Kinetics of vibriocidal antibody responses among cholera patients in Goma, the Democratic Republic of Congo.

Cholera is a diarrheal disease that continues to burden vulnerable populations globally, primarily due to lack of clean water, optimal sanitation and adequate health infrastructure. Understanding the kinetics of antibody responses elicited by toxigenic infection can inform the Sero-epidemiological estimation of disease burden and impact of vaccination efforts. While antibody kinetics have been well-described in South Asia, such studies based in Africa are lacking, despite the ongoing prevalence of cholera in that region.

Coronavirus Disease 2019 Lineages in a Minimally Vaccinated Island Population: Genomic Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2 in Haiti.

We monitored severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants in Haiti from 2020 to 2023. Despite Haitian coronavirus disease 2019 (COVID-19) travel restrictions and in the setting of a vaccination rate of 2.7%, the timing and lineage evolution of the Haiti epidemic mirrored what was occurring in the rest of the world.

Seafood-Associated Outbreak of ctx-Negative Vibrio mimicus Causing Cholera-Like Illness, Florida, USA.

Vibrio mimicus caused a seafood-associated outbreak in Florida, USA, in which 4 of 6 case-patients were hospitalized; 1 required intensive care for severe diarrhea. Strains were ctx-negative but carried genes for other virulence determinants (hemolysin, proteases, and types I-IV and VI secretion systems). Cholera toxin-negative bacterial strains can cause cholera-like disease.

Ancestral Origin and Dissemination Dynamics of Reemerging Toxigenic Vibrio cholerae, Haiti.

The 2010 cholera epidemic in Haiti was thought to have ended in 2019, and the Prime Minister of Haiti declared the country cholera-free in February 2022. On September 25, 2022, cholera cases were again identified in Port-au-Prince. We compared genomic data from 42 clinical Vibrio cholerae strains from 2022 with data from 327 other strains from Haiti and 1,824 strains collected worldwide.

Spatial Video and EpiExplorer: A Field Strategy to Contextualize Enteric Disease Risk in Slum Environments.

Disease risk associated with contaminated water, poor sanitation, and hygiene in informal settlement environments is conceptually well understood. From an analytical perspective, collecting data at a suitably fine scale spatial and temporal granularity is challenging. Novel mobile methodologies, such as spatial video (SV), can complement more traditional epidemiological field work to address this gap.

Development of a Monoclonal Antibody to a Vibriophage as a Proxy for Vibrio cholerae Detection.

Cholera is an acute watery, diarrheal disease that causes high rates of morbidity and mortality without treatment. Early detection of the etiologic agent of toxigenic Vibrio cholerae is important to mobilize treatment and mitigate outbreaks. Monoclonal antibody (mAb) based rapid diagnostic tests (RDTs) enable early detection in settings without laboratory capacity.

Exploring convolutional neural networks and spatial video for on-the-ground mapping in informal settlements.

Background: The health burden in developing world informal settlements often coincides with a lack of spatial data that could be used to guide intervention strategies. Spatial video (SV) has proven to be a useful tool to collect environmental and social data at a granular scale, though the effort required to turn these spatially encoded video frames into maps limits sustainability and scalability. In this paper we explore the use of convolution neural networks (CNN) to solve this problem by automatically identifying disease related environmental risks in a series of SV collected from Haiti.

Draft Genome Sequence of an Environmental Vibrio cholerae Strain, 2012Env-25, Obtained Using Nanopore Sequencing Technology.

is a halophilic Gram-negative bacterial species and the etiological agent of cholera. Here, we report the draft genome sequence of an environmental strain, 2012Env-25, obtained using Oxford Nanopore Technologies (ONT) to provide insights into the ecology, evolution, and pathogenic potential of this bacterium.

Toxigenic evolution and establishment of reservoirs in aquatic ecosystems.

The spread of cholera in the midst of an epidemic is largely driven by direct transmission from person to person, although it is well-recognized that is also capable of growth and long-term survival in aquatic ecosystems. While prior studies have shown that aquatic reservoirs are important in the persistence of the disease on the Indian subcontinent, an epidemiological view postulating that locally evolving environmental contributes to outbreaks outside Asia remains debated. The single-source introduction of toxigenic O1 in Haiti, one of the largest outbreaks occurring this century, with 812,586 suspected cases and 9,606 deaths reported through July 2018, provided a unique opportunity to evaluate the role of aquatic reservoirs and assess bacterial transmission dynamics across environmental boundaries.

Conversion of a -Mediated Non-toxigenic O1 Strain to a Toxigenic Strain Using Chitin-Induced Transformation.

Toxigenic strains, including strains in serogroups O1 and O139 associated with the clinical disease cholera, are ubiquitous in aquatic reservoirs, including fresh, estuarine, and marine environments. Humans acquire cholera by consuming water and/or food contaminated with the microorganism. The genome of toxigenic harbors a cholera-toxin producing prophage (CT-prophage) encoding genes that promote expression of cholera toxin.

Acute Respiratory Illness in Rural Haiti.

Objectives: Acute Respiratory Infection (ARI) is the most common cause of childhood morbidity and mortality in developing countries, including Haiti. Our objective was to detect pathogens found in children with ARI in rural Haiti to help develop evidence-based guidelines for treatment and prevention.

Methods: Retrospective study of students with ARI at four schools in rural Haiti.

