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Neurons are complex cells with two distinct compartments: the somatodendritic and the axonal domains. Because of their polarized morphology, it is challenging to study the differential cellular and molecular mechanisms that occur in axons and impact the soma and dendrites using conventional in vitro culture systems. Compartmentalized cultures offer a solution by physically and chemically separating the axonal from the somatodendritic domain of neurons. The microfluidic chamber model presented in this work is valuable for studying these mechanisms in primary cortical cultures derived from rat and mouse. In addition, this chamber model is compatible with various microscopy methods, such as phase contrast, and fluorescence imaging of living and fixed cells. Key features • Preparation and attachment of PDMS microfluidic chambers to glass coverslips. • Primary culture of cortical neurons and plating cortical neurons in microfluidic chamber. • Confirmation of compartmentalization using the retrograde transport of the fluorescently labeled form of cholera toxin subunit B (f-Ctb). • Immunofluorescence and multilabeling of compartmentalized cortical neurons. • Retrograde transport of fluorescently labeled BDNF.

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BACKGROUNDS: This study assesses the impact of Water, Sanitation, and Hygiene (WASH) interventions on cholera understanding and hygiene practices in La Gonâve Island, Haiti. It examines the changes after implementing interventions in seven villages across the Downtown, Mountain, and Seaside regions. METHODS: A retrospective investigation surveyed 210 school students from each region using a validated questionnaire. It assessed knowledge, attitudes, practices (KAP), and environmental aspects related to cholera and hygiene. Data analysis involved descriptive statistics and chi-square tests. RESULTS: The study highlights significant disparities in education levels, toilet ownership, and healthcare access. Challenges in finding public toilets (86.67%) and accessing water sources (67.78%) are consistent across regions, with Seaside facing financial constraints (85.00%) and water cost concerns (91.67%). Attitudes toward hygiene vary, with the Mountain region having the highest 'Never' responses for handwashing (38.89%), and Downtown leading in water treatment practices (11.67%). There is a strong willingness to share health knowledge, particularly in Downtown (100.00%). Seaside (83.33%) and Downtown (73.33%) revealed a higher cholera awareness, while nearly half of Mountain students lacked knowledge (54.44%). CONCLUSIONS: This study highlights significant disparities in WASH practices among La Gonâve's adolescents in Downtown, Mountain, and Seaside regions. Urgent interventions are crucial for improving sanitation, ensuring clean water access, and implementing targeted hygiene education, especially in the resource-constrained Mountain and Seaside areas. The findings underscore the vital roles of adolescents and schools in disseminating knowledge, with further research needed to explore intervention differences.

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OBJECTIVES: The World Health Organization recommends the use of oral cholera vaccine (OCV) in cholera control efforts. Euvichol®, pre-qualified in 2015, is the leading component of the Global OCV stockpile, but data on its field effectiveness are limited. To evaluate Euvichol® vaccine effectiveness (VE), we conducted a case-control study between September 2018 to March 2020 following an OCV campaign in November 2017 in Haiti. METHODS: Cases were individuals with acute watery diarrhea. Stool samples were tested by culture and real-time polymerase chain reaction of the Vibrio cholerae ctxA gene. Cases were matched to four community controls without diarrhea by residence, enrollment time, age, and gender, and interviewed for sociodemographics, risk factors, and self-reported vaccination. Cholera cases were analyzed by conditional logistic regression in the VE study. Non-cholera diarrhea cases were analyzed in a bias-indicator study. RESULTS: We enrolled 15 cholera cases matched to 60 controls, and 63 non-cholera diarrhea cases matched to 249 controls. In the VE analysis, eight (53%) cases reported vaccination with any number of doses compared to 43 (72%) controls. Adjusted two-dose OCV VE was 69% (95% CI -71 to 94%). CONCLUSIONS: Between 10-27 months after vaccination, Euvichol® was effective and similar to Shanchol™, suggesting that it can serve as one component of multi-sectoral comprehensive cholera control.

