Collaboration in the midst of chaos: perspectives of inpatient occupational and physical therapists during the COVID-19 pandemic.

The COVID-19 pandemic has affected over 700 million people globally, straining healthcare systems and highlighting the need for interprofessional collaboration. The aim of this study was to describe interprofessional collaborative practice (IPCP) experiences from the perspectives of occupational therapists (OTs) and physical therapists (PTs) who were employed in a medical center both before and during the COVID-19 pandemic. This qualitative study, conducted from July 2020-November 2021, delved into the lived experiences of occupational and physical therapists in an inpatient setting during the pandemic through analysis of semi-structured interviews and journal entries. The pandemic prompted fear, uncertainty, and ethical dilemmas among therapists, affecting patient-centered care. Roles expanded, and teamwork challenges emerged in defining boundaries, while communication dynamics were transformed by virtual technologies. The pandemic affected therapists' values and ethics, and evolving roles brought expanded tasks. The crisis showcased both collaboration potential and the need to address team disparities. This study highlights the significance of values, roles, teams, and communication for occupational and physical therapists during the COVID-19 pandemic providing valuable insights into interprofessional collaboration's effect on healthcare delivery in times of crisis and beyond.

Implementation and Mixed-Methods Assessment of an Early Mobility Interprofessional Education Simulation.

INTRODUCTION: Extended periods of bed rest and mechanical ventilation (MV) have devastating effects on the body. BACKGROUND: Early mobility (EM) for patients in respiratory failure is safe and feasible, and an interprofessional team is recommended. Using simulation to train EM skills improves student confidence. The purpose of this study was to enable health care student collaboration as an interprofessional team in providing safe management and monitoring during an EM simulation for a patient requiring MV. METHODS: Nursing (n = 33), respiratory (n = 7), occupational (n = 24), and physical therapist students (n = 55) participated in an EM interprofessional education (IPE) simulation experience. A mixed-methods analytic approach was used with pre/post quantitative analysis of the Student Perceptions of Interprofessional Clinical Education-Revised, Version 2 instrument and qualitative analysis of students' guided reflection papers. RESULTS: Pre/post surveys completion rate was 39.5% (n = 47). The Student Perceptions of Interprofessional Clinical Education-Revised, Version 2 instrument indicated a significant improvement (P = .037) in students' perceptions of interprofessional collaborative practice. Qualitative data showed a positive response to the EM simulation IPE. Themes reflected all 4 Interprofessional Education Collaborative competencies. DISCUSSION: This study demonstrated improved perception of interprofessional collaborative practice and better understanding of the Interprofessional Education Collaborative competencies. CONCLUSION: Students collaborated in the simulation-based IPE to provide EM for a patient requiring MV and reported perceived benefits of the experience.

Virtual Interprofessional Education: Team Collaboration in Discharge Planning Simulation.

PURPOSE OF STUDY: This study assessed the effectiveness of a virtual interprofessional education (IPE) discharge planning simulation, focusing on collaborative patient education, and recommendations for hospital discharge. PRIMARY PRACTICE SETTING: An acute care hospital. METHODOLOGY AND SAMPLE: The study utilized a virtual IPE discharge planning simulation for health care students from six different programs. The simulation involved prebriefing, icebreaker, team meeting, patient interaction, and debriefing. Assessment included pre- and post-IPE surveys that included the Interprofessional Education Collaborative (IPEC) Competency Self-Assessment Tool, and video analysis using the Modified McMaster-Ottawa Rating Scale. RESULTS: Student participants from diverse health care programs (n =143) included nursing (n = 20), occupational therapy (n = 21), physical therapy (n = 42), physician assistant (n = 38), respiratory therapy (n = 3), and social work (n = 19). All programs except respiratory therapy showed significant improvement in IPEC Competency scores post-IPE, with positive outcomes for understanding other professions' roles. Students' self-reported perceptions of team performance were rated highly in various categories. Video analysis demonstrated strong interrater reliability for team scores. IMPLICATIONS FOR CASE MANAGEMENT PRACTICE: Effective hospital discharge planning is vital for cost reduction and patient care improvement. IPE emphasizes collaborative learning among health care students. Previous studies highlight positive outcomes from IPE discharge planning, including virtual formats. This virtual IPE discharge planning simulation significantly improved students' understanding and collaboration competencies, evident in increased IPEC scores across five professions.

