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Cholera is now considered to be endemic in Haiti, often with increased incidence during rainy seasons. The challenge of cholera surveillance is exacerbated by the cost of sample collection and laboratory analysis. A diagnostic tool is needed that is low cost, easy-to-use, and able to detect and quantify Vibrio cholerae accurately in water samples within 18–24 h, and perform reliably in remote settings lacking laboratory infrastructure and skilled staff. The two main objectives of this study were to develop and evaluate a new culture medium embedded in a new diagnostic tool (PAD for paper based analytical device) for detecting Vibrio cholerae from water samples collected in Haiti. The intent is to provide guidance for corrective action, such as chlorination, for water positive for V. cholerae epidemic strains. For detecting Vibrio cholerae , a new chromogenic medium was designed and evaluated as an alternative to thiosulfate citrate bile salts sucrose (TCBS) agar for testing raw water samples. Sensitivity and specificity of the medium were assessed using both raw and spiked water samples. The Vibrio cholerae chromogenic medium was proved to be highly selective against most of the cultivable bacteria in the water samples, without loss of sensitivity in detection of V. cholerae. Thus, reliability of this new culture medium for detection of V. cholerae in the presence of other Vibrio species in water samples offers a significant advantage. A new paper based device containing the new chromogenic medium previously evaluated was compared with reference methods for detecting V. cholerae from spiked water sample. The microbiological PAD specifications were evaluated in Haiti. More precisely, a total of 185 water samples were collected at five sites in Haiti, June 2014 and again in June 2015. With this new tool, three V. cholerae O1 and 17 V. cholerae non-O1/O139 strains were isolated. The presence of virulence-associated and regulatory genes, including ctx A, zot , ace , and toxR , was confirmed using multiplex PCR. The three V. cholerae O1 isolates were positive for three of the four virulence-associated and regulatory genes. Twelve of the V. cholerae non-O1/O139 isolates were found to carry toxR , but none were ctxA +, zot +, or ace +. However, six of the V. cholerae non-O1/O139 isolates were resistant to penicillin, ampicillin, trimethoprim/sulfamethoxazole, nalidixic acid, and ciprofloxacin. The paper based analytical device (PAD) provides advantages in that standard culture methods employing agar plates are not required. Also, intermediary isolation steps were not required, including transfer to selective growth media, hence these steps being omitted reduced time to results. Furthermore, experienced technical skills also were not required. Thus, PAD is well suited for resource-limited settings. [ABSTRACT FROM AUTHOR]

Background: In mass vaccination campaigns, large volumes of data must be managed efficiently and accurately. In a reactive oral cholera vaccination (OCV) campaign in rural Haiti during an ongoing epidemic, we used a mobile health (mHealth) system to manage data on 50,000 participants in two isolated communities. Methods: Data were collected using 7-inch tablets. Teams pre-registered and distributed vaccine cards with unique barcodes to vaccine-eligible residents during a census in February 2012. First stored on devices, data were uploaded nightly via Wi-fi to a web-hosted database. During the vaccination campaign between April and June 2012, residents presented their cards at vaccination posts and their barcodes were scanned. Vaccinee data from the census were pre-loaded on tablets to autopopulate the electronic form. Nightly analysis of the day's community coverage informed the following day's vaccination strategy. We generated case-finding reports allowing us to identify those who had not yet been vaccinated. Results: During 40 days of vaccination, we collected approximately 1.9 million pieces of data. A total of 45,417 people received at least one OCV dose; of those, 90.8% were documented to have received 2 doses. Though mHealth required up-front financial investment and training, it reduced the need for paper registries and manual data entry, which would have been costly, time-consuming, and is known to increase error. Using Global Positioning System coordinates, we mapped vaccine posts, population size, and vaccine coverage to understand the reach of the campaign. The hardware and software were usable by high school-educated staff. Conclusion: The use of mHealth technology in an OCV campaign in rural Haiti allowed timely creation of an electronic registry with population-level census data, and a targeted vaccination strategy in a dispersed rural population receiving a two-dose vaccine regimen. The use of mHealth should be strongly considered in mass vaccination campaigns in future initiatives. Author Summary: The World Health Organization (WHO) recently endorsed the creation of a global oral cholera vaccine (OCV) stockpile as part of an integrated, strategic framework to address the re-emerging threat that cholera causes worldwide. In conjunction, the WHO also called for continued monitoring and evaluation around the use of OCV in different settings. In response to the cholera epidemic in Haiti that began in October 2010, Partners In Health, an implementing partner of Haiti's Ministry of Health, vaccinated 50,000 Haitians in two rural communities in the Artibonite Valley in 2012. In this paper, the authors describe the use of mobile health (mHealth) technology for data collection and geospatial mapping to document this rural OCV campaign, focusing on the utility, benefits, and challenges of mHealth in a reactive campaign in the midst of the ongoing epidemic. [ABSTRACT FROM AUTHOR]

Cholera is a waterborne disease that continues to pose serious public health problems in many developing countries. Increasing water and sanitation coverage is a goal for local authorities in these countries, as it can eliminate one of the root causes of cholera transmission. The SIWDR (susceptible–infected–water–dumpsite–recovered) model is proposed here to evaluate the effects of the improved coverage of water and sanitation services in a community at risk of a cholera outbreak. This paper provides a mathematical study of the dynamics of the water and sanitation (WatSan) deficits and their public health impact in a community. The theoretical analysis of the SIWDR model gave a certain threshold value (known as the basic reproductive number and denoted R 0 ) to stop the transmission of cholera. It was found that the disease-free equilibrium was globally asymptotically stable whenever R 0 ≤ 1 . The unique endemic equilibrium was globally asymptotically stable whenever R 0 > 1 . Sensitivity analysis was performed to determine the relative importance of model parameters to disease transmission and prevention. The numerical simulation results, using realistic parameter values in describing cholera transmission in Haiti, showed that improving the drinking water supply, wastewater and sewage treatment, and solid waste disposal services would be effective strategies for controlling the transmission pathways of this waterborne disease. [ABSTRACT FROM AUTHOR]

As cholera spread from Haiti to the Dominican Republic, Haitian migrants, a largely undocumented and stigmatized population in Dominican society, became a focus of public health concern. Concurrent to the epidemic, the Dominican legislature enacted new documentation requirements. This paper presents findings from an ethnographic study of anti-Haitian stigma in the Dominican Republic from June to August 2012. Eight focus group discussions (FGDs) were held with Haitian and Dominican community members. Five in-depth interviews were held with key informants in the migration policy sector. Theoretical frameworks of stigma's moral experience guided the analysis of how cholera was perceived, ways in which blame was assigned and felt and the relationship between documentation and healthcare access. In FGDs, both Haitians and Dominicans expressed fear of cholera and underscored the importance of public health messages to prevent the epidemic's spread. However, health messages also figured into experiences of stigma and rationales for blame. For Dominicans, failure to follow public health advice justified the blame of Haitians and seemed to confirm anti-Haitian sentiments. Haitians communicated a sense of powerlessness to follow public health messages given structural constraints like lack of safe water and sanitation, difficulty accessing healthcare and lack of documentation. In effect, by making documentation more difficult to obtain, the migration policy undermined cholera programs and contributed to ongoing processes of moral disqualification. Efforts to eliminate cholera from the island should consider how policy and stigma can undermine public health campaigns and further jeopardize the everyday 'being-in-the-world' of vulnerable groups.

Cholera is a common infectious disease caused by Vibrio cholerae, which has different infectivity. In this paper, we propose a cholera model with hyperinfectious and hypoinfectious vibrios, in which both human-to-human and environment-to-human transmissions are considered. By analyzing the characteristic equations, the local stability of disease-free and endemic equilibria is established. By using Lyapunov functionals and LaSalle's invariance principle, it is verified that the global threshold dynamics of the model can be completely determined by the basic reproduction number. Numerical simulations are carried out to illustrate the corresponding theoretical results and describe the cholera outbreak in Haiti. The study of optimal control helps us seek cost-effective solutions of time-dependent control strategies against cholera outbreaks, which shows that control strategies, such as vaccination and sanitation, should be taken at the very beginning of the outbreak and become less necessary after a certain period.