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Vibriosis and cholera are serious diseases distributed worldwide and caused by six marine bacteria of the Vibrio genus. Thousands of deaths occur each year due to these illnesses, necessitating the development of new preventive measures. Presently, the existing cholera vaccine demonstrates an effectiveness of approximately 60%. Here we describe a new multi-epitope vaccine, 'vme-VAC/MST-1' based on vaccine targets identified by reverse vaccinology and epitopes predicted by immunoinformatics, two currently effective tools for predicting new vaccines for bacterial pathogens. The vaccine was designed to combat vibriosis and cholera by incorporating epitopes predicted for CTL, HTL, and B cells. These epitopes were identified from six vaccine targets revealed through subtractive genomics, combined with reverse vaccinology, and were further filtered using immunoinformatics approaches based on their predicted immunogenicity. To construct the vaccine, 28 epitopes (24 CTL/B and 4 HTL/B) were linked to the sequence of the cholera toxin B subunit adjuvant. In silico analyses indicate that the resulting immunogen is stable, soluble, non-toxic, and non-allergenic. Furthermore, it exhibits no homology to the host and demonstrates a strong capacity to elicit innate, B-cell, and T-cell immune responses. Our analysis suggests that it is likely to elicit immune reactions mediated through the TLR5 pathway, as evidenced by the molecular docking of the vaccine with the receptor, which revealed high affinity and a favorable reaction. Thus, vme-VAC/MST-1 is predicted to be a safe and effective solution against pathogenic Vibrio spp. However, further experimental analyses are required to measure the vaccine's effects In vivo.Communicated by Ramaswamy H. Sarma.

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The present study evaluated the role of heme oxygenase 1 (HO-1)/carbon monoxide (CO) pathway in the cholera toxin-induced diarrhea and its possible action mechanism. The pharmacological modulation with CORM-2 (a CO donor) or Hemin (a HO-1 inducer) decreased the intestinal fluid secretion and Cl- efflux, altered by cholera toxin. In contrast, ZnPP (a HO-1 inhibitor) reversed the antisecretory effect of Hemin and potentiated cholera toxin-induced intestinal secretion. Moreover, CORM-2 also prevented the alteration of intestinal epithelial architecture and local vascular permeability promoted by cholera toxin. The intestinal absorption was not altered by any of the pharmacological modulators. Cholera toxin inoculation also increased HO-1 immunoreactivity and bilirubin levels, a possible protective physiological response. Finally, using fluorometric technique, ELISA assay and molecular docking simulations, we show evidence that CO directly interacts with cholera toxin, forming a complex that affects its binding to GM1 receptor, which help explain the antisecretory effect. Thus, CO is an essential molecule for protection against choleric diarrhea and suggests its use as a possible therapeutic tool.

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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. The 2022 isolates were homogeneous and closely related to clinical and environmental strains circulating in Haiti during 2012-2019. Bayesian hypothesis testing indicated that the 2022 clinical isolates shared their most recent common ancestor with an environmental lineage circulating in Haiti in July 2018. Our findings strongly suggest that toxigenic V. cholerae O1 can persist for years in aquatic environmental reservoirs and ignite new outbreaks. These results highlight the urgent need for improved public health infrastructure and possible periodic vaccination campaigns to maintain population immunity against V. cholerae.

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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.

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Resumen El hospital Muñiz es una institución con patrimonio histórico, cultural y sanitario. Se realiza aquí un análisis histórico de las diferentes epidemias/pandemias y bro tes, valorando los manejos epidemiológicos (vigilancia, prevención, control y gestión de emergencias) en la institución y el porqué de su arquitectura. Para tal fin se lleva a cabo una revisión sistemática de la literatura sobre la historia del hospital Muñiz y sus referentes desde 1980 hasta 2023, siguiendo el formato PRISMA. Se encontraron 36 publicaciones que cumplieron con los criterios metodológicos y epidemiológicos requeridos. La revisión muestra los problemas relevantes en salud, los eventos presentes en una epidemia/pandemia, la importancia de medidas de prevención y de evaluar la necesidad de un sistema de vigilancia epidemiológica continuo, así como el aporte de referentes históricos metodológicos que permita obtener información útil en el área de salud. Hemos abordado grandes momentos históricos en la epidemiología explicando el manejo de las enfermedades o epidemias/pandemias en el hospital Muñiz, las cuales se relacionaron en gran medida a la sociedad de la época (paradigmas). Cabe resaltar que el crecimiento poblacional extendió las enfermedades a lo largo del planeta generando amenazas y que las epide mias/pandemias transformaron las sociedades y muy posiblemente han cambiado decisivamente el curso de la historia, tal como paso con la pandemia por COVID-19.