The Impact of COVID-19 on Interprofessional Collaborative Practice Through the Lens of Acute Care Physical Therapists: A Case Series.

This case report describes interprofessional collaborative practice experiences through the viewpoints of 3 acute care physical therapists who worked with patients with coronavirus disease-2019 (COVID-19) during the early months of the pandemic. Methods: The cases presented in this case report were selected from a larger longitudinal qualitative multiple-case study investigating interprofessional collaborative practice experiences of physical therapists employed in inpatient settings prior to and during the pandemic. The cases provide detailed narrative descriptions of interprofessional collaborative practice before and during the pandemic from the perspective of 3 physical therapists working in acute care environments. Results: The 3 physical therapists reported challenges to and opportunities for interprofessional collaborative practices that align with the 4 interprofessional educational competencies (values/ethics, roles/responsibilities, communication, and teams/teamwork). Conclusions: The ability to provide patient-centered care through interprofessional collaborative practices was impacted by the COVID-19 pandemic. The rich narrative descriptions of our participants' experiences as members of interprofessional teams provide additional insight regarding the effect of the COVID-19 pandemic on interprofessional collaborative practice.

Convergence to precipitating quasi-geostrophic equations with phase changes: asymptotics and numerical assessment.

The quasi-geostrophic (QG) equations play a crucial role in our understanding of atmospheric and oceanic fluid dynamics. Nevertheless, the traditional QG equations describe 'dry' dynamics that do not account for moisture and clouds. To move beyond the dry setting, precipitating QG (PQG) equations have been derived recently using formal asymptotics. Here, we investigate whether the moist Boussinesq equations with phase changes will converge to the PQG equations. A priori, it is possible that the nonlinearity at the phase interface (cloud edge) may complicate convergence. A numerical investigation of convergence or non-convergence is presented here. The numerical simulations consider cases of [Formula: see text], 0.01 and 0.001, where [Formula: see text] is proportional to the Rossby and Froude numbers. In the numerical simulations, the magnitude of vertical velocity [Formula: see text] (or other measures of imbalance and inertio-gravity waves) is seen to be approximately proportional to [Formula: see text] as [Formula: see text] decreases, which suggests convergence to PQG dynamics. These measures are quantified at a fixed time [Formula: see text] that is [Formula: see text], and the numerical data also suggests the possibility of convergence at later times. This article is part of the theme issue 'Mathematical problems in physical fluid dynamics (part 2)'.

Using Interprofessional Simulation with Telehealth to Enhance Teamwork and Communication in Home Care.

Interpersonal communication and teamwork are critical to patient safety. There is evidence supporting the effectiveness of formalized team training strategies such as simulation-based learning experiences to permit opportunities for deliberate practice and skill acquisition. However, there is a paucity of evidence examining the best method for delivery of simulation-based interprofessional education activities (Sim-IPE). The purpose of this project was to explore the effectiveness of using a Sim-IPE with a home-based patient assessment and intervention for students in undergraduate nursing, nurse practitioner, and physical therapy programs with the goal of enhancing interprofessional team communication and team performance. A mixed-methods, observational research design was used to evaluate teamwork and communication following virtual/web-based deliberate practice and a subsequent face-to-face Sim-IPE with telehealth. There were two distinct stages: (1) provision of interprofessional education elements of teamwork and communication via a virtual web-based platform to interprofessional student teams; (2) participation of all 29 student teams in a Sim-IPE activity using a standardized patient in a simulated home-based setting. Teams scored very high on an interprofessional communication and teamwork scale, and students strongly agreed that the prebriefing, scenario, and debriefing assisted in their learning. Students also valued exposure to telehealth and the ability to work with students from other health professions.

Humans Surviving Cholera Develop Antibodies against Vibrio cholerae O-Specific Polysaccharide That Inhibit Pathogen Motility.