Background: In October 2010, Haiti was struck by a large-scale cholera epidemic. The Haitian government, UNICEF and other international partners launched an unprecedented nationwide alert-response strategy in July 2013. Coordinated NGOs recruited local rapid response mobile teams to conduct case-area targeted interventions (CATIs), including education sessions, household decontamination by chlorine spraying, and distribution of chlorine tablets. An innovative red-orange-green alert system was also established to monitor the epidemic at the communal scale on a weekly basis. Our study aimed to describe and evaluate the exhaustiveness, intensity and quality of the CATIs in response to cholera alerts in Haiti between July 2013 and June 2017., Methodology/principal Findings: We analyzed the response to 7,856 weekly cholera alerts using routine surveillance data and severity criteria, which was based on the details of 31,306 notified CATIs. The odds of CATI response during the same week (exhaustiveness) and the number of complete CATIs in responded alerts (intensity and quality) were estimated using multivariate generalized linear mixed models and several covariates. CATIs were carried out significantly more often in response to red alerts (adjusted odds ratio (aOR) [95%-confidence interval, 95%-CI], 2.52 [2.22-2.87]) compared with orange alerts. Significantly more complete CATIs were carried out in response to red alerts compared with orange alerts (adjusted incidence ratio (aIR), 1.85 [1.73-1.99]). Over the course of the eight-semester study, we observed a significant improvement in the exhaustiveness (aOR, 1.43 [1.38-1.48] per semester) as well as the intensity and quality (aIR, 1.23 [1.2-1.25] per semester) of CATI responses, independently of funds available for the strategy. The odds of launching a CATI response significantly decreased with increased rainfall (aOR, 0.99 [0.97-1] per each accumulated cm). Response interventions were significantly heterogeneous between NGOs, communes and departments., Conclusions/significance: The implementation of a nationwide case-area targeted rapid response strategy to control cholera in Haiti was feasible albeit with certain obstacles. Such feedback from the field and ongoing impact studies will be very informative for actors and international donors involved in cholera control and elimination in Haiti and in other affected countries., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: For authors working for the United Nations Children's Fund, Haiti (GB, CE, SB and EB): UNICEF-Haiti helped the Haitian Ministry of Health and Population (MSPP) to implement the alert-response strategy to control cholera in Haiti. UNICEF-Haiti received funds from several governments and institutions such as ECHO, DFID and CERF. These institutions had no involvement in study design, collection analysis and interpretation of data, writing of the report, and decision to submit the paper for publication. For authors working for Assistance Publique – Hôpitaux de Marseille (SR, JG, LO and RP): APHM, a French university-hospital, was mandated by the Haitian Ministry of Health and UNICEF-Haiti and granted by UNICEF-Haiti to provide the alert-response strategy to control cholera with prospective epidemiological analysis and evaluation. This study aimed to present and assess this strategy. Some UNICEF-Haiti staff played a role in study design, data collection and analysis, decision to publish, and preparation of the manuscript. For authors working for Ministry of Public Health and Population (EM, RB, KP, JB, PA and FDG): To implement the alert-response strategy to control cholera in Haiti, MSPP received material and financial support from UNICEF-Haiti. This study aimed to present and assess this strategy. Some UNICEF-Haiti staff played a role in study design, data collection and analysis, decision to publish, and preparation of the manuscript. For authors who were temporally contracted by UNICEF-Haiti (AAA, LO and RB): In accordance with their respective institutions, these four authors were contracted during a few months by UNICEF-Haiti as external consultants to perform prospective epidemiological analysis and evaluation of the alert-response strategy to control cholera. Some UNICEF-Haiti staff played a role in study design, data collection and analysis, decision to publish, and preparation of the manuscript. These authors have with no competing interest: PG, SM

Diffusion of cholera and other diarrheal diseases in an informal settlement is a product of multiple behavioral, environmental and spatial risk factors. One of the most important components is the spatial interconnections among water points, drainage ditches, toilets and the intervening environment. This risk is also longitudinal and variable as water points fluctuate in relation to bacterial contamination. In this paper we consider part of this micro space complexity for three informal settlements in Port au Prince, Haiti. We expand on more typical epidemiological analysis of fecal coliforms at water points, drainage ditches and ocean sites by considering the importance of single point location fluctuation coupled with recording micro-space environmental conditions around each sample site. Results show that spatial variation in enteric disease risk occurs within neighborhoods, and that while certain trends are evident, the degree of individual site fluctuation should question the utility of both cross-sectional and more aggregate analysis. Various factors increase the counts of fecal coliform present, including the type of water point, how water was stored at that water point, and the proximity of the water point to local drainage. Some locations fluctuated considerably between being safe and unsafe on a monthly basis. Next steps to form a more comprehensive contextualized understanding of enteric disease risk in these environments should include the addition of behavioral factors and local insight.

Background: Fine-scale and longitudinal geospatial analysis of health risks in challenging urban areas is often limited by the lack of other spatial layers even if case data are available. Underlying population counts, residential context, and associated causative factors such as standing water or trash locations are often missing unless collected through logistically difficult, and often expensive, surveys. The lack of spatial context also hinders the interpretation of results and designing intervention strategies structured around analytical insights. This paper offers a ubiquitous spatial data collection approach using a spatial video that can be used to improve analysis and involve participatory collaborations. A case study will be used to illustrate this approach with three health risks mapped at the street scale for a coastal community in Haiti. Methods: Spatial video was used to collect street and building scale information, including standing water, trash accumulation, presence of dogs, cohort specific population characteristics, and other cultural phenomena. These data were digitized into Google Earth and then coded and analyzed in a GIS using kernel density and spatial filtering approaches. The concentrations of these risks around area schools which are sometimes sources of diarrheal disease infection because of the high concentration of children and variable sanitary practices will show the utility of the method. In addition schools offer potential locations for cholera education interventions. Results: Previously unavailable fine scale health risk data vary in concentration across the town, with some schools being proximate to greater concentrations of the mapped risks. The spatial video is also used to validate coded data and location specific risks within these "hotspots". Conclusions: Spatial video is a tool that can be used in any environment to improve local area health analysis and intervention. The process is rapid and can be repeated in study sites through time to track spatio-temporal dynamics of the communities. Its simplicity should also be used to encourage local participatory collaborations. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear deterministic model is proposed with a saturated treatment function. The expression of the basic reproduction number for the proposed model was obtained. The global dynamics of the proposed model was studied using the basic reproduction number and theory of dynamical systems. It is observed that proposed model exhibits backward bifurcation as multiple endemic equilibrium points exist when . The existence of backward bifurcation implies that making is not enough for disease eradication. This, in turn, makes it difficult to control the spread of cholera in the community. We also obtain a unique endemic equilibria when . The global stability of unique endemic equilibria is performed using the geometric approach. An extensive numerical study is performed to support our analytical results. Finally, we investigate two major cholera outbreaks, Zimbabwe (2008-09) and Haiti (2010), with the help of the present study. [ABSTRACT FROM AUTHOR]

Public health decisions must be made about when and how to implement interventions to control an infectious disease epidemic. These decisions should be informed by data on the epidemic as well as current understanding about the transmission dynamics. Such decisions can be posed as statistical questions about scientifically motivated dynamic models. Thus, we encounter the methodological task of building credible, data-informed decisions based on stochastic, partially observed, nonlinear dynamic models. This necessitates addressing the tradeoff between biological fidelity and model simplicity, and the reality of misspecification for models at all levels of complexity. We assess current methodological approaches to these issues via a case study of the 2010-2019 cholera epidemic in Haiti. We consider three dynamic models developed by expert teams to advise on vaccination policies. We evaluate previous methods used for fitting these models, and we demonstrate modified data analysis strategies leading to improved statistical fit. Specifically, we present approaches for diagnosing model misspecification and the consequent development of improved models. Additionally, we demonstrate the utility of recent advances in likelihood maximization for high-dimensional nonlinear dynamic models, enabling likelihood-based inference for spatiotemporal incidence data using this class of models. Our workflow is reproducible and extendable, facilitating future investigations of this disease system. Author summary: Quantitative understanding of infectious disease transmission dynamics relies upon mathematical models informed by scientific knowledge and relevant data. The models aim to provide a statistical description of the trajectory of an epidemic and its uncertainty, together with a representation of the underlying biological mechanisms. Evaluation of success at these goals is necessary in order for a model to provide a reliable tool for guiding evidence-based public policy interventions. In this article, we conduct a re-analysis of the 2010–2019 cholera outbreak in Haiti. We use this case study to investigate current procedures for fitting mechanistic models to time series data, while identifying limitations of these methodologies and proposing remedies. Our analysis presents methodology for diagnosing how well a model describes observed data. Using objective measures to assess model fit ensures that our evaluation is based on quantifiable criteria. Incorporating reproducibility into this assessment results in a framework that enables the validation or refinement of model based inferences when revisiting the data, facilitating scientific discovery. Our data analysis workflow is supported by recent advances in algorithms, software and hardware, which facilitate statistical fitting of nonlinear stochastic dynamic models to observed incidence data. However, inference for high-dimensional systems remains a methodological challenge. One of the models under consideration involves spatially coupled stochastic meta-populations, and we demonstrate how a recently developed algorithm permits likelihood-based inference and model diagnostics in this setting. We contend that raising the currently accepted standards of infectious disease modeling will result in a greater ability of scientists and policy makers to understand and respond to future infectious disease outbreaks. [ABSTRACT FROM AUTHOR]