Abstract The Muñiz hospital is an institution with historical, cultural and health heritage. A historical analysis of the different epidemics/pandemics and outbreaks is carried out here, assessing the epidemiological man agement (surveillance, prevention, control and emer gency management) in the institution and the reason for its architecture. To this end, a systematic review of the literature on the history of the Muñiz hospital and its references was carried out, since 1980 to 2023, following the PRISMA format. Thirty-six publications were found that met the required methodological and epidemiological criteria. The review shows the relevant health problems, the events present in an epidemic/ pandemic, the importance of preventive measures and to assess the need for a continuous epidemiological surveillance system, as well as the contribution of historical methodological references that allow obtaining useful information in the health area. We have addressed great historical moments in epidemiology, explaining the management of diseases or epidemics/pandemics at the Muñiz hospital, which were largely related to the society of the time (paradigms). It should be noted that population growth spread diseases throughout the planet, generating threats, and that epidemics/pan demics transformed societies and quite possibly have decisively changed the course of history, as happened with the COVID-19 pandemic.

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A Vibrio cholerae O1 outbreak emerged in Haiti in October 2022 after years of cholera absence. In samples from a 2021 serosurvey, we found lower circulating antibodies against V. cholerae lipopolysaccharide in children <5 years of age and no vibriocidal antibodies, suggesting high susceptibility to cholera, especially among young children.

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We report on the sensitivity and specificity of stool culture compared to polymerase chain reaction for detecting Vibrio cholerae in Haiti during the waning period of the initial outbreak in 2018-2019. We found that stool culture (with a sensitivity of 33.3% and specificity of 97.4%) may not be sufficiently robust in this context.

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The Muñiz hospital is an institution with historical, cultural and health heritage. A historical analysis of the different epidemics/pandemics and outbreaks is carried out here, assessing the epidemiological management (surveillance, prevention, control and emergency management) in the institution and the reason for its architecture. To this end, a systematic review of the literature on the history of the Muñiz hospital and its references was carried out, since 1980 to 2023, following the PRISMA format. Thirty-six publications were found that met the required methodological and epidemiological criteria. The review shows the relevant health problems, the events present in an epidemic/ pandemic, the importance of preventive measures and to assess the need for a continuous epidemiological surveillance system, as well as the contribution of historical methodological references that allow obtaining useful information in the health area. We have addressed great historical moments in epidemiology, explaining the management of diseases or epidemics/pandemics at the Muñiz hospital, which were largely related to the society of the time (paradigms). It should be noted that population growth spread diseases throughout the planet, generating threats, and that epidemics/pandemics transformed societies and quite possibly have decisively changed the course of history, as happened with the COVID-19 pandemic.

El hospital Muñiz es una institución con patrimonio histórico, cultural y sanitario. Se realiza aquí un análisis histórico de las diferentes epidemias/pandemias y brotes, valorando los manejos epidemiológicos (vigilancia, prevención, control y gestión de emergencias) en la institución y el porqué de su arquitectura. Para tal fin se lleva a cabo una revisión sistemática de la literatura sobre la historia del hospital Muñiz y sus referentes desde 1980 hasta 2023, siguiendo el formato PRISMA. Se encontraron 36 publicaciones que cumplieron con los criterios metodológicos y epidemiológicos requeridos. La revisión muestra los problemas relevantes en salud, los eventos presentes en una epidemia/pandemia, la importancia de medidas de prevención y de evaluar la necesidad de un sistema de vigilancia epidemiológica continuo, así como el aporte de referentes históricos metodológicos que permita obtener información útil en el área de salud. Hemos abordado grandes momentos históricos en la epidemiología explicando el manejo de las enfermedades o epidemias/pandemias en el hospital Muñiz, las cuales se relacionaron en gran medida a la sociedad de la época (paradigmas). Cabe resaltar que el crecimiento poblacional extendió las enfermedades a lo largo del planeta generando amenazas y que las epidemias/ pandemias transformaron las sociedades y muy posiblemente han cambiado decisivamente el curso de la historia, tal como paso con la pandemia por COVID-19.

