development of more specific, comprehensive and actionable evidence-based frameworks to help guide this decision, however difficult this may be. The outbreak highlights the importance for international humanitarian health organizations to have a continuous discussion about whether and to what extent they should increase their focus on pre-emptively addressing the environmental determinants of communicable diseases in humanitarian emergencies. Strong advocacy from the public health community for peace and the protection of human health, by bringing to attention the public health impacts of armed conflict and keeping the world’s political leaders accountable to their actions, will remain crucial.
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Lewnard JA, Tedijanto C, Cowling BJ, Lipsitch M. Measurement of Vaccine Direct Effects Under the Test-Negative Design. Am J Epidemiol 2018; 187:2686-2697. [PMID: 30099505 PMCID: PMC6269249 DOI: 10.1093/aje/kwy163] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/30/2018] [Accepted: 07/30/2018] [Indexed: 01/17/2023] Open
Abstract
Test-negative designs are commonplace in assessments of influenza vaccination effectiveness, estimating this value from the exposure odds ratio of vaccination among individuals treated for acute respiratory illness who test positive for influenza virus infection. This approach is widely believed to recover the vaccine direct effect by correcting for differential health-care-seeking behavior among vaccinated and unvaccinated persons. However, the relationship of the measured odds ratio to true vaccine effectiveness is poorly understood. We derived the odds ratio under circumstances of real-world test-negative studies. The odds ratio recovers the vaccine direct effect when 2 conditions are met: 1) Individuals' vaccination decisions are uncorrelated with exposure or susceptibility to the test-positive or test-negative conditions, and 2) vaccination confers "all-or-nothing" protection (whereby certain individuals have no protection while others are perfectly protected). Biased effect-size estimates arise if either condition is unmet. Such bias might suggest misleading associations of vaccine effectiveness with time since vaccination or the force of infection of influenza. The test-negative design could also fail to correct for differential health-care-seeking behavior among vaccinated and unvaccinated persons without stringent criteria for enrollment and testing. Our findings demonstrate a need to reassess how data from test-negative studies can inform policy decisions.
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Affiliation(s)
- Joseph A Lewnard
- Division of Epidemiology, School of Public Health, University of California, Berkeley, California
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Christine Tedijanto
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Benjamin J Cowling
- World Health Organization Collaborating Center for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Marc Lipsitch
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
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Abstract
With one-third of nations at risk of cholera, we can expect to experience massive, rapidly disseminated, and prolonged cholera outbreaks such as those recently experienced in Yemen and Haiti. The prevention of cholera outbreaks like these includes the provision of potable water, sanitation, and hygiene (WASH). This approach has been known for generations. However, it will be many years before universal global access to WASH is achieved. While working toward universal WASH, study data has shown that licensed and WHO prequalified cholera vaccines are important tools for cholera prevention. Oral inactivated whole-cell vaccines such as Shanchol and Euvichol-plus provide well-documented direct benefits to vaccine recipients and to the unimmunized through herd protection. Manufacturers have now increased the cholera vaccine supply, and since 2013 vaccine doses have been available for emergency and endemic control through a global stockpile. Advances in packaging and vaccine temperature control, reduced vaccine costs, the inclusion of pregnant women in vaccine campaigns, and a targeted approach to high incidence endemic areas are further increasing the usefulness of these vaccines for reducing the global cholera burden.
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Odevall L, Hong D, Digilio L, Sahastrabuddhe S, Mogasale V, Baik Y, Choi S, Kim JH, Lynch J. The Euvichol story - Development and licensure of a safe, effective and affordable oral cholera vaccine through global public private partnerships. Vaccine 2018; 36:6606-6614. [PMID: 30314912 PMCID: PMC6203809 DOI: 10.1016/j.vaccine.2018.09.026] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 09/11/2018] [Accepted: 09/12/2018] [Indexed: 01/04/2023]
Abstract
Cholera, a diarrheal disease primarily affecting vulnerable populations in developing countries, is estimated to cause disease in more than 2.5 million people and kill almost 100,000 annually. An oral cholera vaccine (OCV) has been available globally since 2001; the demand for this vaccine from affected countries has however been very low, due to various factors including vaccine price and mode of administration. The low demand for the vaccine and limited commercial incentives to invest in research and development of vaccines for developing country markets has kept the global supply of OCVs down. Since 1999, the International Vaccine Institute has been committed to make safe, effective and affordable OCVs accessible. Through a variety of partnerships with collaborators in Sweden, Vietnam, India and South Korea, and with public and private funding, IVI facilitated development and production of two affordable and WHO-prequalified OCVs and together with other stakeholders accelerated the introduction of these vaccines for the global public-sector market.
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Affiliation(s)
- Lina Odevall
- Life Science Consultant, Gothenburg, Sweden; International Vaccine Institute, Seoul, Republic of Korea.
| | - Deborah Hong
- International Vaccine Institute, Seoul, Republic of Korea; Médecins Sans Frontières, Seoul, Republic of Korea
| | - Laura Digilio
- International Vaccine Institute, Seoul, Republic of Korea
| | | | | | | | | | - Jerome H Kim
- International Vaccine Institute, Seoul, Republic of Korea
| | - Julia Lynch
- International Vaccine Institute, Seoul, Republic of Korea
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Grandesso F, Rafael F, Chipeta S, Alley I, Saussier C, Nogareda F, Burns M, Lechevalier P, Page AL, Salumu L, Pezzoli L, Mwesawina M, Cavailler P, Mengel M, Luquero FJ, Cohuet S. Oral cholera vaccination in hard-to-reach communities, Lake Chilwa, Malawi. Bull World Health Organ 2018; 96:817-825. [PMID: 30505029 PMCID: PMC6249704 DOI: 10.2471/blt.17.206417] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 08/24/2018] [Accepted: 08/27/2018] [Indexed: 01/14/2023] Open
Abstract
Objective To evaluate vaccination coverage, identify reasons for non-vaccination and assess satisfaction with two innovative strategies for distributing second doses in an oral cholera vaccine campaign in 2016 in Lake Chilwa, Malawi, in response to a cholera outbreak. Methods We performed a two-stage cluster survey. The population interviewed was divided in three strata according to the second-dose vaccine distribution strategy: (i) a standard strategy in 1477 individuals (68 clusters of 5 households) on the lake shores; (ii) a simplified cold-chain strategy in 1153 individuals (59 clusters of 5 households) on islands in the lake; and (iii) an out-of-cold-chain strategy in 295 fishermen (46 clusters of 5 to 15 fishermen) in floating homes, called zimboweras. Finding Vaccination coverage with at least one dose was 79.5% (1153/1451) on the lake shores, 99.3% (1098/1106) on the islands and 84.7% (200/236) on zimboweras. Coverage with two doses was 53.0% (769/1451), 91.1% (1010/1106) and 78.8% (186/236), in the three strata, respectively. The most common reason for non-vaccination was absence from home during the campaign. Most interviewees liked the novel distribution strategies. Conclusion Vaccination coverage on the shores of Lake Chilwa was moderately high and the innovative distribution strategies tailored to people living on the lake provided adequate coverage, even among hard-to-reach communities. Community engagement and simplified delivery procedures were critical for success. Off-label, out-of-cold-chain administration of oral cholera vaccine should be considered as an effective strategy for achieving high coverage in hard-to-reach communities. Nevertheless, coverage and effectiveness must be monitored over the short and long term.