The mechanism of protection against cholera afforded by previous illness or vaccination is currently unknown. We have recently shown that antibodies targeting O-specific polysaccharide (OSP) of Vibrio cholerae correlate highly with protection against cholera. V. cholerae is highly motile and possesses a flagellum sheathed in OSP, and motility of V. cholerae correlates with virulence. Using high-speed video microscopy and building upon previous animal-related work, we demonstrate that sera, polyclonal antibody fractions, and OSP-specific monoclonal antibodies recovered from humans surviving cholera block V. cholerae motility at both subagglutinating and agglutinating concentrations. This antimotility effect is reversed by preadsorbing sera and polyclonal antibody fractions with purified OSP and is associated with OSP-specific but not flagellin-specific monoclonal antibodies. Fab fragments of OSP-specific polyclonal antibodies do not inhibit motility, suggesting a requirement for antibody-mediated cross-linking in motility inhibition. We show that OSP-specific antibodies do not directly affect V. cholerae viability, but that OSP-specific monoclonal antibody highly protects against death in the murine cholera model. We used in vivo competitive index studies to demonstrate that OSP-specific antibodies impede colonization and survival of V. cholerae in intestinal tissues and that this impact is motility dependent. Our findings suggest that the impedance of motility by antibodies targeting V. cholerae OSP contributes to protection against cholera.IMPORTANCE Cholera is a severe dehydrating illness of humans caused by Vibrio choleraeV. cholerae is a highly motile bacterium that has a single flagellum covered in lipopolysaccharide (LPS) displaying O-specific polysaccharide (OSP), and V. cholerae motility correlates with its ability to cause disease. The mechanisms of protection against cholera are not well understood; however, since V. cholerae is a noninvasive intestinal pathogen, it is likely that antibodies that bind the pathogen or its products in the intestinal lumen contribute to protection from infection. Here, we demonstrate that OSP-specific antibodies isolated from humans surviving cholera in Bangladesh inhibit V. cholerae motility and are associated with protection against challenge in a motility-dependent manner.

Immune responses to O-specific polysaccharide (OSP) in North American adults infected with Vibrio cholerae O1 Inaba.

BACKGROUND: Antibodies targeting O-specific polysaccharide (OSP) of Vibrio cholerae may protect against cholera; however, little is known about this immune response in infected immunologically naïve humans. METHODOLOGY: We measured serum anti-OSP antibodies in adult North American volunteers experimentally infected with V. cholerae O1 Inaba El Tor N16961. We also measured vibriocidal and anti-cholera toxin B subunit (CtxB) antibodies and compared responses to those in matched cholera patients in Dhaka, Bangladesh, an area endemic for cholera. PRINCIPAL FINDINGS: We found prominent anti-OSP antibody responses following initial cholera infection: these responses were largely IgM and IgA, and highest to infecting serotype with significant cross-serotype reactivity. The anti-OSP responses peaked 10 days after infection and remained elevated over baseline for ≥ 6 months, correlated with vibriocidal responses, and may have been blunted in blood group O individuals (IgA anti-OSP). We found significant differences in immune responses between naïve and endemic zone cohorts, presumably reflecting previous exposure in the latter. CONCLUSIONS: Our results define immune responses to O-specific polysaccharide in immunologically naive humans with cholera, find that they are largely IgM and IgA, may be blunted in blood group O individuals, and differ in a number of significant ways from responses in previously humans. These differences may explain in part varying degrees of protective efficacy afforded by cholera vaccination between these two populations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT01895855.

Bivalent oral cholera vaccination induces a memory B cell response to the V. cholerae O1-polysaccharide antigen in Haitian adults.

The bivalent killed whole-cell oral cholera vaccine (BivWC) is being increasingly used to prevent cholera. The presence of O-antigen-specific memory B cells (MBC) has been associated with protective immunity against cholera, yet MBC responses have not been evaluated after BivWC vaccination. To address this knowledge gap, we measured V. cholerae O1-antigen MBC responses following BivWC vaccination. Adults in St. Marc, Haiti, received 2 doses of the BivWC vaccine, Shanchol, two weeks apart. Participants were invited to return at days 7, 21, 44, 90, 180 and 360 after the initial vaccination. Serum antibody and MBC responses were assessed at each time-point before and following vaccination. We observed that vaccination with BivWC resulted in significant O-antigen specific MBC responses to both Ogawa and Inaba serotypes that were detected by day 21 and remained significantly elevated over baseline for up to 12 months following vaccination. The BivWC oral cholera vaccine induces durable MBC responses to the V. cholerae O1-antigen. This suggests that long-term protection observed following vaccination with BivWC could be mediated or maintained by MBC responses.