Haiti has been in the midst of a cholera epidemic since October 2010. Rainfall is thought to be associated with cholera here, but this relationship has only begun to be quantitatively examined. In this paper, we quantitatively examine the link between rainfall and cholera in Haiti for several different settings (including urban, rural, and displaced person camps) and spatial scales, using a combination of statistical and dynamic models. Statistical analysis of the lagged relationship between rainfall and cholera incidence was conducted using case crossover analysis and distributed lag nonlinear models. Dynamic models consisted of compartmental differential equation models including direct (fast) and indirect (delayed) disease transmission, where indirect transmission was forced by empirical rainfall data. Data sources include cholera case and hospitalization time series from the Haitian Ministry of Public Health, the United Nations Water, Sanitation and Health Cluster, International Organization for Migration, and Hôpital Albert Schweitzer. Rainfall data was obtained from rain gauges from the U.S. Geological Survey and Haiti Regeneration Initiative, and remote sensing rainfall data from the National Aeronautics and Space Administration Tropical Rainfall Measuring Mission. A strong relationship between rainfall and cholera was found for all spatial scales and locations examined. Increased rainfall was significantly correlated with increased cholera incidence 4-7 days later. Forcing the dynamic models with rainfall data resulted in good fits to the cholera case data, and rainfall-based predictions from the dynamic models closely matched observed cholera cases. These models provide a tool for planning and managing the epidemic as it continues., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A cholera epidemic has claimed the lives of more than 8,000 Haitians and sickened 650,000 since the outbreak began in October 2010. Early intervention in the epidemic focused on case-finding, treatment, and water and sanitation interventions for prevention of transmission. Use of oral cholera vaccine (OCV) as part of a complementary set of control activities was considered but initially rejected by policymakers. In December 2011, the Minister of Health of Haiti called for a demonstration of the acceptability and feasibility of the use of OCV in urban and rural Haiti. This paper describes the collaborative activity that offered OCV to one region of the Artibonite Department of rural Haiti in addition to other ongoing treatment and control measures. Despite logistics and cold chain challenges, 45,417 persons were successfully vaccinated with OCV in the region, and 90.8% of these persons completed their second dose.

Successful and sustained efforts have been made to curtail the major cholera epidemic that occurred in Haiti in 2010 with the promotion of hygiene and sanitation measures, training of health personnel and establishment of treatment centers nationwide. Oral cholera vaccine (OCV) was introduced by the Haitian Ministry of Health as a pilot project in urban and rural areas. This paper reports the successful OCV pilot project led by GHESKIO Centers in the urban slums of Port-au-Prince where 52,357 persons received dose 1 and 90.8% received dose 2; estimated coverage of the at-risk community was 75%. This pilot study demonstrated the effort, community mobilization, and organizational capacity necessary to achieve these results in a challenging setting. The OCV intervention paved the way for the recent launching of a national cholera vaccination program integrated in a long-term ambitious and comprehensive plan to address Haiti's critical need in water security and sanitation.

The devastating Haitian cholera outbreak that began in October 2010 is the first known cholera epidemic in this island nation. Epidemiological and genomic data have provided strong evidence that United Nations security forces from Nepal introduced toxigenic Vibrio cholerae O1, the cause of epidemic cholera, to Haiti shortly before the outbreak arose. However, some have contended that indigenous V. cholerae contributed to the outbreak. In a recent paper (mBio 4:e00398-13, 2013), L. S. Katz et al. explored the nature and rate of changes in this ancient pathogen's genome during an outbreak, based on whole-genome sequencing of 23 Haitian V. cholerae clinical isolates obtained over a 20-month period. Notably, they detected point mutations, deletions, and inversions but found no insertion of horizontally transmitted DNA, arguing strongly against the idea that autochthonous V. cholerae donated DNA to the outbreak strain. Furthermore, they found that Haitian epidemic V. cholerae isolates were virtually untransformable. Comparative genomic analyses revealed that the Haitian isolates were nearly identical to isolates from Nepal and that the Nepalese-Haitian isolates were distinguishable from isolates circulating elsewhere in the world. Reconstruction of the phylogeny of the Haitian isolates was consistent with a single introduction of V. cholerae to Haiti sometime between late July and late October 2010, dates remarkably concordant with epidemiological observations. In aggregate, this paper provides additional compelling evidence that the V. cholerae strain responsible for the Haitian cholera epidemic came from Nepal and illustrates the power of whole-genome-based analyses for epidemiology, pathogen evolution, and forensics.

Great progress has been made in mathematical models of cholera transmission dynamics in recent years. However, little impact, if any, has been made by models upon public health decision-making and day-to-day routine of epidemiologists. This paper provides a brief introduction to the basics of ordinary differential equation models of cholera transmission dynamics. We discuss a basic model adapted from Codeço (2001), and how it can be modified to incorporate different hypotheses, including the importance of asymptomatic or inapparent infections, and hyperinfectious V. cholerae and human-to-human transmission. We highlight three important challenges of cholera models: (1) model misspecification and parameter uncertainty, (2) modeling the impact of water, sanitation and hygiene interventions and (3) model structure. We use published models, especially those related to the 2010 Haitian outbreak as examples. We emphasize that the choice of models should be dictated by the research questions in mind. More collaboration is needed between policy-makers, epidemiologists and modelers in public health. [ABSTRACT FROM AUTHOR]

In Haiti in 2017, the prevalence of serum vibriocidal antibody titers against Vibrio cholerae serogroup O1 among adults was 12.4% in Cerca-la-Source and 9.54% in Mirebalais, suggesting a high recent prevalence of infection. Improved surveillance programs to monitor cholera and guide public health interventions in Haiti are necessary. [ABSTRACT FROM AUTHOR]

Responding to infrastructural damage in the aftermath of natural disasters at a national, regional, and local level poses a significant challenge. Damage to road networks, clean water supply, and sanitation infrastructures, as well as social amenities like schools and hospitals, exacerbates the circumstances. As safe water sources are destroyed or mixed with contaminated water during a disaster, the risk of a waterborne disease outbreak is elevated in those disaster-affected locations. A country such as Haiti, where a large quantity of the population is deprived of safe water and basic sanitation facilities, would suffer more in post-disaster scenarios. Early warning of waterborne diseases like cholera would be of great help for humanitarian aid, and the management of disease outbreak perspectives. The challenging task in disease forecasting is to identify the suitable variables that would better predict a potential outbreak. In this study, we developed five (5) models including a machine learning approach, to identify and determine the impact of the environmental and social variables that play a significant role in post-disaster cholera outbreaks. We implemented the model setup with cholera outbreak data in Haiti after the landfall of Hurricane Matthew in October 2016. Our results demonstrate that adding high-resolution data in combination with appropriate social and environmental variables is helpful for better cholera forecasting in a post-disaster scenario. In addition, using a machine learning approach in combination with existing statistical or mechanistic models provides important insights into the selection of variables and identification of cholera risk hotspots, which can address the shortcomings of existing approaches. [ABSTRACT FROM AUTHOR]