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Affiliation(s)
| | | | - Sikhona Chipeta
- Directorate of Preventive Health Services, Ministry of Health, Lilongwe, Malawi
| | - Ian Alley
- Epicentre, 8 rue Saint-Sabin, 75011 Paris, France
| | | | - Francisco Nogareda
- Department of Infectious Hazard Management, World Health Organization, Geneva, Switzerland
| | | | | | | | | | - Lorenzo Pezzoli
- Department of Infectious Hazard Management, World Health Organization, Geneva, Switzerland
| | - Maurice Mwesawina
- Directorate of Preventive Health Services, Ministry of Health, Lilongwe, Malawi
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Hunter-Adams J, Battersby J, Oni T. Fault lines in food system governance exposed: reflections from the listeria outbreak in South Africa. ACTA ACUST UNITED AC 2018. [DOI: 10.1080/23748834.2018.1508326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Jo Hunter-Adams
- Health Economics Unit, School of Public Health and Family Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Jane Battersby
- African Centre for Cities, University of Cape Town, Cape Town, South Africa
| | - Tolu Oni
- Division of Public Health Medicine, School of Public Health and Family Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- MRC Epidemiology Unit, Institute of Metabolic Science Building, University of Cambridge, Cambridge, UK
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58
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Rebaudet S, Gaudart J, Piarroux R. Vaccination against cholera in Juba. THE LANCET. INFECTIOUS DISEASES 2018; 17:479-480. [PMID: 28447951 DOI: 10.1016/s1473-3099(17)30189-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 03/10/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Stanislas Rebaudet
- Assistance Publique-Hôpitaux de Marseille, Hôpital de la Timone, 13385 Marseille cedex 05, France.
| | - Jean Gaudart
- Assistance Publique-Hôpitaux de Marseille, Hôpital de la Timone, 13385 Marseille cedex 05, France; Aix-Marseille University, IRD, INSERM, SESSTIM, Marseille, France; Aix-Marseille University, UMR MD3, Marseille, France
| | - Renaud Piarroux
- Assistance Publique-Hôpitaux de Marseille, Hôpital de la Timone, 13385 Marseille cedex 05, France
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Ciglenecki I, Azman AS, Rumunu J, Cabrol JC, Luquero FJ. Vaccination against cholera in Juba - Authors' reply. THE LANCET. INFECTIOUS DISEASES 2018; 17:480-481. [PMID: 28447952 DOI: 10.1016/s1473-3099(17)30184-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 03/24/2017] [Indexed: 11/30/2022]
Affiliation(s)
| | - Andrew S Azman
- Médecins Sans Frontières, Geneva 1202, Switzerland; Department of Epidemiology, Johns Hopkins University, Baltimore, MD, USA
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60
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Abstract
PURPOSE OF REVIEW This review describes the basic epidemiologic, clinical, and microbiologic aspects of cholera, highlights new developments within these areas, and presents strategies for applying currently available tools and knowledge more effectively. RECENT FINDINGS From 1990 to 2016, the reported global burden of cholera fluctuated between 74,000 and 595,000 cases per year; however, modeling estimates suggest the real burden is between 1.3 and 4.0 million cases and 95,000 deaths yearly. In 2018, the World Health Assembly endorsed a new initiative to reduce cholera deaths by 90% and eliminate local cholera transmission in 20 countries by 2030. New tools, including localized GIS mapping, climate modeling, whole genome sequencing, oral vaccines, rapid diagnostic tests, and new applications of water, sanitation, and hygiene interventions, could support this goal. Challenges include a high proportion of fragile states among cholera-endemic countries, urbanization, climate change, and the need for cholera treatment guidelines for pregnant women and malnourished children. SUMMARY Reducing cholera morbidity and mortality depends on real-time surveillance, outbreak detection and response; timely access to appropriate case management and cholera vaccines; and provision of safe water, sanitation, and hygiene.
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Affiliation(s)
- William Davis
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Mailstop H24-9, Atlanta, GA 30329, USA
| | - Rupa Narra
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Mailstop H24-9, Atlanta, GA 30329, USA
| | - Eric D. Mintz
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, Mailstop H24-9, Atlanta, GA 30329, USA
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61
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Protection from killed oral cholera vaccine continues for 4 years. THE LANCET GLOBAL HEALTH 2018; 6:e946-e947. [DOI: 10.1016/s2214-109x(18)30311-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 06/19/2018] [Indexed: 11/23/2022] Open
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Chatterjee P, Kanungo S, Dutta S. Challenges for programmatic implementation of killed whole cell oral cholera vaccines for prevention and control of cholera: a meta-opinion. Expert Opin Biol Ther 2018; 18:983-988. [PMID: 30107757 DOI: 10.1080/14712598.2018.1512578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Cholera remains a public health threat. The development of safe, effective, easy-to-administer, heat-stable, and cheap killed whole cell oral cholera vaccines (OCVs) has provided an additional tool to counter cholera. In this meta-opinion, we review the challenges of delivering OCVs through the existing public health infrastructure in vulnerable areas. AREAS COVERED We provide an overview of the available vaccines against cholera, the existing evidence about the effectiveness of a two-dose as well as a single-dose OCV strategy. We also highlight the experience from the public health campaigns for OCV deployment. EXPERT OPINION Several public health experiences have shown the feasibility of incorporating OCVs into the public health response against cholera. Combined with a comprehensive water, sanitation, and hygiene (WaSH) improvement plan, OCVs need to be deployed in identified vulnerable areas, targeting the highest risk groups first. Vaccination programs should not be deployed in lieu of investments in WaSH services, but as a complimentary service in a comprehensive, cholera control intervention package. It has been a challenge to have high two-dose coverage across all eligible recipients, necessitating the adoption of innovative strategies to boost coverage. Longer intervals between doses may help to overcome resource and logistical limitations enabling higher coverage.