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Vibrio cholerae is the causative agent of cholera, a highly contagious diarrheal disease affecting millions worldwide each year. Cholera is a major public health problem, primarily in countries with poor sanitary conditions and regions affected by natural disasters, where access to safe drinking water is limited. In this narrative review, we aim to summarize the current understanding of the evolution of virulence and pathogenesis of V. cholerae as well as provide an overview of the immune response against this pathogen. We highlight that V. cholerae has a remarkable ability to adapt and evolve, which is a global concern because it increases the risk of cholera outbreaks and the spread of the disease to new regions, making its control even more challenging. Furthermore, we show that this pathogen expresses several virulence factors enabling it to efficiently colonize the human intestine and cause cholera. A cumulative body of work also shows that V. cholerae infection triggers an inflammatory response that influences the development of immune memory against cholera. Lastly, we reviewed the status of licensed cholera vaccines, those undergoing clinical evaluation, and recent progress in developing next-generation vaccines. This review offers a comprehensive view of V. cholerae and identifies knowledge gaps that must be addressed to develop more effective cholera vaccines.

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After three years with no confirmed cholera cases in Haiti, an outbreak of Vibrio cholerae O1 emerged in October 2022. Levels of pre-existing antibodies provide an estimate of prior immunologic exposure, reveal potentially relevant immune responses, and set a baseline for future serosurveillance. We analyzed dried blood spots collected in 2021 from a population-weighted representative cross-sectional serosurvey in two communes in the Ouest Department of Haiti. We found lower levels of circulating IgG and IgA antibodies against V. cholerae lipopolysaccharide (LPS, IgG and IgA p<0.0001) in those below 5 years of age compared to those five years and older. Among a subset of patients with higher titers of antibodies, we were unable to detect any functional (vibriocidal) antibodies. In conclusion, the lack of detectable functional antibodies, and age-discordant levels of V. cholerae LPS IgG, suggest that populations in Haiti may be highly susceptible to cholera disease, especially among young children.

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Toxigenic Vibrio cholerae O1 serotype Ogawa was introduced involuntarily into Haiti in October 2010, and virtually all of the clinical strains isolated during the first 5 years of the epidemic were Ogawa. Inaba strains were identified intermittently prior to 2015, with diverse mutations resulting in a common phenotype. In 2015, the percentage of clinical infections due to the Inaba serotype began to rapidly increase, with Inaba supplanting Ogawa as the dominant serotype during the subsequent 4 years. We investigated the molecular basis of the serotype switch and confirmed that all Inaba strains had the same level of mRNA expression of the wbeT genes, as well as the same translation levels for the truncated WbeT proteins in the V. cholerae Inaba isolates. Neither wbeT gene expression levels, differential mutations, or truncation size of the WbeT proteins appeared to be responsible for the successful Inaba switch in 2015. Our phylodynamic analysis demonstrated that the V. cholerae Inaba strains in Haiti evolved directly from Ogawa strains and that a significant increase of diversifying selection at the population level occurred at the time of the Ogawa-Inaba switch. We conclude that the emergence of the Inaba serotype was driven by diversifying selection, independent of the mutational pattern in the wbeT gene. IMPORTANCE Our phylodynamic analysis demonstrated that Vibrio cholerae Inaba strains in Haiti evolved directly from Ogawa strains. Our results support the hypothesis that after an initial Ogawa-dominated epidemic wave, V. cholerae Inaba was able to become the dominant strain thanks to a selective advantage driven by ongoing diversifying selection, independently from the mutational pattern in the wbeT gene.