We improve a recent mathematical model for cholera by adding a time delay that represents the time between the instant at which an individual becomes infected and the instant at which he begins to have symptoms of cholera disease. We prove that the delayed cholera model is biologically meaningful and analyze the local asymptotic stability of the equilibrium points for positive time delays. An optimal control problem is proposed and analyzed, where the goal is to obtain optimal treatment strategies, through quarantine, that minimize the number of infective individuals and the bacterial concentration, as well as treatment costs. Necessary optimality conditions are applied to the delayed optimal control problem, with a L1 type cost functional. We show that the delayed cholera model fits better the cholera outbreak that occurred in the Department of Artibonite - Haiti, from 1 November 2010 to 1 May 2011, than the non-delayed model. Considering the data of the cholera outbreak in Haiti, we solve numerically the delayed optimal control problem and propose solutions for the outbreak control and eradication. [ABSTRACT FROM AUTHOR]

After belatedly apologizing for the cholera epidemic in Haiti, the 'New Approach to Cholera in Haiti' by the UN and the promise of material assistance to victims through a 'victim-centred approach' highlight how the victims turn and the socio-economic turn are increasingly pivotal in the field of transitional justice. In light of these growing calls, we suggest a matrix to clarify the debate made of two separate dimensions: the focus of reparations – collective versus individual – and the means of reparations – symbolic versus material. Based on fieldwork conducted in March 2017 in the communities most affected by the cholera outbreak, this article demonstrates how the tensions between reparations offered by the UN (with a preference for collective symbolic reparations) and the reparations demanded by the victims (individual material reparations) can help understand the current stalemate in Haiti, and hopefully inform the next steps in the process of remedy for the victims. [ABSTRACT FROM AUTHOR]

UN Peacekeepers stationed on the banks of Haiti's largest river, the Artibonite, unleashed a cholera epidemic upon the country ten years ago, but the almost one million people affected still have not seen justice. This, despite the mobilization of grassroots organizations, human rights professionals, students, journalists and independent experts in international human rights law. This article aims to articulate rights violations in the Haiti cholera case, discuss the lack of accountability, and analyse efforts by advocates to overcome obstacles to justice through a multi-faceted intervention involving the UN Special Procedures system. Human rights-based approaches to UN accountability coupled with analyses of the UN's organizational immunity foreground the continued lack of remedy for the victims of cholera, which is a violation of their human rights attributable to the UN. In conducting public advocacy and investigating the issue of UN responsibility for cholera in Haiti, UN Special Rapporteurs like Philip Alston also relied on a human-rights based approach that built some public pressure for accountability. While advocates continue to push for accountability after a 10-year epidemic, and accountability is possible, the as-yet unsatisfactory resolution to the Haiti cholera case points to a need for UN reform to create more local, democratic structures of governance that are responsive to human rights obligations, in the face of considerable political, economic and social forces in Haiti and internationally that weigh against accountability. [ABSTRACT FROM AUTHOR]

Household spraying is a commonly implemented, yet an under-researched, cholera response intervention where a response team sprays surfaces in cholera patients' houses with chlorine. We conducted mixed-methods evaluations of three household spraying programs in the Democratic Republic of Congo and Haiti, including 18 key informant interviews, 14 household surveys and observations, and 418 surface samples collected before spraying, 30 minutes and 24 hours after spraying. The surfaces consistently most contaminated with Vibrio cholerae were food preparation areas, near the patient's bed and the latrine. Effectiveness varied between programs, with statistically significant reductions in V. cholerae concentrations 30 minutes after spraying in two programs. Surface contamination after 24 hours was variable between households and programs. Program challenges included difficulty locating households, transportation and funding limitations, and reaching households quickly after case presentation (disinfection occurred 2–6 days after reported cholera onset). Program advantages included the concurrent deployment of hygiene promotion activities. Further research is indicated on perception, recontamination, cost-effectiveness, viable but nonculturable V. cholerae, and epidemiological coverage. We recommend that, if spraying is implemented, spraying agents should: disinfect surfaces systematically until wet using 0.2/2.0% chlorine solution, including kitchen spaces, patients' beds, and latrines; arrive at households quickly; and, concurrently deploy hygiene promotion activities. Author summary: Cholera remains a global health concern, with an estimated 2.9 million cases and 95,000 deaths per year. Household spraying is an outbreak response activity where the houses of cholera patients are disinfected by spraying chlorine to interrupt cholera transmission within households. The effectiveness and appropriateness of this intervention have been questioned but it remains widely implemented. We conducted three mixed-methods evaluations of household spraying programs in the Democratic Republic of the Congo and in Haiti. By sampling surfaces before, 30 minutes and 24 hours after spraying, we were able to identify household surfaces that were consistently the most contaminated at baseline (namely food preparation areas, patients' beds, and latrines). We also found that spraying chlorine could inactivate bacteria on household surfaces but that effectiveness was inconsistent, likely due to differences in spraying protocols between programs such as the amount of chlorine applied onto surfaces. Through key informant interviews, structured observations and household surveys, we also gained insights into the advantages and challenges of each program. This work contributes to the scientific evidence base necessary to optimize cholera response strategies; the combination of microbiological and qualitative information allowed us to formulate concrete recommendations for outbreak response programs. [ABSTRACT FROM AUTHOR]

Cholera continues to be an important public health concern in developing countries where proper hygiene and sanitation are compromised. This severe diarrheal disease is caused by the Gram-negative pathogen Vibrio cholerae belonging to serogroups O1 and O139. Cholera toxin (CT) is the prime virulence factor and is directly responsible for the disease manifestation. The ctxB gene encodes cholera toxin B subunit (CTB) whereas the A subunit (CTA) is the product of ctxA gene. Enzymatic action of CT depends on binding of B pentamers to the lipid-based receptor ganglioside GM1. In recent years, emergence of V. cholerae Haitian variant strains with ctxB7 allele and their rapid spread throughout the globe has been linked to various cholera outbreaks in Africa and Asia. These strains produce classical type (WT) CTB except for an additional mutation in the signal sequence region where an asparagine (N) residue replaces a histidine (H) at the 20th amino acid position (H20N) of CTB precursor (pre-CTB). Here we report that Haitian variant V. cholerae O1 strains isolated in Kolkata produced higher amount of CT compared to contemporary O1 El Tor variant strains under in vitro virulence inducing conditions. We observed that the ctxB7 allele, itself plays a pivotal role in higher CT production. Based on our in silico analysis, we hypothesized that higher accumulation of toxin subunits from ctxB7 allele might be attributed to the structural alteration at the CTB signal peptide region of pre-H20N CTB. Overall, this study provides plausible explanation regarding the hypertoxigenic phenotype of the Haitian variant strains which have spread globally, possibly through positive selection for increased pathogenic traits. Author summary: Cholera remains to be a major public health burden in the developing countries. Toxigenic strains of the Gram-negative organism Vibrio cholerae belonging to serogroups O1 and O139 are the etiological agents for this dreadful disease. These strains secrete CT into the extracellular milieu which upon ingestion of contaminated food or water, results in severe loss of water and electrolytes. In the recent past, V. cholerae O1 strains with the signature ctxB7 allele have propagated through many of the cholera endemic regions in Africa and Asia. These strains were also identified as the cause for the devastating cholera epidemic in Haiti that killed around 8000 victims. It was demonstrated that the Haitian isolate had been associated with hypertoxigenic phenotype and increased virulence. However, whether the ctxB7 allele may have any role to play in increased CT production phenotype of the Haitian variants remains obscure. We observed that the ctxB7 allele plays a pivotal role in heightened CT production, although any link between increased CT production and hypervirulence phenotypes remains undefined. [ABSTRACT FROM AUTHOR]