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Affiliation(s)
- Pranab Chatterjee
- a National Institute of Cholera and Enteric Disease - Division of Epidemiology , Indian Council of Medical Research , Kolkata , India
| | - Suman Kanungo
- a National Institute of Cholera and Enteric Disease - Division of Epidemiology , Indian Council of Medical Research , Kolkata , India
| | - Shanta Dutta
- b National Institute of Cholera and Enteric Diseases , Indian Council of Medical Research , Kolkata , India
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Sublingual Adjuvant Delivery by a Live Attenuated Vibrio cholerae-Based Antigen Presentation Platform. mSphere 2018; 3:3/3/e00245-18. [PMID: 29875145 PMCID: PMC5990885 DOI: 10.1128/msphere.00245-18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 05/16/2018] [Indexed: 01/06/2023] Open
Abstract
Diarrheal disease is the most common infectious disease of children in the developing world. Our goal is to develop a diarrheal antigen presentation platform based on whole Vibrio cholerae cells that does not depend on protein purification. We have previously shown the feasibility of genetically fusing antigens to the V. cholerae biofilm matrix protein RbmA for presentation on the cell surface. A mucosal adjuvant could improve immunogenicity of such a vaccine at the mucosal surface. Here we engineer a live attenuated V. cholerae vaccine to constitutively synthesize mmCT, a nontoxic form of cholera toxin. When this vaccine is delivered sublingually, in vivo-synthesized mmCT acts as both an adjuvant and antigen. This could greatly increase the magnitude and duration of the immune response elicited by codelivered heterologous antigens. A sublingually delivered heterologous antigen presentation platform that does not depend on antigen or adjuvant purification would be of great benefit in protection against diarrheal disease. In proof-of-concept studies, we previously showed that when a fusion protein comprised of the Vibrio cholerae biofilm matrix protein RbmA and the B subunit of cholera toxin (R-CTB) is expressed from a plasmid within V. cholerae, R-CTB is sequestered in the biofilm matrix, leading to decoration of the cell surface. Sublingual delivery of live attenuated R-CTB-decorated cells results in a mucosal immune response to CTB. To improve the immune response to diarrheal antigens presented by this platform, we have engineered our live attenuated vaccine to express the mucosal adjuvant mmCT (i.e., multiply mutated CT). Here we report that delivery of this adjuvant via sublingual administration of our vaccine enhances the mucosal immune response to V. cholerae LPS and elicits a systemic and mucosal immune response to CTB. However, provision of R-CTB with mmCT selectively blunts the mucosal immune response to CTB. We propose that mmCT delivered by this live attenuated Vibrio cholerae vaccine platform may serve as a mucosal adjuvant for heterologous antigens, provided they are not too similar to mmCT. IMPORTANCE Diarrheal disease is the most common infectious disease of children in the developing world. Our goal is to develop a diarrheal antigen presentation platform based on whole Vibrio cholerae cells that does not depend on protein purification. We have previously shown the feasibility of genetically fusing antigens to the V. cholerae biofilm matrix protein RbmA for presentation on the cell surface. A mucosal adjuvant could improve immunogenicity of such a vaccine at the mucosal surface. Here we engineer a live attenuated V. cholerae vaccine to constitutively synthesize mmCT, a nontoxic form of cholera toxin. When this vaccine is delivered sublingually, in vivo-synthesized mmCT acts as both an adjuvant and antigen. This could greatly increase the magnitude and duration of the immune response elicited by codelivered heterologous antigens.
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Lopez AL, Deen J, Azman AS, Luquero FJ, Kanungo S, Dutta S, von Seidlein L, Sack DA. Immunogenicity and Protection From a Single Dose of Internationally Available Killed Oral Cholera Vaccine: A Systematic Review and Metaanalysis. Clin Infect Dis 2018; 66:1960-1971. [PMID: 29177437 PMCID: PMC5982790 DOI: 10.1093/cid/cix1039] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/19/2017] [Indexed: 12/16/2022] Open
Abstract
In addition to improved water supply and sanitation, the 2-dose killed oral cholera vaccine (OCV) is an important tool for the prevention and control of cholera. We aimed to document the immunogenicity and protection (efficacy and effectiveness) conferred by a single OCV dose against cholera. The metaanalysis showed that an estimated 73% and 77% of individuals seroconverted to the Ogawa and Inaba serotypes, respectively, after an OCV first dose. The estimates of single-dose vaccine protection from available studies are 87% at 2 months decreasing to 33% at 2 years. Current immunologic and clinical data suggest that protection conferred by a single dose of killed OCV may be sufficient to reduce short-term risk in outbreaks or other high-risk settings, which may be especially useful when vaccine supply is limited. However, until more data suggest otherwise, a second dose should be given as soon as circumstances allow to ensure robust protection.
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Affiliation(s)
- Anna Lena Lopez
- Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines, Manila
- Delivering Oral Vaccine Effectively, Department of International Health, Johns Hopkins University, Baltimore, Maryland
| | - Jacqueline Deen
- Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines, Manila
- Delivering Oral Vaccine Effectively, Department of International Health, Johns Hopkins University, Baltimore, Maryland
| | - Andrew S Azman
- Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland
| | | | - Suman Kanungo
- National Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata, West Bengal, India
| | - Shanta Dutta
- National Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata, West Bengal, India
| | - Lorenz von Seidlein
- Delivering Oral Vaccine Effectively, Department of International Health, Johns Hopkins University, Baltimore, Maryland
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - David A Sack
- Delivering Oral Vaccine Effectively, Department of International Health, Johns Hopkins University, Baltimore, Maryland
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Deen J, von Seidlein L. The case for ring vaccinations with special consideration of oral cholera vaccines. Hum Vaccin Immunother 2018; 14:2069-2074. [PMID: 29630444 PMCID: PMC6149944 DOI: 10.1080/21645515.2018.1462068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 03/21/2018] [Indexed: 01/09/2023] Open
Abstract
Ring vaccinations create a zone of immune contacts around a case to prevent further disease transmission and have been successfully employed in the eradication of smallpox and the control of other infections. Millions of oral cholera vaccine (OCV) doses have been effectively deployed through mass vaccination campaigns. But there are situations when the OCV supply, resources, and time are limited and alternative strategies need to be considered. People living in close proximity of cholera cases often share risk factors such as contaminated water supply and poor sanitation. Targeting people within a given radius around a cholera case for intervention including vaccination, improved water supply and sanitation may be a practical and effective approach. A ring oral cholera vaccination strategy could be considered before, after or as an alternative to a mass vaccination approach. We review here the use of the ring vaccinations in general and specifically during cholera outbreaks.
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Affiliation(s)
- Jacqueline Deen
- Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines, Manila, Philippines
| | - Lorenz von Seidlein
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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Pasetto D, Finger F, Camacho A, Grandesso F, Cohuet S, Lemaitre JC, Azman AS, Luquero FJ, Bertuzzo E, Rinaldo A. Near real-time forecasting for cholera decision making in Haiti after Hurricane Matthew. PLoS Comput Biol 2018; 14:e1006127. [PMID: 29768401 PMCID: PMC5973636 DOI: 10.1371/journal.pcbi.1006127] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 05/29/2018] [Accepted: 04/09/2018] [Indexed: 12/04/2022] Open
Abstract
Computational models of cholera transmission can provide objective insights into the course of an ongoing epidemic and aid decision making on allocation of health care resources. However, models are typically designed, calibrated and interpreted post-hoc. Here, we report the efforts of a team from academia, field research and humanitarian organizations to model in near real-time the Haitian cholera outbreak after Hurricane Matthew in October 2016, to assess risk and to quantitatively estimate the efficacy of a then ongoing vaccination campaign. A rainfall-driven, spatially-explicit meta-community model of cholera transmission was coupled to a data assimilation scheme for computing short-term projections of the epidemic in near real-time. The model was used to forecast cholera incidence for the months after the passage of the hurricane (October-December 2016) and to predict the impact of a planned oral cholera vaccination campaign. Our first projection, from October 29 to December 31, predicted the highest incidence in the departments of Grande Anse and Sud, accounting for about 45% of the total cases in Haiti. The projection included a second peak in cholera incidence in early December largely driven by heavy rainfall forecasts, confirming the urgency for rapid intervention. A second projection (from November 12 to December 31) used updated rainfall forecasts to estimate that 835 cases would be averted by vaccinations in Grande Anse (90% Prediction Interval [PI] 476-1284) and 995 in Sud (90% PI 508-2043). The experience gained by this modeling effort shows that state-of-the-art computational modeling and data-assimilation methods can produce informative near real-time projections of cholera incidence. Collaboration among modelers and field epidemiologists is indispensable to gain fast access to field data and to translate model results into operational recommendations for emergency management during an outbreak. Future efforts should thus draw together multi-disciplinary teams to ensure model outputs are appropriately based, interpreted and communicated.