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INTRODUCTION: Vibrio cholerae is a microorganism that causes acute diarrheal diseases and cholera, one of the leading causes of global morbidity and mortality, especially in children under five years old. It is present in many regions and has been isolated from diverse sources such as water, soil and food. Surveillance of this microorganism in Cuba from 1985 through June 1997 showed circulation of non-epidemic non-O1/non-O139 serogroups, but surveillance continued to identify distribution of V. cholerae serotypes and serogroups in the different geographic regions of the country during the following years, due to the risk of introducing cholera-causing serogroups that provoked cholera epidemics in other countries of the region. OBJECTIVE: Describe the temporal‒spatial distribution of serogroups and serotypes of V. cholerae in Cuba. METHODS: A cross-sectional study was conducted that included isolates from passive surveillance of V. cholerae in 16 hygiene and epidemiology centers throughout Cuba from July 1997 through December 2019, submitted to the National Reference Laboratory for Acute Diarrheal Diseases of the Pedro Kourí Tropical Medicine Institute in Havana, Cuba. The timeline was subdivided into three five-year periods and one eight-year period. The centers submitting isolates were grouped into three geographical regions: western, central and eastern Cuba. A total of 1060 V. cholerae isolates were studied, from the 1438 samples sent from 15 Provincial Hygiene, Epidemiology and Microbiology Centers and the Municipal Hygiene, Epidemiology and Microbiology Center of the Isle of Youth Special Municipality. Genus, species and serotype of all specimens were studied and reviewed in the context of the outbreaks of acute diarrheal diseases reported in the country. RESULTS: All 1060 isolates were confirmed as V. cholerae. In the distribution by time period and region, the highest percentage occurred in the 2012‒2019 period, and the eastern region contributed the most isolates in all periods. Approximately 63.9% (677/1060) were from outbreaks, and in the 2012‒2019 period, the most epidemic-causing isolates came from the western region. Approximately 52.8% (560/1060) were identified as non-O1/non-O139 V. cholerae, and 47.2% (500/1060) as O1 V. cholerae; of these, 96.4% (482/500) corresponded to Ogawa serotype and 3.6% (18/500) to Inaba. Circulation of non-O1/non-O139 V. cholerae occurred throughout the entire period. The O1 serogroup began to circulate in 2012 and continued through 2016; however, since 2017, it has not been identified again. In the western region, there were smaller percentages of isolates of non-O1/non-O139 V. cholerae in all periods, except 2012‒2019. In that period, V. cholerae O1 was identified to a lesser degree in the central region. CONCLUSIONS: Vibrio cholerae circulated in all three Cuban regions during the years studied, with a higher percentage of isolates of the non-O1/non-O139 serogroup, which caused outbreaks or sporadic cases of diarrhea in the eastern region, with the exception of the 2012‒2019 period, when epidemic outbreaks of the O1 serogroup (which causes cholera) occurred in all three regions, with higher percentages in the western region.

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Vibrio cholerae causes cholera and can switch between planktonic and biofilm lifeforms, where biofilm formation enhances transmission, virulence, and antibiotic resistance. Due to antibiotic microbial resistance, new antimicrobials including silver nanoparticles (AgNPs) are being studied. Nevertheless, little is known about the metabolic changes exerted by AgNPs on both microbial lifeforms. Our objective was to evaluate the changes in the metabolomic profile of V. cholerae planktonic and biofilm cells in response to sublethal concentrations of AgNPs using MS2 untargeted metabolomics and chemoinformatics. A total of 690 metabolites were quantified among all groups. More metabolites were significantly modulated in planktonic cells (n = 71) compared to biofilm (n = 37) by the treatment. The chemical class profiles were distinct for both planktonic and biofilm, suggesting a phenotype-dependent metabolic response to the nanoparticles. Chemical enrichment analysis showed altered abundances of oxidized fatty acids (FA), saturated FA, phosphatidic acids, and saturated stearic acid in planktonic cells treated with AgNPs, which hints at a turnover of the membrane. In contrast, no chemical classes were enriched in the biofilm. In conclusion, this study suggests that the response of V. cholerae to silver nanoparticles is phenotype-dependent and that planktonic cells experience a lipid remodeling process, possibly related to an adaptive mechanism involving the cell membrane.