Non-profit organizations play a central role in responding to the devastating consequences of epidemic outbreaks in developing economies. We propose an epidemic response model in resource-limited countries that determines the number, size, and location of treatment facilities, deploys critical medical staff, locates ambulances to triage points, and organizes the transportation of severely ill patients to treatment facilities. The model is based on the 2010 cholera outbreak in Haiti and is general enough to be used for similar epidemic outbreaks. The model enables not-for-profit decision-makers to assess health care triage capabilities, transportation needs, and requirements for medical personnel staffing and deployment. We propose an algorithmic procedure using hierarchical constraints and valid inequalities that reduce the solution time by one order of magnitude. Additionally, we propose a framework that can be used to optimally allocate a donation, to determine a list of priorities for earmarked donations, and to perform a cost-benefit analysis of an intervention strategy financed by a donation. The model is formulated as a large integer problem with many symmetries. An extended analysis based on the 2010 cholera outbreak in Haiti provides insights about: the criticality of the resources, the implementation of a balanced response strategy, the optimal allocation of resources in terms of the severity of the attack rate, and the benefits of the proposed response approach with respect to other intervention strategies. [ABSTRACT FROM AUTHOR]

Oral cholera vaccines (OCVs) are being increasingly employed, but current killed formulations generally require multiple doses and lack efficacy in young children. We recently developed a new live-attenuated OCV candidate (HaitiV) derived from a Vibrio cholerae strain isolated during the 2010 Haiti cholera epidemic. HaitiV exhibited an unexpected probiotic-like activity in infant rabbits, preventing intestinal colonization and disease by wild-type V. cholerae before the onset of adaptive immunity. However, it remained unknown whether HaitiV would behave similarly to other OCVs to stimulate adaptive immunity against V. cholerae. Here, we orally immunized adult germ-free female mice to test HaitiV’s immunogenicity. HaitiV safely and stably colonized vaccinated mice and induced known adaptive immune correlates of cholera protection within 14 days of administration. Pups born to immunized mice were protected against lethal challenges of both homologous and heterologous V. cholerae strains. Cross-fostering experiments revealed that protection was not dependent on vaccine colonization in or transmission to the pups. These findings demonstrate the protective immunogenicity of HaitiV and support its development as a new tool for limiting cholera. [ABSTRACT FROM AUTHOR]

The United Nations ("U.N.") has been looked at globally and historically as an international organization that has given aid to millions of people in the hopes of promoting peace and reducing human rights violations. It is no surprise then that many countries have welcomed U.N. troops with open arms in the hopes of stabilizing communities. However, instead of receiving aid, imagine receiving a deadly disease. Imagine having the nearby river that has been your only source of water for drinking, laundry, and bathing for decades turned into a waste dump. It is from that river turned waste dump that you-and hundreds of thousands of other innocent people-have now contracted cholera. This was the reality for thousands of Haitian citizens who now continue to suffer from cholera due to a U.N. base's negligent disposal of its troops' waste into a river the Haitian citizens depended on for survival. Despite being responsible for the cholera epidemic now plaguing Haiti-a third world country with too few resources struggling to support its citizens-the U.N. has failed to not only properly respond to the outbreak, but also to accept legal responsibility This Note discusses different options to bring about financial, legal, and actual relief to the victims of the cholera outbreak in Haiti. It reviews the failed attempts of Haitian victims to hold the U.N. legally accountable for its actions and seeks to answer the following question: in what ways can relief be achieved, if at all, in the human rights realm. [ABSTRACT FROM AUTHOR]

More than three years after its appearance in Haiti, cholera has already caused more than 8,500 deaths and 695,000 infections and it is feared to become endemic. However, no clear evidence of a stable environmental reservoir of pathogenic Vibrio cholerae, the infective agent of the disease, has emerged so far, suggesting the possibility that the transmission cycle of the disease is being maintained by bacteria freshly shed by infected individuals. Should this be the case, cholera could in principle be eradicated from Haiti. Here, we develop a framework for the estimation of the probability of extinction of the epidemic based on current information on epidemiological dynamics and health-care practice. Cholera spreading is modeled by an individual-based spatially-explicit stochastic model that accounts for the dynamics of susceptible, infected and recovered individuals hosted in different local communities connected through hydrologic and human mobility networks. Our results indicate that the probability that the epidemic goes extinct before the end of 2016 is of the order of 1 %. This low probability of extinction highlights the need for more targeted and effective interventions to possibly stop cholera in Haiti. [ABSTRACT FROM AUTHOR]

We investigated the antimicrobial susceptibility of 50 environmental isolates of Vibrio cholerae non-O1/non-O139 collected in surface waters in Haiti in July 2012, during an active cholera outbreak. A panel of 16 antibiotics was tested on the isolates using the disk diffusion method and PCR detection of seven resistance-associated genes (strA/B, sul1/2, ermA/B, and mefA). All isolates were susceptible to amoxicillin-clavulanic acid, cefotaxime, imipenem, ciprofloxacin, norfloxacin, amikacin, and gentamicin. Nearly a quarter (22.0%) of the isolates were susceptible to all 16 antimicrobials tested and only 8.0% of the isolates (n = 4) were multidrug-resistant. The highest proportions of resistant isolates were observed for sulfonamide (70.0%), amoxicillin (12.0%), and trimethoprim-sulfamethoxazole (10.0%). One strain was resistant to erythromycin and one to doxycycline, two antibiotics used to treat cholera in Haiti. Among the 50 isolates, 78% possessed at least two resistance-associated genes, and the genes sul1, ermA, and strB were detected in all four multidrug-resistant isolates. Our results clearly indicate that the autochthonous population of V. cholerae non-O1/non-O139 found in surface waters in Haiti shows antimicrobial patterns different from that of the outbreak strain. The presence in the Haitian aquatic environment of V. cholerae non-O1/non-O139 with reduced susceptibility or resistance to antibiotics used in human medicine may constitute a mild public health threat. [ABSTRACT FROM AUTHOR]

The legalization of world politics is often celebrated for reducing impunity for those who contribute to humanitarian crises. This may sometimes be true but the opposite is also true. In 2010, United Nations peacekeepers unwittingly brought cholera to Haiti and sparked an epidemic. Nearly a million people were made sick and 8,500 died. Legal activists have sought to hold the UN responsible for the harms it caused and win compensation for the cholera victims. However, these efforts have been stymied by the structures of public international law--particularly UN immunity--which effectively insulate the organization from accountability. In short, the UN is empowered, and the cholera victims disempowered, by legalization. The Haiti case powerfully illustrates the dangers of legalism, which have been largely overlooked in discussions of international law, and suggests that law alone is an inadequate arbiter of responsibility in international politics. [ABSTRACT FROM AUTHOR]

In the current study, a comprehensive, data driven, mathematical model for cholera transmission in Haiti is presented. Along with the inclusion of short cycle human-to-human transmission and long cycle human-to-environment and environment-to-human transmission, this novel dynamic model incorporates both the reported cholera incidence and remote sensing data from the Ouest Department of Haiti between 2010 to 2014. The model has separate compartments for infectious individuals that include different levels of infectivity to reflect the distribution of symptomatic and asymptomatic cases in the population. The environmental compartment, which serves as a source of exposure to toxigenic V. cholerae, is also modeled separately based on the biology of causative bacterium, the shedding of V. cholerae O1 by humans into the environment, as well as the effects of precipitation and water temperature on the concentration and survival of V. cholerae in aquatic reservoirs. Although the number of reported cholera cases has declined compared to the initial outbreak in 2010, the increase in the number of susceptible population members and the presence of toxigenic V. cholerae in the environment estimated by the model indicate that without further improvements to drinking water and sanitation infrastructures, intermittent cholera outbreaks are likely to continue in Haiti. [ABSTRACT FROM AUTHOR]