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Affiliation(s)
- Damiano Pasetto
- Laboratory of Ecohydrology, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Flavio Finger
- Laboratory of Ecohydrology, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Centre for the Mathematical Modelling of Infectious Diseases, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anton Camacho
- Centre for the Mathematical Modelling of Infectious Diseases, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Epicentre, Paris, France
| | | | | | - Joseph C. Lemaitre
- Laboratory of Ecohydrology, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Andrew S. Azman
- Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Francisco J. Luquero
- Epicentre, Geneva, Switzerland
- Department of International Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Enrico Bertuzzo
- Department of Environmental Sciences, Informatics and Statistics, University Ca’ Foscari Venezia, Venezia Mestre, Italy
| | - Andrea Rinaldo
- Laboratory of Ecohydrology, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Civil, Environmental and Architectural Engineering, University of Padua, Padova, Italy
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Ivers LC. Cholera control: one dose at a time. THE LANCET. INFECTIOUS DISEASES 2018; 18:591-592. [PMID: 29550405 DOI: 10.1016/s1473-3099(18)30170-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 02/20/2018] [Indexed: 10/17/2022]
Affiliation(s)
- Louise C Ivers
- Center for Global Health, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA, USA.
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Al-Mekhlafi HM. Yemen in a Time of Cholera: Current Situation and Challenges. Am J Trop Med Hyg 2018; 98:1558-1562. [PMID: 29557331 DOI: 10.4269/ajtmh.17-0811] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Since early 2015, Yemen has been in the throes of a grueling civil war, which has devastated the health system and public services, and created one of the world's worst humanitarian disasters. The country is currently facing a cholera epidemic the world's largest on record, surpassing one million (1,061,548) suspected cases, with 2,373 related deaths since October 2016. Cases were first confirmed in Sana'a city and then spread to almost all governorates except Socotra Island. Continued efforts are being made by the World Health Organization and international partners to contain the epidemic through improving water, sanitation and hygiene, setting up diarrhea treatment centers, and improving the population's awareness about the disease. The provision of clean water and adequate sanitation is imperative as an effective long-term solution to prevent the further spread of this epidemic. Cholera vaccination campaigns should also be conducted as a preventive measure.
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Affiliation(s)
- Hesham M Al-Mekhlafi
- Medical Research Center, Jazan University, Jazan, Kingdom of Saudi Arabia.,Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
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69
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Qadri F, Ali M, Lynch J, Chowdhury F, Khan AI, Wierzba TF, Excler JL, Saha A, Islam MT, Begum YA, Bhuiyan TR, Khanam F, Chowdhury MI, Khan IA, Kabir A, Riaz BK, Akter A, Khan A, Asaduzzaman M, Kim DR, Siddik AU, Saha NC, Cravioto A, Singh AP, Clemens JD. Efficacy of a single-dose regimen of inactivated whole-cell oral cholera vaccine: results from 2 years of follow-up of a randomised trial. THE LANCET. INFECTIOUS DISEASES 2018; 18:666-674. [PMID: 29550406 DOI: 10.1016/s1473-3099(18)30108-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 01/12/2018] [Accepted: 01/15/2018] [Indexed: 11/24/2022]
Abstract
BACKGROUND A single-dose regimen of inactivated whole-cell oral cholera vaccine (OCV) is attractive because it reduces logistical challenges for vaccination and could enable more people to be vaccinated. Previously, we reported the efficacy of a single dose of an OCV vaccine during the 6 months following dosing. Herein, we report the results of 2 years of follow-up. METHODS In this placebo-controlled, double-blind trial done in Dhaka, Bangladesh, individuals aged 1 year or older with no history of receipt of OCV were randomly assigned to receive a single dose of inactivated OCV or oral placebo. The primary endpoint was a confirmed episode of non-bloody diarrhoea for which the onset was at least 7 days after dosing and a faecal culture was positive for Vibrio cholerae O1 or O139. Passive surveillance for diarrhoea was done in 13 hospitals or major clinics located in or near the study area for 2 years after the last administered dose. We assessed the protective efficacy of the OCV against culture-confirmed cholera occurring 7-730 days after dosing with both crude and multivariable per-protocol analyses. This trial is registered at ClinicalTrials.gov, number NCT02027207. FINDINGS Between Jan 10, 2014, and Feb 4, 2014, 205 513 people were randomly assigned to receive either vaccine or placebo, of whom 204 700 (102 552 vaccine recipients and 102 148 placebo recipients) were included in the per-protocol analysis. 287 first episodes of cholera (109 among vaccine recipients and 178 among placebo recipients) were detected during the 2-year follow-up; 138 of these episodes (46 in vaccine recipients and 92 in placebo recipients) were associated with severe dehydration. The overall incidence rates of initial cholera episodes were 0·22 (95% CI 0·18 to 0·27) per 100 000 person-days in vaccine recipients versus 0·36 (0·31 to 0·42) per 100 000 person-days in placebo recipients (adjusted protective efficacy 39%, 95% CI 23 to 52). The overall incidence of severe cholera was 0·09 (0·07 to 0·12) per 100 000 person-days versus 0·19 (0·15 to 0·23; adjusted protective efficacy 50%, 29 to 65). Vaccine protective efficacy was 52% (8 to 75) against all cholera episodes and 71% (27 to 88) against severe cholera episodes in participants aged 5 years to younger than 15 years. For participants aged 15 years or older, vaccine protective efficacy was 59% (42 to 71) against all cholera episodes and 59% (35 to 74) against severe cholera. The protection in the older age groups was sustained throughout the 2-year follow-up. In participants younger than 5 years, the vaccine did not show protection against either all cholera episodes (protective efficacy -13%, -68 to 25) or severe cholera episodes (-44%, -220 to 35). INTERPRETATION A single dose of the inactivated whole-cell OCV offered protection to older children and adults that was sustained for at least 2 years. The absence of protection of young children might reflect a lesser degree of pre-existing natural immunity in this age group. FUNDING Bill & Melinda Gates Foundation to the International Vaccine Institute.
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Affiliation(s)
- Firdausi Qadri
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh.