Non-toxigenic environmental Vibrio cholerae O1 strain from Haiti provides evidence of pre-pandemic cholera in Hispaniola.

Vibrio cholerae is ubiquitous in aquatic environments, with environmental toxigenic V. cholerae O1 strains serving as a source for recurrent cholera epidemics and pandemic disease. However, a number of questions remain about long-term survival and evolution of V.

Major Shift of Toxigenic V. cholerae O1 from Ogawa to Inaba Serotype Isolated from Clinical and Environmental Samples in Haiti.

In October of 2010, an outbreak of cholera was confirmed in Haiti for the first time in more than a century. A single clone of toxigenic Vibrio cholerae O1 biotype El Tor serotype Ogawa strain was implicated as the cause. Five years after the onset of cholera, in October, 2015, we have discovered a major switch (ranging from 7 to 100%) from Ogawa serotype to Inaba serotype.

Genetic Studies of Vibrio cholerae in South West Cameroon-A Phylogenetic Analysis of Isolates from the 2010-2011 Epidemic.

Introduction: During the cholera outbreak from 2010 to 2011 in Cameroon, 33,192 cases with 1,440 deaths (case fatality ratio 4.34%) were reported to the World Health Organization. Of these, the South West Region reported 3,120 clinical cases.

Mapping to Support Fine Scale Epidemiological Cholera Investigations: A Case Study of Spatial Video in Haiti.

The cartographic challenge in many developing world environments suffering a high disease burden is a lack of granular environmental covariates suitable for modeling disease outcomes. As a result, epidemiological questions, such as how disease diffuses at intra urban scales are extremely difficult to answer. This paper presents a novel geospatial methodology, spatial video, which can be used to collect and map environmental covariates, while also supporting field epidemiology.

Stx-Producing Shigella Species From Patients in Haiti: An Emerging Pathogen With the Potential for Global Spread.

Shiga toxins (Stx) are commonly produced by Shigella dysenteriae serotype 1 and Stx-producing Escherichia coli. However, the toxin genes have been detected in additional Shigella species. We recently reported the emergence of Stx-producing Shigella in travelers in the United States and France who had recently visited Hispaniola (Haiti and the Dominican Republic).

Increased isolation frequency of toxigenic Vibrio cholerae O1 from environmental monitoring sites in Haiti.

Since the identification of the first cholera case in 2010, the disease has spread in epidemic form throughout the island nation of Haiti; as of 2014, about 700,000 cholera cases have been reported, with over 8,000 deaths. While case numbers have declined, the more fundamental question of whether the causative bacterium, Vibrio cholerae has established an environmental reservoir in the surface waters of Haiti remains to be elucidated. In a previous study conducted between April 2012 and March 2013, we reported the isolation of toxigenic V.

Phylodynamic analysis of clinical and environmental Vibrio cholerae isolates from Haiti reveals diversification driven by positive selection.

Unlabelled: Phylodynamic analysis of genome-wide single-nucleotide polymorphism (SNP) data is a powerful tool to investigate underlying evolutionary processes of bacterial epidemics. The method was applied to investigate a collection of 65 clinical and environmental isolates of Vibrio cholerae from Haiti collected between 2010 and 2012. Characterization of isolates recovered from environmental samples identified a total of four toxigenic V.

High-frequency rugose exopolysaccharide production by Vibrio cholerae strains isolated in Haiti.

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.

Feasibility of the hydrogen sulfide test for the assessment of drinking water quality in post-earthquake Haiti.

In 2010, a magnitude 7.0 earthquake struck Haiti, severely damaging the drinking and wastewater infrastructure and leaving millions homeless. Compounding this problem, the introduction of Vibrio cholerae resulted in a massive cholera outbreak that infected over 700,000 people and threatened the safety of Haiti's drinking water.

Water-related infrastructure in a region of post-earthquake Haiti: high levels of fecal contamination and need for ongoing monitoring.

We inventoried non-surface water sources in the Leogane and Gressier region of Haiti (approximately 270 km(2)) in 2012 and 2013 and screened water from 345 sites for fecal coliforms and Vibrio cholerae. An international organization/non-governmental organization responsible for construction could be identified for only 56% of water points evaluated. Sixteen percent of water points were non-functional at any given time; 37% had evidence of fecal contamination, with spatial clustering of contaminated sites.

Diarrhea in young children from low-income countries leads to large-scale alterations in intestinal microbiota composition.

Background: Diarrheal diseases continue to contribute significantly to morbidity and mortality in infants and young children in developing countries. There is an urgent need to better understand the contributions of novel, potentially uncultured, diarrheal pathogens to severe diarrheal disease, as well as distortions in normal gut microbiota composition that might facilitate severe disease.

Results: We use high throughput 16S rRNA gene sequencing to compare fecal microbiota composition in children under five years of age who have been diagnosed with moderate to severe diarrhea (MSD) with the microbiota from diarrhea-free controls.

Prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Ouest and Sud-Est departments of Haiti.

Malaria remains a significant public health issue in Haiti, with chloroquine (CQ) used almost exclusively for the treatment of uncomplicated infections. Recently, single dose primaquine (PQ) was added to the Haitian national malaria treatment policy, despite a lack of information on the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency within the population. G6PD deficient individuals who take PQ are at risk of developing drug induced hemolysis (DIH).