The operation of a health care facility, such as a cholera or Ebola treatment center in an emergency setting, results in the production of pathogen-laden wastewaters that may potentially lead to onward transmission of the disease. The research presented here evaluated the design and operation of a novel treatment system, successfully used by Médecins Sans Frontières in Haiti to disinfect CTC wastewaters in situ, eliminating the need for road haulage and disposal of the waste to a poorly-managed hazardous waste facility, thereby providing an effective barrier to disease transmission through a novel but simple sanitary intervention. The physico-chemical protocols eventually successfully treated over 600 m3 of wastewater, achieving coagulation/flocculation and disinfection by exposure to high pH (Protocol A) and low pH (Protocol B) environments, using thermotolerant coliforms as a disinfection efficacy index. In Protocol A, the addition of hydrated lime resulted in wastewater disinfection and coagulation/flocculation of suspended solids. In Protocol B, disinfection was achieved by the addition of hydrochloric acid, followed by pH neutralization and coagulation/flocculation of suspended solids using aluminum sulfate. Removal rates achieved were: COD >99%; suspended solids >90%; turbidity >90% and thermotolerant coliforms >99.9%. The proposed approach is the first known successful attempt to disinfect wastewater in a disease outbreak setting without resorting to the alternative, untested, approach of 'super chlorination' which, it has been suggested, may not consistently achieve adequate disinfection. A basic analysis of costs demonstrated a significant saving in reagent costs compared with the less reliable approach of super-chlorination. The proposed approach to in situ sanitation in cholera treatment centers and other disease outbreak settings represents a timely response to a UN call for onsite disinfection of wastewaters generated in such emergencies, and the 'Coalition for Cholera Prevention and Control' recently highlighted the research as meriting serious consideration and further study. Further applications of the method to other emergency settings are being actively explored by the authors through discussion with the World Health Organization with regards to the ongoing Ebola outbreak in West Africa, and with the UK-based NGO Oxfam with regards to excreta-borne disease management in the Philippines and Myanmar, as a component of post-disaster incremental improvements to local sanitation chains. Author Summary: When an outbreak of infectious disease occurs in a low-resource setting, the rapid construction of emergency healthcare facilities may significantly reduce mortality. The facilities also result in the generation of large volumes of highly contaminated fecal waste that represents a potential basis for further disease transmission. Infection protection and control strategies at healthcare facilities must therefore include measures to establish and maintain good water supplies, sanitation and hygiene (WASH). Even where the pathogen of concern is not waterborne, health-care providers have a 'duty-of-care' to protect workers and neighboring communities from all excreta-borne diseases. In this study, the authors successfully demonstrated, for the first time, the in situ disinfection of wastewaters from cholera treatment centers during the Haiti cholera outbreak, using a low-cost physicochemical method. The approach is currently being adapted by NGOs to help manage human excreta in other emergency settings, including the current Ebola outbreak. Although the Ebola virus is relatively fragile, it may exist in high concentrations in the bodily fluids (including feces) of those with the disease. The approach to in situ disinfection of excreta described here may therefore support infection control in outbreaks of Ebola and other infectious diseases. [ABSTRACT FROM AUTHOR]

Background: In 2010 and 2011, Haiti was heavily affected by a large cholera outbreak that spread throughout the country. Although national health structure-based cholera surveillance was rapidly initiated, a substantial number of community cases might have been missed, particularly in remote areas. We conducted a community-based survey in a large rural, mountainous area across four districts of the Nord department including areas with good versus poor accessibility by road, and rapid versus delayed response to the outbreak to document the true cholera burden and assess geographic distribution and risk factors for cholera mortality. Methodology/Principal Findings: A two-stage, household-based cluster survey was conducted in 138 clusters of 23 households in four districts of the Nord Department from April 22nd to May 13th 2011. A total of 3,187 households and 16,900 individuals were included in the survey, of whom 2,034 (12.0%) reported at least one episode of watery diarrhea since the beginning of the outbreak. The two more remote districts, Borgne and Pilate were most affected with attack rates up to 16.2%, and case fatality rates up to 15.2% as compared to the two more accessible districts. Care seeking was also less frequent in the more remote areas with as low as 61.6% of reported patients seeking care. Living in remote areas was found as a risk factor for mortality together with older age, greater severity of illness and not seeking care. Conclusions/Significance: These results highlight important geographical disparities and demonstrate that the epidemic caused the highest burden both in terms of cases and deaths in the most remote areas, where up to 5% of the population may have died during the first months of the epidemic. Adapted strategies are needed to rapidly provide treatment as well as prevention measures in remote communities. Author Summary: In October 2010, a large cholera outbreak was declared in Haiti and rapidly spread throughout the country, quickly overwhelming the existing health system. Specialized treatment structures were opened rapidly, generally in cities or large villages, and decentralized treatment units or rehydration points were gradually opened later on. To gain insight into the true burden of the cholera outbreak in the community and on potential geographical differences due to accessibility, we conducted a survey in April–May 2011 in a large rural area across four mountainous districts in the Nord department. We interviewed 3,187 households, corresponding to 16,900 individuals, of whom 2,034 (12%) had had diarrhea, probably cholera, since the beginning of the outbreak. The two most remote districts showed higher proportions of population affected by the disease, up to 16.2%, and higher proportions of deaths among patients with probable cholera, up to 15.2%, than the two districts with better accessibility. Remote populations, older patients, severe cases and those not seeking care were at increased risk of dying of the disease. These results show the very high burden of the cholera outbreak in remote areas, emphasizing the need to develop strategies to rapidly provide treatment and prevention measures in remote communities. [ABSTRACT FROM AUTHOR]

In October, 2010, epidemic cholera was reported for the first time in Haiti in over 100 years. Establishment of cholera endemicity in Haiti will be dependent in large part on the continued presence of toxigenic V. cholerae O1 in aquatic reservoirs. The rugose phenotype of V. cholerae, characterized by exopolysaccharide production that confers resistance to environmental stress, is a potential contributor to environmental persistence. Using a microbiologic medium promoting high-frequency conversion of smooth to rugose (S–R) phenotype, 80 (46.5%) of 172 V. cholerae strains isolated from clinical and environmental sources in Haiti were able to convert to a rugose phenotype. Toxigenic V. cholerae O1 strains isolated at the beginning of the epidemic (2010) were significantly less likely to shift to a rugose phenotype than clinical strains isolated in 2012/2013, or environmental strains. Frequency of rugose conversion was influenced by incubation temperature and time. Appearance of the biofilm produced by a Haitian clinical rugose strain (altered biotype El Tor HC16R) differed from that of a typical El Tor rugose strain (N16961R) by confocal microscopy. On whole-genome SNP analysis, there was no phylogenetic clustering of strains showing an ability to shift to a rugose phenotype. Our data confirm the ability of Haitian clinical (and environmental) strains to shift to a protective rugose phenotype, and suggest that factors such as temperature influence the frequency of transition to this phenotype. [ABSTRACT FROM AUTHOR]

The article provides an overview of the National Program for the Elimination of Lymphatic Filariasis (NPELF) in Haiti. Despite facing political crises, natural disasters, and a cholera outbreak, the program has achieved full geographic coverage and reached over 8 million people in 2012. The program aims to treat lymphatic filariasis and intestinal helminth infections through preventive chemotherapy. It has expanded its coverage across all provinces in Haiti and provides care for patients with LF-related morbidity. The article acknowledges the challenges faced by the program and highlights the support and contributions of various organizations and individuals. [Extracted from the article]

Background: Haiti's cholera epidemic has been devastating partly due to underlying weak infrastructure and limited clean water and sanitation. A comprehensive approach to cholera control is crucial, yet some have argued that oral cholera vaccination (OCV) might result in reduced hygiene practice among recipients. We evaluated the impact of an OCV campaign on knowledge and health practice in rural Haiti. Methodology/Principal Findings: We administered baseline surveys on knowledge and practice relevant to cholera and waterborne disease to every 10th household during a census in rural Haiti in February 2012 (N = 811). An OCV campaign occurred from May–June 2012 after which we administered identical surveys to 518 households randomly chosen from the same region in September 2012. We compared responses pre- and post-OCV campaign. Post-vaccination, there was improved knowledge with significant increase in percentage of respondents with ≥3 correct responses on cholera transmission mechanisms (odds ratio[OR] 1.91; 95% confidence interval[CI] 1.52–2.40), preventive methods (OR 1.83; 95% CI 1.46–2.30), and water treatment modalities (OR 2.75; 95% CI 2.16–3.50). Relative to pre-vaccination, participants were more likely post-OCV to report always treating water (OR 1.62; 95% CI 1.28–2.05). Respondents were also more likely to report hand washing with soap and water >4 times daily post-vaccine (OR 1.30; 95% CI 1.03–1.64). Knowledge of treating water as a cholera prevention measure was associated with practice of always treating water (OR 1.47; 95% CI 1.14–1.89). Post-vaccination, knowledge was associated with frequent hand washing (OR 2.47; 95% CI 1.35–4.51). Conclusion: An OCV campaign in rural Haiti was associated with significant improvement in cholera knowledge and practices related to waterborne disease. OCV can be part of comprehensive cholera control and reinforce, not detract from, other control efforts in Haiti. Author Summary: In October 2010, Haiti experienced a cholera outbreak that is now considered one of the largest cholera epidemics in recent history. A comprehensive approach is necessary to successfully fight the epidemic and proven methods for controlling cholera include improving access to clean water and sanitation as well as widespread hygiene education. In addition, there are two safe cholera vaccines approved for use. The authors conducted surveys before and after a cholera vaccination campaign, that included a public health educational component, in rural Haiti; surveys addressed knowledge of cholera and hygiene practices such as hand washing and water treatment, which are crucial for preventing waterborne diseases such as cholera. The authors found that after the vaccination campaign, knowledge of cholera improved significantly. There was also significant increase in reported hand washing and water treatment post vaccination. Furthermore, there was an association between knowledge and hygiene practices. Therefore, this study demonstrates that cholera vaccination can be a complementary tool in the fight against cholera in Haiti and will not detract from other control efforts. [ABSTRACT FROM AUTHOR]