| | - Mohammad Ali
- Department of International Health, Johns Hopkins School of Public Health, Baltimore, MD, USA
| | - Julia Lynch
- International Vaccine Institute, Seoul, South Korea
| | - Fahima Chowdhury
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Ashraful Islam Khan
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | | | | | - Amit Saha
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Md Taufiqul Islam
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Yasmin A Begum
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Taufiqur R Bhuiyan
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Farhana Khanam
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Mohiul I Chowdhury
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Iqbal Ansary Khan
- The Institute of Epidemiology, Disease Control and Research, Dhaka, Bangladesh
| | - Alamgir Kabir
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Baizid Khoorshid Riaz
- Department of Public Health and Hospital Administration, National Institute of Preventive and Social Medicine, Dhaka, Bangladesh
| | - Afroza Akter
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Arifuzzaman Khan
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Muhammad Asaduzzaman
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | | | - Ashraf U Siddik
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Nirod C Saha
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | - Alejandro Cravioto
- Department of Public Health, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico
| | - Ajit P Singh
- MSD Wellcome Trust Hilleman Laboratories, New Delhi, India
| | - John D Clemens
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh; Department of Epidemiology of the Center for Global Infectious Diseases, UCLA Fielding School of Public Health, Los Angeles, CA, USA; Department of Medicine, Korea University School of Medicine, Seoul, South Korea
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70
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Ferreras E, Chizema-Kawesha E, Blake A, Chewe O, Mwaba J, Zulu G, Poncin M, Rakesh A, Page AL, Stoitsova S, Voute C, Uzzeni F, Robert H, Serafini M, Matapo B, Eiros JM, Quilici ML, Pezzoli L, Azman AS, Cohuet S, Ciglenecki I, Malama K, Luquero FJ. Single-Dose Cholera Vaccine in Response to an Outbreak in Zambia. N Engl J Med 2018; 378:577-579. [PMID: 29414267 DOI: 10.1056/nejmc1711583] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
| | | | | | | | - John Mwaba
- University Teaching Hospital, Lusaka, Zambia
| | | | - Marc Poncin
- Médecins sans Frontières, Geneva, Switzerland
| | | | | | - Savina Stoitsova
- European Program for Intervention Epidemiology Training, Stockholm, Sweden
| | | | | | | | | | | | | | | | | | - Andrew S Azman
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
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71
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Finger F, Bertuzzo E, Luquero FJ, Naibei N, Touré B, Allan M, Porten K, Lessler J, Rinaldo A, Azman AS. The potential impact of case-area targeted interventions in response to cholera outbreaks: A modeling study. PLoS Med 2018; 15:e1002509. [PMID: 29485987 PMCID: PMC5828347 DOI: 10.1371/journal.pmed.1002509] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 01/19/2018] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Cholera prevention and control interventions targeted to neighbors of cholera cases (case-area targeted interventions [CATIs]), including improved water, sanitation, and hygiene, oral cholera vaccine (OCV), and prophylactic antibiotics, may be able to efficiently avert cholera cases and deaths while saving scarce resources during epidemics. Efforts to quickly target interventions to neighbors of cases have been made in recent outbreaks, but little empirical evidence related to the effectiveness, efficiency, or ideal design of this approach exists. Here, we aim to provide practical guidance on how CATIs might be used by exploring key determinants of intervention impact, including the mix of interventions, "ring" size, and timing, in simulated cholera epidemics fit to data from an urban cholera epidemic in Africa. METHODS AND FINDINGS We developed a micro-simulation model and calibrated it to both the epidemic curve and the small-scale spatiotemporal clustering pattern of case households from a large 2011 cholera outbreak in N'Djamena, Chad (4,352 reported cases over 232 days), and explored the potential impact of CATIs in simulated epidemics. CATIs were implemented with realistic logistical delays after cases presented for care using different combinations of prophylactic antibiotics, OCV, and/or point-of-use water treatment (POUWT) starting at different points during the epidemics and targeting rings of various radii around incident case households. Our findings suggest that CATIs shorten the duration of epidemics and are more resource-efficient than mass campaigns. OCV was predicted to be the most effective single intervention, followed by POUWT and antibiotics. CATIs with OCV started early in an epidemic focusing on a 100-m radius around case households were estimated to shorten epidemics by 68% (IQR 62% to 72%), with an 81% (IQR 69% to 87%) reduction in cases compared to uncontrolled epidemics. These same targeted interventions with OCV led to a 44-fold (IQR 27 to 78) reduction in the number of people needed to target to avert a single case of cholera, compared to mass campaigns in high-cholera-risk neighborhoods. The optimal radius to target around incident case households differed by intervention type, with antibiotics having an optimal radius of 30 m to 45 m compared to 70 m to 100 m for OCV and POUWT. Adding POUWT or antibiotics to OCV provided only marginal impact and efficiency improvements. Starting CATIs early in an epidemic with OCV and POUWT targeting those within 100 m of an incident case household reduced epidemic durations by 70% (IQR 65% to 75%) and the number of cases by 82% (IQR 71% to 88%) compared to uncontrolled epidemics. CATIs used late in epidemics, even after the peak, were estimated to avert relatively few cases but substantially reduced the number of epidemic days (e.g., by 28% [IQR 15% to 45%] for OCV in a 100-m radius). While this study is based on a rigorous, data-driven approach, the relatively high uncertainty about the ways in which POUWT and antibiotic interventions reduce cholera risk, as well as the heterogeneity in outbreak dynamics from place to place, limits the precision and generalizability of our quantitative estimates. CONCLUSIONS In this study, we found that CATIs using OCV, antibiotics, and water treatment interventions at an appropriate radius around cases could be an effective and efficient way to fight cholera epidemics. They can provide a complementary and efficient approach to mass intervention campaigns and may prove particularly useful during the initial phase of an outbreak, when there are few cases and few available resources, or in order to shorten the often protracted tails of cholera epidemics.
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Affiliation(s)
- Flavio Finger
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Enrico Bertuzzo
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Dipartimento di Scienze Ambientali, Informatica e Statistica, Università Ca’ Foscari Venezia, Venice, Italy
| | - Francisco J. Luquero
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Epicentre, Paris, France
| | - Nathan Naibei
- Communauté des Amis de l’Informatique pour le Développement–Tchad, N’Djamena, Chad
| | | | | | | | - Justin Lessler
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Andrea Rinaldo
- Laboratory of Ecohydrology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Dipartimento di Ingegneria Civile, Edile ed Ambientale, Università di Padova, Padova, Italy
| | - Andrew S. Azman
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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A Quantitative Systematic Review and Meta-Analysis of the Effectiveness of Oral Cholera Vaccine as a Reactive Measure in Cholera Outbreaks. Prehosp Disaster Med 2018; 33:2-6. [PMID: 29317005 DOI: 10.1017/s1049023x17007166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Introduction The efficacy of oral cholera vaccines (OCVs) in laboratory conditions has been established, and the World Health Organization (WHO; Geneva, Switzerland) has recommended their preventative use in high-risk settings. The WHO recommendation has not been fully operationalized, nor has it been extended to apply to the reactive use of OCVs in real field epidemic conditions due to concerns about potential resource diversion, feasibility, cost, and acceptability. The purpose of this study is to assess and synthesize existing evidence of OCV effectiveness when used reactively in real field conditions. METHODS A systematic review and meta-analysis was conducted involving studies that investigated vaccine effectiveness when used as a reactive measure; that is, cases had reached epidemic threshold and a cholera epidemic was declared in real field epidemic conditions. OVID Medline (US National Library of Medicine, National Institutes of Health; Bethesda, Maryland USA), CINAHL (EBSCO Information Services; Ipswich, Massachusetts USA), and EMBASE (Elsevier; Amsterdam, Netherlands), along with grey literature, were systematically searched using pre-determined criteria. Two independent reviewers identified studies that met the selection criteria and data were extracted using validated tools. Pooled estimates were obtained using fixed effect models. RESULTS Of the 347 articles that met the inclusion criteria, four studies were retrieved for meta-analysis (three were case-control studies and one was a case-cohort study) involving a total of 1,509 participants and comprising 175 cases and 1,334 case controls. The effectiveness of one or two doses of either Shanchol (Shantha Biotechnics; India) or ORC-Vax (Vabiotech; Vietnam) OCVs showed a combined vaccine effectiveness of 75% (95% CI, 61-84). CONCLUSION A positive association was demonstrated between the reactive use of OCVs and protection against cholera. This supported the WHO recommendation to utilize OCVs reactively as an additional measure to the standard cholera epidemic response package. Schwerdtle P , Onekon CK , Recoche K . A quantitative systematic review and meta-analysis of the effectiveness of oral cholera vaccine as a reactive measure in cholera outbreaks. Prehosp Disaster Med. 2018;33(1):2-6.