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AIMS: The present study aimed to document the comparative analysis of differential hypervirulent features of Vibrio cholerae O1 strains isolated during 2018 from cholera endemic regions in Gujarat and Maharashtra (Western India) and West Bengal (Eastern India). METHODS AND RESULTS: A total of 87 V. cholerae O1 clinical strains from Western India and 48 from Eastern India were analysed for a number of biotypic and genotypic features followed by antimicrobial resistance (AMR) profile. A novel polymerase chain reaction was designed to detect a large fragment deletion in the Vibrio seventh pandemic island II (VSP-II) genomic region, which is a significant genetic feature of the V. cholerae strains that have caused Yemen cholera outbreak. All the strains from Western India belong to the Ogawa serotype, polymyxin B-sensitive, hemolytic, had a deletion in VSP-II (VSP-IIC) region and carried Haitian genetic alleles of ctxB, tcpA and rtxA. Conversely, 14.6% (7/48) of the strains from Eastern India belonged to the Inaba serotype, polymyxin B-resistant, nonhemolytic, harboured VSP-II other than VSP-IIC type, classical ctxB, Haitian tcpA and El Tor rtxA alleles. Resistance to tetracycline and chloramphenicol has been observed in strains from both regions. CONCLUSIONS: This study showed hypervirulent, polymyxin B-sensitive epidemic causing strains in India along with the strains with polymyxin B-resistant and nonhemolytic traits that may spread and cause serious disease outcomes in future. SIGNIFICANCE AND IMPACT OF THE STUDY: The outcomes of this study can help to improve the understanding of the hyperpathogenic property of recently circulating pandemic Vibrio cholerae strains in India. Special attention is also needed for the monitoring of AMR surveillance because V. cholerae strains are losing susceptibility to many antibiotics used as a second line of defence in the treatment of cholera.

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BACKGROUND: Immunization is the key to prevent invasive meningococcal disease (IMD), caused by Neisseria meningitidis. Outer membrane vesicles (OMVs) can be used as meningococcal antigens. METHODS: Isogenic mice A/Sn (H2a) were immunized with low antigenic doses of OMVs of an N. meningitidis C:2a:P1.5 strain, via intranasal/intramuscular route, adjuvanted by cholera toxin subunit B (CTB) or via intramuscular route only, adjuvanted by aluminium hydroxide (AH). Mice were followed until old age and humoral and cellular responses were assessed by ELISA, Immunoblotting, Dot-blot, Serum-bactericidal assay, Immunohistochemistry and ELISpot. RESULTS: OMV+CTB and OMV+AH groups presented statistically higher antibodies titers, which persisted until middle and old ages. IgG isotypes point to a Th2 type of response. Avidity indexes were considered high, regardless of adjuvant use, but only groups immunized with OMVs and adjuvants (OMV+CTB and OMV+AH) presented bactericidal activity. The antibodies recognized antigens of molecular weights attributed to porin and cross-reactivity proteins. Although the spleen of old mice did not present differences in immunohistochemistry marking of CD68+, CD4+, CD79+ and CD25+ cells, splenocytes of immune groups secreted IL-4 and IL-17 when stimulated with OMVs and meningococcal C polysaccharide. CONCLUSION: We concluded that both adjuvants, CTB and AH, improved the immunogenicity of low doses of OMVs and contributed to a persistent immune response. Even though AH is well established in the vaccinology area, CTB seems to be a promising adjuvant candidate for meningococcal vaccines: it is suitable for mucosal delivery and supports a Th2 type of response. Therefore, OMVs are still a relevant vaccine platform.

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