Background: The association between cholera in pregnancy and negative fetal outcome has been described since the 19th century. However, there is limited published literature on the subject. We describe pregnancy outcomes from a specialized multidisciplinary hospital unit at the onset of a large cholera outbreak in Haiti in 2010 and 2011. Methods: Pregnant women with cholera were hospitalized in a specialized unit within the MSF hospital compound in Léogâne and treated using standard cholera treatment guidelines but with earlier, more intense fluid replacement. All women had intravenous access established at admission regardless of their hydration status, and all received antibiotic treatment. Data were collected on patient demographics, pregnancy and cholera status, and pregnancy outcome. In this analysis we calculated risk ratios for fetal death and performed logistic regression analysis to control for confounding factors. Results: 263 pregnant women with cholera were hospitalized between December 2010 and July 2011. None died during hospitalization, 226 (86%) were discharged with a preserved pregnancy and 16 (6%) had live fullterm singleton births, of whom 2 died within the first 5 days postpartum. The remaining 21 pregnancies (8%) resulted in intrauterine fetal death. The risk of fetal death was associated with factors reflecting severity of the cholera episode: after adjusting for confounding factors, the strongest risk factor for fetal death was severe maternal dehydration (adjusted risk ratio for severe vs. mild dehydration was 9.4, 95% CI 2.5–35.3, p = 0.005), followed by severe vomiting (adjusted risk ratio 5.1, 95% 1.1–23.8, p = 0.041). Conclusion: This is the largest cohort of pregnant women with cholera described to date. The main risk factor identified for fetal death was severity of dehydration. Our experience suggests that establishing specialized multidisciplinary units which facilitate close follow-up of both pregnancy and dehydration status due to cholera could be beneficial for patients, especially in large epidemics. Author Summary: Cholera in pregnancy has been long associated with high rates of stillbirths and abortions, but there is very limited published literature describing this association or possible mechanisms. During the major cholera epidemic that hit Haiti in October 2010, we set-up a specialized cholera treatment unit for pregnant women inside the Médecins sans Frontières hospital in Léogâne, allowing for intensive follow-up of cholera-associated dehydration and of pregnancy, and facilitating access to high-quality obstetric and neonatal services in case of complications. To describe the pregnancy outcomes and risk factors for fetal death, we analyzed routinely collected data from patient files. Of 263 women hospitalized, 21 (8%) lost their pregnancy during hospitalization for cholera; an additional 16 (6%) delivered a live baby at the hospital, and the remaining 226 women (86%) were discharged with preserved pregnancy. The risk factor most strongly associated with fetal demise was severity of dehydration at admission. In large epidemics, multidisciplinary units can help prevent negative maternal, fetal and neonatal outcomes. [ABSTRACT FROM AUTHOR]

Background: In October 2010, cholera importation in Haiti triggered an epidemic that rapidly proved to be the world's largest epidemic of the seventh cholera pandemic. To establish effective control and elimination policies, strategies rely on the analysis of cholera dynamics. In this report, we describe the spatio-temporal dynamics of cholera and the associated environmental factors. Methodology/Principal findings: Cholera-associated morbidity and mortality data were prospectively collected at the commune level according to the World Health Organization standard definition. Attack and mortality rates were estimated and mapped to assess epidemic clusters and trends. The relationships between environmental factors were assessed at the commune level using multivariate analysis. The global attack and mortality rates were 488.9 cases/10,000 inhabitants and 6.24 deaths/10,000 inhabitants, respectively. Attack rates displayed a significantly high level of spatial heterogeneity (varying from 64.7 to 3070.9 per 10,000 inhabitants), thereby suggesting disparate outbreak processes. The epidemic course exhibited two principal outbreaks. The first outbreak (October 16, 2010–January 30, 2011) displayed a centrifugal spread of a damping wave that suddenly emerged from Mirebalais. The second outbreak began at the end of May 2011, concomitant with the onset of the rainy season, and displayed a highly fragmented epidemic pattern. Environmental factors (river and rice fields: p<0.003) played a role in disease dynamics exclusively during the early phases of the epidemic. Conclusion: Our findings demonstrate that the epidemic is still evolving, with a changing transmission pattern as time passes. Such an evolution could have hardly been anticipated, especially in a country struck by cholera for the first time. These results argue for the need for control measures involving intense efforts in rapid and exhaustive case tracking. Author Summary: Cholera is the prototypical "waterborne" disease that can provoke deadly acute watery diarrhea epidemics in settings deprived of clean water and proper sanitation. In spite chronic deprivation, Haiti had been spared cholera for a century until the vibrio was imported in October 2010, which triggered the largest national epidemic ever recorded. To better understand the progression of the epidemic and adapt control measures, we describe and analyze the spatio-temporal dynamics and underlying factors associated with the first year of this cholera epidemic in Haiti. Attack rates reached highly heterogeneous levels between communes (from 64.7 to 3070.9 cases per 10,000 inhabitants), thereby suggesting disparate outbreak processes. While the first principal outbreak spread centrifugally like a damping wave that suddenly emerged from Mirebalais and Lower Artibonite, a second principal outbreak erupted at the end of May 2011, concomitant with the rainy season, and displayed a highly fragmented epidemic pattern. Environmental factors, such as rivers and rice fields, appeared to play a role in disease dynamics exclusively during the beginning of the epidemic. The dynamics of the cholera epidemic varied from place to place as time passed, following no clearly predictable scheme. Therefore, cholera control measures in Haiti should include rapid and exhaustive case tracking. [ABSTRACT FROM AUTHOR]

For a century and a half cholera has been a stigmatizing disease. That the entire world was susceptible to it seemed merely to accentuate its association with Asia, and particularly with Bengal and its people. The recent epidemic in Haiti suggests that cholera still carries stigma. That stigma is the product of epistemic practices within an interdisciplinary and orientalist cholera science that took shape in the 1860s and 1870s, which have, without renewed scrutiny, prevailed largely uncontested until recent decades. Those practices involved an over-interpretation of the historical epidemiological work of John Macpherson by his colleague N. C. Macnamara. Recent research, recognizing the wide distribution and genetic instability ofVibrio cholerae, offers an alternative context for appreciating Macpherson's insights. This new program of interdisciplinary cholera research seems largely free of stigmatizing representations, but nor does it offer (or seek) a single and simple program of cholera prevention. The cholera case study invites reflection on the little-studied problem of epistemic accountability in interdisciplinary research, alerts us to questions of how disciplines are (and might be) made to cohere in policy-driven inquiries. The chief maxim is toward more explicit inclusion of the concept of multiple working hypotheses. [ABSTRACT FROM PUBLISHER]