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Poncin M, Zulu G, Voute C, Ferreras E, Muleya CM, Malama K, Pezzoli L, Mufunda J, Robert H, Uzzeni F, Luquero FJ, Chizema E, Ciglenecki I. Implementation research: reactive mass vaccination with single-dose oral cholera vaccine, Zambia. Bull World Health Organ 2017; 96:86-93. [PMID: 29403111 PMCID: PMC5791774 DOI: 10.2471/blt.16.189241] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 09/30/2017] [Accepted: 10/02/2017] [Indexed: 12/19/2022] Open
Abstract
Objective To describe the implementation and feasibility of an innovative mass vaccination strategy – based on single-dose oral cholera vaccine – to curb a cholera epidemic in a large urban setting. Method In April 2016, in the early stages of a cholera outbreak in Lusaka, Zambia, the health ministry collaborated with Médecins Sans Frontières and the World Health Organization in organizing a mass vaccination campaign, based on single-dose oral cholera vaccine. Over a period of 17 days, partners mobilized 1700 health ministry staff and community volunteers for community sensitization, social mobilization and vaccination activities in 10 townships. On each day, doses of vaccine were delivered to vaccination sites and administrative coverage was estimated. Findings Overall, vaccination teams administered 424 100 doses of vaccine to an estimated target population of 578 043, resulting in an estimated administrative coverage of 73.4%. After the campaign, few cholera cases were reported and there was no evidence of the disease spreading within the vaccinated areas. The total cost of the campaign – 2.31 United States dollars (US$) per dose – included the relatively low cost of local delivery – US$ 0.41 per dose. Conclusion We found that an early and large-scale targeted reactive campaign using a single-dose oral vaccine, organized in response to a cholera epidemic within a large city, to be feasible and appeared effective. While cholera vaccines remain in short supply, the maximization of the number of vaccines in response to a cholera epidemic, by the use of just one dose per member of an at-risk community, should be considered.
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Affiliation(s)
- Marc Poncin
- Médecins sans Frontières, 78, rue de Lausanne, Case Postale 1016, 1211 Geneva, Switzerland
| | - Gideon Zulu
- Republic of Zambia Ministry of Health, Lusaka, Zambia
| | - Caroline Voute
- Médecins sans Frontières, 78, rue de Lausanne, Case Postale 1016, 1211 Geneva, Switzerland
| | | | | | | | | | | | - Hugues Robert
- Médecins sans Frontières, 78, rue de Lausanne, Case Postale 1016, 1211 Geneva, Switzerland
| | - Florent Uzzeni
- Médecins sans Frontières, 78, rue de Lausanne, Case Postale 1016, 1211 Geneva, Switzerland
| | | | | | - Iza Ciglenecki
- Médecins sans Frontières, 78, rue de Lausanne, Case Postale 1016, 1211 Geneva, Switzerland
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74
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Franke MF, Jerome JG, Matias WR, Ternier R, Hilaire IJ, Harris JB, Ivers LC. Comparison of two control groups for estimation of oral cholera vaccine effectiveness using a case-control study design. Vaccine 2017; 35:5819-5827. [PMID: 28916247 DOI: 10.1016/j.vaccine.2017.09.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Case-control studies to quantify oral cholera vaccine effectiveness (VE) often rely on neighbors without diarrhea as community controls. Test-negative controls can be easily recruited and may minimize bias due to differential health-seeking behavior and recall. We compared VE estimates derived from community and test-negative controls and conducted bias-indicator analyses to assess potential bias with community controls. METHODS From October 2012 through November 2016, patients with acute watery diarrhea were recruited from cholera treatment centers in rural Haiti. Cholera cases had a positive stool culture. Non-cholera diarrhea cases (test-negative controls and non-cholera diarrhea cases for bias-indicator analyses) had a negative culture and rapid test. Up to four community controls were matched to diarrhea cases by age group, time, and neighborhood. RESULTS Primary analyses included 181 cholera cases, 157 non-cholera diarrhea cases, 716 VE community controls and 625 bias-indicator community controls. VE for self-reported vaccination with two doses was consistent across the two control groups, with statistically significant VE estimates ranging from 72 to 74%. Sensitivity analyses revealed similar, though somewhat attenuated estimates for self-reported two dose VE. Bias-indicator estimates were consistently less than one, with VE estimates ranging from 19 to 43%, some of which were statistically significant. CONCLUSIONS OCV estimates from case-control analyses using community and test-negative controls were similar. While bias-indicator analyses suggested possible over-estimation of VE estimates using community controls, test-negative analyses suggested this bias, if present, was minimal. Test-negative controls can be a valid low-cost and time-efficient alternative to community controls for OCV effectiveness estimation and may be especially relevant in emergency situations.
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Affiliation(s)
- Molly F Franke
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA, USA.
| | | | - Wilfredo R Matias
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA, USA
| | - Ralph Ternier
- Zanmi Lasante/Partners In Health, Port au Prince, Haiti
| | | | - Jason B Harris
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
| | - Louise C Ivers
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA, USA; Division of Global Health Equity, Brigham and Women's Hospital, Boston, MA, USA
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Bioley G, Monnerat J, Lötscher M, Vonarburg C, Zuercher A, Corthésy B. Plasma-Derived Polyreactive Secretory-Like IgA and IgM Opsonizing Salmonella enterica Typhimurium Reduces Invasion and Gut Tissue Inflammation through Agglutination. Front Immunol 2017; 8:1043. [PMID: 28900429 PMCID: PMC5581814 DOI: 10.3389/fimmu.2017.01043] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 08/11/2017] [Indexed: 12/27/2022] Open
Abstract
Due to the increasing emergence of antibiotic-resistant strains of enteropathogenic bacteria, development of alternative treatments to fight against gut infections is a major health issue. While vaccination requires that a proper combination of antigen, adjuvant, and delivery route is defined to elicit protective immunity at mucosae, oral delivery of directly active antibody preparations, referred to as passive immunization, sounds like a valuable alternative. Along the gut, the strategy suffers, however, from the difficulty to obtain sufficient amounts of antibodies with the appropriate specificity and molecular structure for mucosal delivery. Physiologically, at the antibody level, the protection of gastrointestinal mucosal surfaces against enteropathogens is principally mediated by secretory IgA and secretory IgM. We previously demonstrated that purified human plasma-derived IgA and IgM can be associated with secretory component to generate biologically active secretory-like IgA and IgM (SCIgA/M) that can protect epithelial cells from infection by Shigella flexneri in vitro. In this study, we aimed at evaluating the protective potential of these antibody preparations in vivo. We now establish that such polyreactive preparations bind efficiently to Salmonella enterica Typhimurium and trigger bacterial agglutination, as observed by laser scanning confocal microscopy. Upon delivery into a mouse ligated intestinal loop, SCIgA/M-mediated aggregates persist in the intestinal environment and limit the entry of bacteria into intestinal Peyer’s patches via immune exclusion. Moreover, oral administration to mice of immune complexes composed of S. Typhimurium and SCIgA/M reduces mucosal infection, systemic dissemination, and local inflammation. Altogether, our data provide valuable clues for the future appraisal of passive oral administration of polyreactive plasma-derived SCIgA/M to combat infection by a variety of enteropathogens.