Anti-O-specific polysaccharide (OSP) immune responses following vaccination with oral cholera vaccine CVD 103-HgR correlate with protection against cholera after infection with wild-type Vibrio cholerae O1 El Tor Inaba in North American volunteers.

BACKGROUND: Cholera is an acute voluminous dehydrating diarrheal disease caused by toxigenic strains of Vibrio cholerae O1 and occasionally O139. A growing body of evidence indicates that immune responses targeting the O-specific polysaccharide (OSP) of V. cholerae are involved in mediating protection against cholera. We therefore assessed whether antibody responses against OSP occur after vaccination with live attenuated oral cholera vaccine CVD 103-HgR, and whether such responses correlate with protection against cholera. METHODOLOGY: We assessed adult North American volunteers (n = 46) who were vaccinated with 5 × 108 colony-forming units (CFU) of oral cholera vaccine CVD 103-HgR and then orally challenged with approximately 1 × 105 CFU of wild-type V. cholerae O1 El Tor Inaba strain N16961, either 10 or 90 days post-vaccination. PRINCIPAL FINDINGS: Vaccination was associated with induction of significant serum IgM and IgA anti-OSP and vibriocidal antibody responses within 10 days of vaccination. There was significant correlation between anti-OSP and vibriocidal antibody responses. IgM and IgA anti-OSP responses on day 10 following vaccination were associated with lower post-challenge stool volume (r = -0.44, P = 0.002; r = -0.36, P = 0.01; respectively), and none of 27 vaccinees who developed a ≥1.5 fold increase in any antibody isotype targeting OSP on day 10 following vaccination compared to baseline developed moderate or severe cholera following experimental challenge, while 5 of 19 who did not develop such anti-OSP responses did (P = 0.01). CONCLUSION: Oral vaccination with live attenuated cholera vaccine CVD 103-HgR induces antibodies that target V. cholerae OSP, and these anti-OSP responses correlate with protection against diarrhea following experimental challenge with V. cholerae O1. TRIAL REGISTRATION: ClinicalTrials.gov NCT01895855.

Simulated Interprofessional Education Discharge Planning Meeting to Improve Skills Necessary for Effective Interprofessional Practice.

PURPOSE OF STUDY: The purpose of this study was to evaluate the use of a simulation-enhanced interprofessional education (Sim-IPE) discharge planning learning experience using simulated patients (SPs), to explore the ability for students to communicate with each other and to a patient/caregiver, and to use clinical thinking to make a safe and appropriate interprofessional discharge recommendation. PRIMARY PRACTICE SETTING(S): Educational institution; university simulation center. METHODOLOGY AND SAMPLE: A Sim-IPE was performed with students from physical therapy (N = 46), nursing (N = 25), and social work (N = 11). Students were placed into interprofessional teams. Presimulation, each student was expected to complete a survey and review several items including the patient case, a communication strategy, and community resources. The team then interacted with SPs portraying the patient and the family member. Postsimulation, facilitators led a debriefing session and students completed a post-IPE survey. The Interprofessional Collaborative Competency Attainment Survey (ICCAS) was completed pre- and postexperience. RESULTS: Most students reported that they strongly or somewhat agreed that the experience improved their clinical thinking skills (67%; n = 55), improved awareness of the patient voice in shared decision-making (72.8%; n = 59), improved ability to prioritize patient's list of impairments (75.3%; n = 61), and improved confidence with discharge planning (69.1%; n = 56). IMPLICATIONS FOR CASE MANAGEMENT PRACTICE: Discharge planning is inherently an interprofessional process. Utilizing a simulation as a method to practice discharge planning may have a positive impact on future clinical practice. Completing the ICCAS may not be the appropriate assessment when evaluating change before and after an IPE experience based on the high scores noted preexperience. The use of a simulated discharge planning meeting may improve skills necessary for effective interprofessional practice.

Analysis of the Human Mucosal Response to Cholera Reveals Sustained Activation of Innate Immune Signaling Pathways.