Background: Use of cholera vaccines in response to epidemics (reactive vaccination) may provide an effective supplement to traditional control measures. In Haiti, reactive vaccination was considered but, until recently, rejected in part due to limited global supply of vaccine. Using Bissau City, Guinea-Bissau as a case study, we explore neighborhood-level transmission dynamics to understand if, with limited vaccine and likely delays, reactive vaccination can significantly change the course of a cholera epidemic. Methods and Findings: We fit a spatially explicit meta-population model of cholera transmission within Bissau City to data from 7,551 suspected cholera cases from a 2008 epidemic. We estimated the effect reactive vaccination campaigns would have had on the epidemic under different levels of vaccine coverage and campaign start dates. We compared highly focused and diffuse strategies for distributing vaccine throughout the city. We found wide variation in the efficiency of cholera transmission both within and between areas of the city. "Hotspots", where transmission was most efficient, appear to drive the epidemic. In particular one area, Bandim, was a necessary driver of the 2008 epidemic in Bissau City. If vaccine supply were limited but could have been distributed within the first 80 days of the epidemic, targeting vaccination at Bandim would have averted the most cases both within this area and throughout the city. Regardless of the distribution strategy used, timely distribution of vaccine in response to an ongoing cholera epidemic can prevent cases and save lives. Conclusions: Reactive vaccination can be a useful tool for controlling cholera epidemics, especially in urban areas like Bissau City. Particular neighborhoods may be responsible for driving a city's cholera epidemic; timely and targeted reactive vaccination at such neighborhoods may be the most effective way to prevent cholera cases both within that neighborhood and throughout the city. Author Summary: Cholera remains a major public health threat, causing 3–5 million cases and 100,000–120,000 deaths each year. In 2010, data on vaccine performance and the changing epidemiology of cholera prompted the WHO's Strategic Advisory Group to recommend that reactive vaccination be considered in specific areas. We built a spatially explicit stochastic model of cholera transmission and fit it to data from a 2008 epidemic in Bissau City, Guinea Bissau. Using this model we examined the potential effectiveness of reactive vaccination for controlling cholera transmission in Bissau City, comparing strategies for distributing limited vaccine. In simulations, early targeting of a single transmission "hotspot", Bandim, was the most effective strategy, and led to the greatest reduction in cases both within Bandim and in areas where no vaccine was distributed. This finding has implications for cholera control in urban settings in general: public health officials will often know which areas of a city were hotspots of cholera transmission in the past or where conditions promote efficient transmission. When there is limited vaccine, our work suggests that targeting reactive vaccination at these areas will lead to the greatest reduction in cases both in these areas and elsewhere in the city. [ABSTRACT FROM AUTHOR]

Mathematical models can provide key insights into the course of an ongoing epidemic, potentially aiding real-time emergency management in allocating health care resources and by anticipating the impact of alternative interventions. We study the ex post reliability of predictions of the 2010-2011 Haiti cholera outbreak from four independent modeling studies that appeared almost simultaneously during the unfolding epidemic. We consider the impact of different approaches to the modeling of spatial spread of Vibrio cholerae and mechanisms of cholera transmission, accounting for the dynamics of susceptible and infected individuals within different local human communities. To explain resurgences of the epidemic, we go on to include waning immunity and a mechanism explicitly accounting for rainfall as a driver of enhanced disease transmission. The formal comparative analysis is carried out via the Akaike information criterion (AIC) to measure the added information provided by each process modeled, discounting for the added parameters. A generalized model for Haitian epidemic cholera and the related uncertainty is thus proposed and applied to the year-long dataset of reported cases now available. The model allows us to draw predictions on longer-term epidemic cholera in Haiti from multiseason Monte Carlo runs, carried out up to January 2014 by using suitable rainfall fields forecasts. Lessons learned and open issues are discussed and placed in perspective. We conclude that, despite differences in methods that can be tested through model-guided field validation, mathematical modeling of large-scale outbreaks emerges as an essential component of future cholera epidemic control. [ABSTRACT FROM AUTHOR]

Medical journals and other sources do not show evidence that cholera occurred in Haiti before 2010, despite the devastating effect of this disease in the Caribbean region in the 19th century. Cholera occurred in Cuba in 1833-1834; in Jamaica, Cuba, Puerto Rico, St. Thomas, St. Lucia, St. Kitts, Nevis, Trinidad, the Bahamas, St. Vincent, Granada, Anguilla, St. John, Tortola, the Turks and Caicos, the Grenadines (Carriacou and Petite Martinique), and possibly Antigua in 1850-1856; and in Guadeloupe, Cuba, St. Thomas, the Dominican Republic, Dominica, Martinique, and Marie Galante in 1865-1872. Conditions associated with slavery and colonial military control were absent in independent Haiti. Clustered populations, regular influx of new persons, and close quarters of barracks living contributed to spread of cholera in other Caribbean locations. We provide historical accounts of the presence and spread of cholera epidemics in Caribbean islands. [ABSTRACT FROM AUTHOR]

After epidemic cholera emerged in Haiti in October 2010, the disease spread rapidly in a country devastated by an earthquake earlier that year, in a population with a high proportion of infant deaths, poor nutrition, and frequent infectious diseases such as HIV infection, tuberculosis, and malaria. Many nations, multinational agencies, and nongovernmental organizations rapidly mobilized to assist Haiti. The US government provided emergency response through the Office of Foreign Disaster Assistance of the US Agency for International Development and the Centers for Disease Control and Prevention. This report summarizes the participation by the Centers and its partners. The efforts needed to reduce the spread of the epidemic and prevent deaths highlight the need for safe drinking water and basic medical care in such difficult circumstances and the need for rebuilding water, sanitation, and public health systems to prevent future epidemics. [ABSTRACT FROM AUTHOR]

This joint statement discusses the devastating impact of the cholera epidemic in Haiti, particularly after the 2010 earthquake. It emphasizes the need for a comprehensive strategy to address cholera, including case finding and treatment, strengthening water and sanitation infrastructure, and linking prevention to care. The document provides information on the epidemiology of cholera in Haiti and the challenges of a comprehensive response. Efforts to provide safe drinking water have been made, but poor sanitation conditions could lead to further transmission. The lack of access to safe water and sanitation has contributed to the cycle of poverty and ill health in Haiti. Prevention measures include vaccination campaigns and improving water and sanitation systems, but there are challenges to implementation. The document calls for the Haitian government to lead the response and for long-term financial support. The authors support a comprehensive and integrated approach to eliminate cholera in Haiti. [Extracted from the article]

Despite documented health benefits of household water treatment and storage (HWTS), achieving sustained use remains challenging. In prior evaluations of a long-term HWTS program in Haiti, multiple marketing interventions failed to increase use or had prohibitively high costs. Using mobile phones is a potentially cost-effective way to change HWTS behavior. We conducted a randomized experiment to evaluate the impact of sending short-message service (SMS) messages to promote household chlorination in this program in Haiti. Households (n = 1327) were randomly assigned to: One of four SMS frequencies; one of ten behavioral constructs; "cholera" or "disease" framing; and one or zero household visits from a sales agent. During the three-month campaign, there were no statistically significant relationships between the four outcomes related to chlorine purchases and any SMS frequency, any behavioral construct, or either "cholera" or "disease" framing. Receiving one visit increased the probability of purchasing a bottle of chlorine by 17.1 percentage points (p < 0.001) but did not affect subsequent purchase behavior. Costs of managing the SMS campaign were higher than expected. SMS campaigns may not be cost-effective behavior change interventions in certain contexts. If pursued, we recommend simple interventions, timed with the target behavior, and tailored to mobile phone usage patterns of the target population. [ABSTRACT FROM AUTHOR]

The article discusses the genomic diversity of 2010 cholera epidemic in Haiti. It discusses a study in which the examination of the genomes of Vibrio cholerae, causative agent of cholera isolates from Haitian patients with cholera was done to explore diversity within this species. The analysis of clinical samples from 81 patients suffering from cholera with varying severity is also discussed.

The article offers information on "The Bathers," an acrylic painting by Georges Desarmes featured in this issue of the journal. It notes that this painting highlights life on the Artibonite River, as well as nearby communities prior to the cholera outbreak in Haiti. Desarmes, born Yves Michaud and Port-au-Prince, started painting impressions of Haitian life in 2000. It characterizes the painting's scene as lyrical, spare, sunny and pre-cholera. It points out that cholera does not recognize false boundaries and highlights the frailties of political conflict, as well as the aftermath of mass travel and a rise in human contact.

The author reflects on the preparations and responses of humanity to cholera pandemic. The author discusses the global cholera situations in countries including Haiti, Pakistan, and Zimbabwe, which has severe latest occurrence of the outbreak. He states the responsibility of World Health Organization (WHO) in human health security, diseases control, and immunization efforts. He mentions the strategies such as cholera vaccination and long-term response plan in latest battle of human to cholera.