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Affiliation(s)
- Gilles Bioley
- R&D Laboratory, Division of Immunology and Allergy, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Justine Monnerat
- R&D Laboratory, Division of Immunology and Allergy, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | | | | | | | - Blaise Corthésy
- R&D Laboratory, Division of Immunology and Allergy, Lausanne University Hospital (CHUV), Lausanne, Switzerland
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Oral cholera vaccine coverage in hard-to-reach fishermen communities after two mass Campaigns, Malawi, 2016. Vaccine 2017; 35:5194-5200. [PMID: 28803712 PMCID: PMC5594244 DOI: 10.1016/j.vaccine.2017.07.104] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 07/25/2017] [Accepted: 07/27/2017] [Indexed: 12/18/2022]
Abstract
Simplified delivery strategies were proposed in hard-to-reach population. High full coverage was reached in the most at-risk individuals. Vaccines use efficiency need to be improved.
Context From December 2015 to August 2016, a large epidemic of cholera affected the fishermen of Lake Chilwa in Malawi. A first reactive Oral Cholera Vaccines (OCV) campaign was organized, in February, in a 2 km radius of the lake followed by a preemptive one, conducted in November, in a 25 km radius. We present the vaccine coverage reached in hard-to-reach population using simplified delivery strategies. Method We conducted two-stage random-sampling cross-sectional surveys among individuals living in a 2 km and 25 km radius of Lake Chilwa (islands and floating homes included). Individuals aged 12 months and older from Machinga and Zomba districts were sampled: 43 clusters of 14 households were surveyed. Simplified strategies were used for those living in islands and floating homes: self- delivery and community-supervised delivery of the second dose. Vaccine coverage (VC) for at-least-two-doses was estimated taking into account sampling weights and design effects. Results A total of 1176 households were surveyed (2.7% of non-response). Among the 2833 individuals living in the 2 km radius of Lake and the 2915 in the 25 km radius: 457 (16.1%) and 239 (8.2%) lived in floating homes or on islands at some point in the year, respectively. For the overall population, VC was 75.6% and 54.2%, respectively. In the 2 km radius, VC was 92.2% for those living on the lake at some point of the year: 271 (64.8%) used the simplified strategies. The main reasons for non-vaccination were absence during the campaign and vaccine shortage. Few adverse events occurring in the 24 h following vaccination was reported. Conclusions We reached a high two-dose coverage of the most at-risk population using simplified delivery strategies. Because of the high fishermen mobility, regular catch-up campaigns or another strategy specifically targeting fishermen need to be assessed for more efficient vaccines use.
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Kanungo S, Chatterjee P. Oral cholera vaccines: exploring the farrago of evidence. THE LANCET. INFECTIOUS DISEASES 2017; 17:1012-1013. [PMID: 28729166 DOI: 10.1016/s1473-3099(17)30420-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 06/20/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Suman Kanungo
- Indian Council of Medical Research, National Institute of Cholera and Enteric Diseases, Kolkata 700010, India.
| | - Pranab Chatterjee
- Indian Council of Medical Research, National Institute of Cholera and Enteric Diseases, Kolkata 700010, India
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Bi Q, Ferreras E, Pezzoli L, Legros D, Ivers LC, Date K, Qadri F, Digilio L, Sack DA, Ali M, Lessler J, Luquero FJ, Azman AS. Protection against cholera from killed whole-cell oral cholera vaccines: a systematic review and meta-analysis. THE LANCET. INFECTIOUS DISEASES 2017; 17:1080-1088. [PMID: 28729167 PMCID: PMC5639147 DOI: 10.1016/s1473-3099(17)30359-6] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 05/06/2017] [Accepted: 05/30/2017] [Indexed: 11/01/2022]
Abstract
BACKGROUND Killed whole-cell oral cholera vaccines (kOCVs) are becoming a standard cholera control and prevention tool. However, vaccine efficacy and direct effectiveness estimates have varied, with differences in study design, location, follow-up duration, and vaccine composition posing challenges for public health decision making. We did a systematic review and meta-analysis to generate average estimates of kOCV efficacy and direct effectiveness from the available literature. METHODS For this systematic review and meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Review Library on July 9, 2016, and ISI Web of Science on July 11, 2016, for randomised controlled trials and observational studies that reported estimates of direct protection against medically attended confirmed cholera conferred by kOCVs. We included studies published on any date in English, Spanish, French, or Chinese. We extracted from the published reports the primary efficacy and effectiveness estimates from each study and also estimates according to number of vaccine doses, duration, and age group. The main study outcome was average efficacy and direct effectiveness of two kOCV doses, which we estimated with random-effect models. This study is registered with PROSPERO, number CRD42016048232. FINDINGS Seven trials (with 695 patients with cholera) and six observational studies (217 patients with cholera) met the inclusion criteria, with an average two-dose efficacy of 58% (95% CI 42-69, I2=58%) and effectiveness of 76% (62-85, I2=0). Average two-dose efficacy in children younger than 5 years (30% [95% CI 15-42], I2=0%) was lower than in those 5 years or older (64% [58-70], I2=0%; p<0·0001). Two-dose efficacy estimates of kOCV were similar during the first 2 years after vaccination, with estimates of 56% (95% CI 42-66, I2=45%) in the first year and 59% (49-67, I2=0) in the second year. The efficacy reduced to 39% (13 to 57, I2=48%) in the third year, and 26% (-46 to 63, I2=74%) in the fourth year. INTERPRETATION Two kOCV doses provide protection against cholera for at least 3 years. One kOCV dose provides at least short-term protection, which has important implications for outbreak management. kOCVs are effective tools for cholera control. FUNDING The Bill & Melinda Gates Foundation.
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Affiliation(s)
- Qifang Bi
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Eva Ferreras
- Environmental and Cancer Epidemiology Unit, National Centre for Epidemiology, Carlos III Institute of Health, Madrid, Spain; Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), Carlos III Institute of Health, Madrid, Spain
| | | | | | - Louise C Ivers
- Department of Medicine, Division of Global Health Equity, Brigham and Women's Hospital, Boston, MA, USA; Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA, USA
| | - Kashmira Date
- United States Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka, Bangladesh
| | | | - David A Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Mohammad Ali
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Justin Lessler
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Francisco J Luquero
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Epicentre, Paris, France
| | - Andrew S Azman
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Médecins Sans Frontières, Geneva, Switzerland.