To better understand the innate immune response to Vibrio cholerae infection, we tracked gene expression in the duodenal mucosa of 11 Bangladeshi adults with cholera, using biopsy specimens obtained immediately after rehydration and 30 and 180 days later. We identified differentially expressed genes and performed an analysis to predict differentially regulated pathways and upstream regulators. During acute cholera, there was a broad increase in the expression of genes associated with innate immunity, including activation of the NF-κB, mitogen-activated protein kinase (MAPK), and Toll-like receptor (TLR)-mediated signaling pathways, which, unexpectedly, persisted even 30 days after infection. Focusing on early differences in gene expression, we identified 37 genes that were differentially expressed on days 2 and 30 across the 11 participants. These genes included the endosomal Toll-like receptor gene TLR8, which was expressed in lamina propria cells. Underscoring a potential role for endosomal TLR-mediated signaling in vivo, our pathway analysis found that interferon regulatory factor 7 and beta 1 and alpha 2 interferons were among the top upstream regulators activated during cholera. Among the innate immune effectors, we found that the gene for DUOX2, an NADPH oxidase involved in the maintenance of intestinal homeostasis, was upregulated in intestinal epithelial cells during cholera. Notably, the observed increases in DUOX2 and TLR8 expression were also modeled in vitro when Caco-2 or THP-1 cells, respectively, were stimulated with live V. cholerae but not with heat-killed organisms or cholera toxin alone. These previously unidentified features of the innate immune response to V. cholerae extend our understanding of the mucosal immune signaling pathways and effectors activated in vivo following cholera.

Laboratory evaluation of immunochromatographic rapid diagnostic tests for cholera in Haiti.

BACKGROUND: Rapid diagnostic tests (RDT) for cholera are promising tools for detecting cholera in areas with limited laboratory infrastructure. However, evidence on the characteristics of the many available RDTs is scarce, and their use has been limited by suboptimal performance. We evaluated the performance characteristics of three cholera RDTs from Span Diagnostics, Artron Laboratories, and Standard Diagnostics in a regional laboratory in Haiti. METHODOLOGY/PRINCIPAL FINDINGS: We retrospectively reviewed records from May 2014 to October 2015 of a laboratory-based surveillance program for Vibrio cholerae at Hôpital Saint-Nicolas in Saint-Marc, Haiti. We compared the results of 511 Crystal VC, 129 Artron and 451 SD Bioline RDTs to bacterial culture as the gold standard. Of 905 cultures, 477 (52.7%) were positive for V. cholerae O1, of which 27.7% were serotype Inaba. No cultures grew V. cholerae O139. Sensitivity and specificity of Crystal VC were 98.6% (95%CI: 96.5%-99.6%) and 71.1% (95%CI: 64.7%-76.9%), respectively. Artron demonstrated a sensitivity of 98.6% (95%CI: 92.7%-100%) and specificity of 69.1% (95%CI: 55.2%-80.9%). SD Bioline demonstrated a sensitivity of 81.1% (95%CI: 75.6%-85.8%) and specificity of 92.8% (95%CI: 88.4%-95.9%). Crystal VC and Artron frequently showed false positive O139 bands, whereas none were seen with SD Bioline. CONCLUSIONS/SIGNIFICANCE: There is significant variation in the performance of different cholera diagnostic RDTs. Artron and Crystal VC RDTs have high sensitivity and low specificity, while SD Bioline RDT has low to moderate sensitivity and high specificity when performed by laboratory technicians in Haiti. Study limitations included its retrospective design. The suboptimal characteristics of these tests limit their use as clinical point-of-care tests; however, they may be useful in outbreak response, surveillance, and research in resource-limited settings.

Vibrio cholerae genomic diversity within and between patients.

Cholera is a severe, water-borne diarrhoeal disease caused by toxin-producing strains of the bacterium Vibrio cholerae. Comparative genomics has revealed 'waves' of cholera transmission and evolution, in which clones are successively replaced over decades and centuries. However, the extent of V. cholerae genetic diversity within an epidemic or even within an individual patient is poorly understood. Here, we characterized V. cholerae genomic diversity at a micro-epidemiological level within and between individual patients from Bangladesh and Haiti. To capture within-patient diversity, we isolated multiple (8 to 20) V. cholerae colonies from each of eight patients, sequenced their genomes and identified point mutations and gene gain/loss events. We found limited but detectable diversity at the level of point mutations within hosts (zero to three single nucleotide variants within each patient), and comparatively higher gene content variation within hosts (at least one gain/loss event per patient, and up to 103 events in one patient). Much of the gene content variation appeared to be due to gain and loss of phage and plasmids within the V. cholerae population, with occasional exchanges between V. cholerae and other members of the gut microbiota. We also show that certain intra-host variants have phenotypic consequences. For example, the acquisition of a Bacteroides plasmid and non-synonymous mutations in a sensor histidine kinase gene both reduced biofilm formation, an important trait for environmental survival. Together, our results show that V. cholerae is measurably evolving within patients, with possible implications for disease outcomes and transmission dynamics.

The Live Attenuated Cholera Vaccine CVD 103-HgR Primes Responses to the Toxin-Coregulated Pilus Antigen TcpA in Subjects Challenged with Wild-Type Vibrio cholerae.

One potential advantage of live attenuated bacterial vaccines is the ability to stimulate responses to antigens which are only expressed during the course of infection. To determine whether the live attenuated cholera vaccine CVD 103-HgR (Vaxchora) results in antibody responses to the in vivo-induced toxin-coregulated pilus antigen TcpA, we measured IgA and IgG responses to Vibrio cholerae O1 El Tor TcpA in a subset of participants in a recently reported experimental challenge study. Participants were challenged with V. cholerae O1 El Tor Inaba N16961 either 10 days or 90 days after receiving the vaccine or a placebo. Neither vaccination nor experimental infection with V. cholerae alone resulted in a robust TcpA IgG or IgA response, but each did elicit a strong response to cholera toxin. However, compared to placebo recipients, vaccinees had a marked increase in IgG TcpA antibodies following the 90-day challenge, suggesting that vaccination with CVD 103-HgR resulted in priming for a subsequent response to TcpA. No such difference between vaccine and placebo recipients was observed for volunteers challenged 10 days after vaccination, indicating that this was insufficient time for vaccine-induced priming of the TcpA response. The priming of the response to TcpA and potentially other antigens expressed in vivo by attenuated V. cholerae may have relevance to the maintenance of immunity in areas where cholera is endemic.

Single-Cell Analysis of the Plasmablast Response to Vibrio cholerae Demonstrates Expansion of Cross-Reactive Memory B Cells.

We characterized the acute B cell response in adults with cholera by analyzing the repertoire, specificity, and functional characteristics of 138 monoclonal antibodies (MAbs) generated from single-cell-sorted plasmablasts. We found that the cholera-induced responses were characterized by high levels of somatic hypermutation and large clonal expansions. A majority of the expansions targeted cholera toxin (CT) or lipopolysaccharide (LPS). Using a novel proteomics approach, we were able to identify sialidase as another major antigen targeted by the antibody response to Vibrio cholerae infection. Antitoxin MAbs targeted both the A and B subunits, and most were also potent neutralizers of enterotoxigenic Escherichia coli heat-labile toxin. LPS-specific MAbs uniformly targeted the O-specific polysaccharide, with no detectable responses to either the core or the lipid moiety of LPS. Interestingly, the LPS-specific antibodies varied widely in serotype specificity and functional characteristics. One participant infected with the Ogawa serotype produced highly mutated LPS-specific antibodies that preferentially bound the previously circulating Inaba serotype. This demonstrates durable memory against a polysaccharide antigen presented at the mucosal surface and provides a mechanism for the long-term, partial heterotypic immunity seen following cholera. IMPORTANCE: Cholera is a diarrheal disease that results in significant mortality. While oral cholera vaccines are beneficial, they do not achieve equivalent protection compared to infection with Vibrio cholerae Although antibodies likely mediate protection, the mechanisms of immunity following cholera are poorly understood, and a detailed understanding of antibody responses to cholera is of significance for human health. In this study, we characterized the human response to cholera at the single-plasmablast, monoclonal antibody level. Although this approach has not been widely applied to the study of human bacterial infection, we were able to uncover the basis of cross-reactivity between different V. cholerae serotypes and the likely impact of prior enterotoxigenic Escherichia coli exposure on the response to cholera, as well as identify novel antigenic targets. In addition to improving our understanding of the repertoire and function of the antibody response to cholera in humans, this study has implications for future cholera vaccination efforts.

Antibody Secreting Cell Responses following Vaccination with Bivalent Oral Cholera Vaccine among Haitian Adults.