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Parker LA, Rumunu J, Jamet C, Kenyi Y, Lino RL, Wamala JF, Mpairwe AM, Muller V, Llosa AE, Uzzeni F, Luquero FJ, Ciglenecki I, Azman AS. Neighborhood-targeted and case-triggered use of a single dose of oral cholera vaccine in an urban setting: Feasibility and vaccine coverage. PLoS Negl Trop Dis 2017; 11:e0005652. [PMID: 28594891 PMCID: PMC5478158 DOI: 10.1371/journal.pntd.0005652] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 06/20/2017] [Accepted: 05/19/2017] [Indexed: 02/02/2023] Open
Abstract
INTRODUCTION In June 2015, a cholera outbreak was declared in Juba, South Sudan. In addition to standard outbreak control measures, oral cholera vaccine (OCV) was proposed. As sufficient doses to cover the at-risk population were unavailable, a campaign using half the standard dosing regimen (one-dose) targeted high-risk neighborhoods and groups including neighbors of suspected cases. Here we report the operational details of this first public health use of a single-dose regimen of OCV and illustrate the feasibility of conducting highly targeted vaccination campaigns in an urban area. METHODOLOGY/PRINCIPAL FINDINGS Neighborhoods of the city were prioritized for vaccination based on cumulative attack rates, active transmission and local knowledge of known cholera risk factors. OCV was offered to all persons older than 12 months at 20 fixed sites and to select groups, including neighbors of cholera cases after the main campaign ('case-triggered' interventions), through mobile teams. Vaccination coverage was estimated by multi-stage surveys using spatial sampling techniques. 162,377 individuals received a single-dose of OCV in the targeted neighborhoods. In these neighborhoods vaccine coverage was 68.8% (95% Confidence Interval (CI), 64.0-73.7) and was highest among children ages 5-14 years (90.0%, 95% CI 85.7-94.3), with adult men being less likely to be vaccinated than adult women (Relative Risk 0.81, 95% CI: 0.68-0.96). In the case-triggered interventions, each lasting 1-2 days, coverage varied (range: 30-87%) with an average of 51.0% (95% CI 41.7-60.3). CONCLUSIONS/SIGNIFICANCE Vaccine supply constraints and the complex realities where cholera outbreaks occur may warrant the use of flexible alternative vaccination strategies, including highly-targeted vaccination campaigns and single-dose regimens. We showed that such campaigns are feasible. Additional work is needed to understand how and when to use different strategies to best protect populations against epidemic cholera.
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Affiliation(s)
- Lucy A. Parker
- Médecins Sans Frontières, Geneva, Switzerland
- CIBER Epidemiología y Salud Pública, Department of Public Health, Universidad Miguel Hernández, Alicante, Spain
| | - John Rumunu
- Republic of South Sudan Ministry of Health, Juba, South Sudan
| | | | - Yona Kenyi
- Republic of South Sudan Ministry of Health, Juba, South Sudan
| | | | | | | | | | | | | | - Francisco J. Luquero
- Epicentre, Paris, France
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | | | - Andrew S. Azman
- Médecins Sans Frontières, Geneva, Switzerland
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
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Vaccines plus water, sanitation, and hygiene interventions in the fight against cholera – Authors' reply. THE LANCET GLOBAL HEALTH 2017; 5:e395. [DOI: 10.1016/s2214-109x(17)30086-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 12/14/2016] [Indexed: 11/24/2022] Open
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Adapting to the global shortage of cholera vaccines: targeted single dose cholera vaccine in response to an outbreak in South Sudan. THE LANCET. INFECTIOUS DISEASES 2017; 17:e123-e127. [PMID: 28109819 DOI: 10.1016/s1473-3099(16)30472-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 09/26/2016] [Accepted: 10/07/2016] [Indexed: 02/02/2023]
Abstract
Shortages of vaccines for epidemic diseases, such as cholera, meningitis, and yellow fever, have become common over the past decade, hampering efforts to control outbreaks through mass reactive vaccination campaigns. Additionally, various epidemiological, political, and logistical challenges, which are poorly documented in the literature, often lead to delays in reactive campaigns, ultimately reducing the effect of vaccination. In June 2015, a cholera outbreak occurred in Juba, South Sudan, and because of the global shortage of oral cholera vaccine, authorities were unable to secure sufficient doses to vaccinate the entire at-risk population-approximately 1 million people. In this Personal View, we document the first public health use of a reduced, single-dose regimen of oral cholera vaccine, and show the details of the decision-making process and timeline. We also make recommendations to help improve reactive vaccination campaigns against cholera, and discuss the importance of new and flexible context-specific dose regimens and vaccination strategies.
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Ontweka LN, Deng LO, Rauzier J, Debes AK, Tadesse F, Parker LA, Wamala JF, Bior BK, Lasuba M, But AB, Grandesso F, Jamet C, Cohuet S, Ciglenecki I, Serafini M, Sack DA, Quilici ML, Azman AS, Luquero FJ, Page AL. Cholera Rapid Test with Enrichment Step Has Diagnostic Performance Equivalent to Culture. PLoS One 2016; 11:e0168257. [PMID: 27992488 PMCID: PMC5167375 DOI: 10.1371/journal.pone.0168257] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 11/28/2016] [Indexed: 11/21/2022] Open
Abstract
Cholera rapid diagnostic tests (RDT) could play a central role in outbreak detection and surveillance in low-resource settings, but their modest performance has hindered their broad adoption. The addition of an enrichment step may improve test specificity. We describe the results of a prospective diagnostic evaluation of the Crystal VC RDT (Span Diagnostics, India) with enrichment step and of culture, each compared to polymerase chain reaction (PCR), during a cholera outbreak in South Sudan. RDTs were performed on alkaline peptone water inoculated with stool and incubated for 4–6 hours at ambient temperature. Cholera culture was performed from wet filter paper inoculated with stool. Molecular detection of Vibrio cholerae O1 by PCR was done from dry Whatman 903 filter papers inoculated with stool, and from wet filter paper supernatant. In August and September 2015, 101 consecutive suspected cholera cases were enrolled, of which 36 were confirmed by PCR. The enriched RDT had 86.1% (95% CI: 70.5–95.3) sensitivity and 100% (95% CI: 94.4–100) specificity compared to PCR as the reference standard. The sensitivity of culture versus PCR was 83.3% (95% CI: 67.2–93.6) for culture performed on site and 72.2% (95% CI: 54.8–85.8) at the international reference laboratory, where samples were tested after an average delay of two months after sample collection, and specificity was 98.5% (95% CI: 91.7–100) and 100% (95% CI: 94.5–100), respectively. The RDT with enrichment showed performance comparable to that of culture and could be a sustainable alternative to culture confirmation where laboratory capacity is limited.
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Affiliation(s)
- Lameck N. Ontweka
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
- Amref Health Africa Headquarters, Nairobi, Kenya
| | - Lul O. Deng
- National Public Health Laboratory, Ministry of Health, Juba, South Sudan
| | - Jean Rauzier
- Enteric Bacterial Pathogens Unit, National Reference Centre for Vibrios and Cholera, Institut Pasteur, Paris, France
| | - Amanda K. Debes
- Department of International Health, Johns Hopkins University, Baltimore, United States of America
| | | | - Lucy A. Parker
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
| | | | - Bior K. Bior
- National Public Health Laboratory, Ministry of Health, Juba, South Sudan
| | - Michael Lasuba
- National Public Health Laboratory, Ministry of Health, Juba, South Sudan
| | - Abiem Bona But
- National Public Health Laboratory, Ministry of Health, Juba, South Sudan
| | | | - Christine Jamet
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
| | | | - Iza Ciglenecki
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
| | - Micaela Serafini
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
| | - David A. Sack
- Department of International Health, Johns Hopkins University, Baltimore, United States of America
| | - Marie-Laure Quilici
- Enteric Bacterial Pathogens Unit, National Reference Centre for Vibrios and Cholera, Institut Pasteur, Paris, France
| | - Andrew S. Azman
- Médecins Sans Frontières Operational Center Geneva, Geneva, Switzerland
- Department of Epidemiology, Johns Hopkins University, Baltimore, United States of America
| | - Francisco J. Luquero
- Department of International Health, Johns Hopkins University, Baltimore, United States of America
- Field epidemiology, Epicentre, Paris, France
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Ivers LC. New strategies for cholera control. THE LANCET GLOBAL HEALTH 2016; 4:e771-e772. [DOI: 10.1016/s2214-109x(16)30257-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 09/06/2016] [Indexed: 10/20/2022] Open
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