BACKGROUND: The bivalent whole-cell (BivWC) oral cholera vaccine (Shanchol) is effective in preventing cholera. However, evaluations of immune responses following vaccination with BivWC have been limited. To determine whether BivWC induces significant mucosal immune responses, we measured V. cholerae O1 antigen-specific antibody secreting cell (ASC) responses following vaccination. METHODOLOGY/PRINCIPAL FINDINGS: We enrolled 24 Haitian adults in this study, and administered doses of oral BivWC vaccine 14 days apart (day 0 and day 14). We drew blood at baseline, and 7 days following each vaccine dose (day 7 and 21). Peripheral blood mononuclear cells (PBMCs) were isolated, and ASCs were enumerated using an ELISPOT assay. Significant increases in Ogawa (6.9 cells per million PBMCs) and Inaba (9.5 cells per million PBMCs) OSP-specific IgA ASCs were detected 7 days following the first dose (P < 0.001), but not the second dose. The magnitude of V. cholerae-specific ASC responses did not appear to be associated with recent exposure to cholera. ASC responses measured against the whole lipolysaccharide (LPS) antigen and the OSP moiety of LPS were equivalent, suggesting that all or nearly all of the LPS response targets the OSP moiety. CONCLUSIONS/SIGNIFICANCE: Immunization with the BivWC oral cholera vaccine induced ASC responses among a cohort of healthy adults in Haiti after a single dose. The second dose of vaccine resulted in minimal ASC responses over baseline, suggesting that the current dosing schedule may not be optimal for boosting mucosal immune responses to V. cholerae antigens for adults in a cholera-endemic area.

Immunogenicity of the Bivalent Oral Cholera Vaccine Shanchol in Haitian Adults With HIV Infection.

We evaluated immune responses following bivalent oral cholera vaccination (Shanchol [Shantha Biotechnics]; BivWC) in a cohort of 25 human immunodeficiency virus (HIV)-infected adults in Haiti. Compared with adults without HIV infection, vaccination in HIV-infected individuals resulted in lower vibriocidal responses against Vibrio cholerae O1, and there was a positive relationship between the CD4(+) T-cell count and vibriocidal responses following vaccination. Nevertheless, seroconversion occurred at a rate of 65% against the Ogawa serotype and 74% against the Inaba serotype in adults with HIV infection. These results suggest that the vaccine retains substantial immunogenicity in adults with HIV infection and may benefit this population by protecting against cholera.

Comparative proteomic analysis reveals activation of mucosal innate immune signaling pathways during cholera.

Vibrio cholerae O1 is a major cause of acute watery diarrhea in over 50 countries. Evidence suggests that V. cholerae O1 may activate inflammatory pathways, and a recent study of a Bangladeshi population showed that variants in innate immune genes play a role in mediating susceptibility to cholera. We analyzed human proteins present in the small intestine of patients infected with V. cholerae O1 to characterize the host response to this pathogen. We collected duodenal biopsy specimens from patients with acute cholera after stabilization and again 30 days after initial presentation. Peptides extracted from biopsy specimens were sequenced and quantified using label-free mass spectrometry and SEQUEST. Twenty-seven host proteins were differentially abundant between the acute and convalescent stages of infection; the majority of these have known roles in innate defense, cytokine production, and apoptosis. Immunostaining confirmed that two proteins, WARS and S100A8, were more abundant in lamina propria cells during the acute stage of cholera. Analysis of the differentially abundant proteins revealed the activation of key regulators of inflammation by the innate immune system, including Toll-like receptor 4, nuclear factor kappa-light-chain-enhancer of activated B cells, mitogen-activated protein kinases, and caspase-dependent inflammasomes. Interleukin-12ß (IL-12ß) was a regulator of several proteins that were activated during cholera, and we confirmed that IL-12ß was produced by lymphocytes recovered from duodenal biopsy specimens of cholera patients. Our study shows that a broad inflammatory response is generated in the gut early after onset of cholera, which may be critical in the development of long-term mucosal immunity against V. cholerae O1.

Evaluation of matrix-assisted laser desorption ionization-time of flight mass spectrometry for identification of Vibrio cholerae.

We evaluated the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MS) for the identification of Vibrio cholerae. MS identified all 42 isolates of V. cholerae O1 and O139 and 7 of 9 non-O1/O139 isolates. MS correctly discriminated between all Aeromonas and V. cholerae isolates. Overall, MS performed as well as or better than biochemical methods.