A5084859141- Vibrio bacteria research studies
- Escherichia coli research studies
- Salmonella and Campylobacter epidemiology
- Child Nutrition and Water Access
- Viral gastroenteritis research and epidemiology
- Influenza Virus Research Studies
- SARS-CoV-2 and COVID-19 Research
- Monoclonal and Polyclonal Antibodies Research
- Immunotherapy and Immune Responses
- Aquaculture disease management and microbiota
- vaccines and immunoinformatics approaches
- Antibiotic Resistance in Bacteria
- COVID-19 epidemiological studies
- SARS-CoV-2 detection and testing
- COVID-19 Clinical Research Studies
- Gut microbiota and health
- Immune Response and Inflammation
- Bacteriophages and microbial interactions
- Immune Cell Function and Interaction
- Pneumonia and Respiratory Infections
- Fecal contamination and water quality
- Vaccine Coverage and Hesitancy
- Cancer Immunotherapy and Biomarkers
- Clostridium difficile and Clostridium perfringens research
- Mosquito-borne diseases and control
Harvard University
2016-2025
Massachusetts General Hospital
2016-2025
Personalis (United States)
2022-2025
Boston Children's Hospital
2018-2024
Center for Global Health
2021-2024
MaineGeneral Medical Center
2019-2023
Harvard Global Health Institute
2023
Brigham and Women's Hospital
2023
Federal Ministry of Health
2021-2022
University of California, Davis
2022
Although cholera has been present in Latin America since 1991, it had not epidemic Haiti for at least 100 years. Recently, however, there a severe outbreak of Haiti.We used third-generation single-molecule real-time DNA sequencing to determine the genome sequences 2 clinical Vibrio cholerae isolates from current Haiti, 1 strain that caused and strains isolated South Asia 2002 2008. Using primary sequence data, we compared genomes these 5 set previously obtained partial genomic 23 diverse V....
We measured plasma and/or serum antibody responses to the receptor-binding domain (RBD) of spike (S) protein SARS-CoV-2 in 343 North American patients infected with (of which 93% required hospitalization) up 122 days after symptom onset and compared them 1548 individuals whose blood samples were obtained prior pandemic. After setting seropositivity thresholds for perfect specificity (100%), we estimated sensitivities 95% IgG, 90% IgA, 81% IgM detecting between 15 28 onset. While median time...
Phylogenetics of superspreading One important characteristic coronavirus epidemiology is the occurrence events. These are marked by a disproportionate number cases originating from often-times asymptomatic individuals. Using rich sequence dataset early stages Boston outbreak, Lemieux et al. identified events in specific settings and analyzed them phylogenetically (see Perspective Alizon). ancestral trait inference, authors several importation events, further investigated context contribution...
Characterizing the humoral immune response to SARS-CoV-2 and developing accurate serologic assays are needed for diagnostic purposes estimating population-level seroprevalence. We measured kinetics of early antibody responses receptor-binding domain (RBD) spike (S) protein in a cohort 259 symptomatic North American patients infected with (up 75 days after symptom onset) compared levels 1548 individuals whose blood samples were obtained prior pandemic. Between 14-28 from onset symptoms, IgG,...
The diagnosis of COVID-19 requires integration clinical and laboratory data. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic assays play a central role in have fixed technical performance metrics. Interpretation becomes challenging because the sensitivity changes as virus clears immune response emerges. Our goal was to examine two most common SARS-CoV-2 test modalities, polymerase chain reaction (PCR) serology, over disease course provide insight into their...
BackgroundDespite recent progress in understanding the molecular basis of Vibrio cholerae pathogenesis, there is relatively little knowledge factors that determine variability human susceptibility to V. infection.Methods and FindingsWe performed an observational study a cohort household contacts cholera patients Bangladesh, compared baseline characteristics members who went on develop culture-positive infection with individuals did not infection. Although vibriocidal antibody only previously...
ABSTRACT Individuals with blood group O are more susceptible than other individuals to severe cholera, although the mechanism underlying this association is unknown. To assess respective roles of both intrinsic host factors and adaptive immune responses that might influence susceptibility infection Vibrio cholerae , we prospectively followed a cohort household contacts patients cholera in Bangladesh. In study, made novel observation persons were less likely those groups become infected V. O1...
We examined demographic, microbiologic, and clinical data from patients presenting during 1988, 1998, 2004 flood-associated diarrheal epidemics at a diarrhea treatment hospital in Dhaka, Bangladesh. Compared with non-flood periods, individuals were older, more severely dehydrated, of lower socioeconomic status. During epidemics, Vibrio cholerae was the most commonly identified cause diarrhea, only pathogen whose incidence proportionally increased each epidemic compared seasonally matched...
Disability after childhood diarrhea is an important burden on global productivity. Recent studies suggest that gut bacterial communities influence how humans recover from infectious diarrhea, but we still lack extensive data and mechanistic hypotheses for these respond to diarrheal disease its treatment. Here, report Vibrio cholerae infection, the human microbiota undergoes orderly reproducible succession features transient reversals in relative levels of enteric Bacteroides Prevotella....
Multiple Vibrio cholerae infections in the same household are common. The objective of this study was to examine incidence V. infection and associated clinical symptoms contacts patients with cholera identify risk factors for development severe dehydration cohort.Household hospitalized were observed frequent assessments collection serum rectal swab samples culture a period 21 days after presentation index case.One-half (460 944) all reported diarrhea during period, most frequently began 2...
The impact of phage predation on bacterial pathogens in the context human disease is not currently appreciated. Here, we show that predatory interactions a with an important environmentally transmitted pathogen, Vibrio cholerae, can modulate evolutionary trajectory this pathogen during natural course infection within individual patients. We analyzed geographically and temporally disparate cholera patient stool samples from Haiti Bangladesh found drive genomic diversity intra-patient V....
BackgroundBetween April and June, 2012, a reactive cholera vaccination campaign was done in Haiti with an oral inactivated bivalent whole-cell vaccine. We aimed to assess the effectiveness of vaccine case-control study likelihood bias that bias-indicator study.MethodsResidents Bocozel or Grand Saline who were eligible for (ie, age ≥12 months, not pregnant, living region at time campaign) included. In primary study, cases had acute watery diarrhoea, sought treatment one three participating...
Klebsiella pneumoniae is a leading cause of infection-related deaths globally, yet little known about human antibody responses to invasive K pneumoniae. We sought determine whether the O-specific polysaccharide antigen immunogenic in humans with bloodstream infection. also define cross-reactivity among structurally related subtypes and assess effect capsule production on polysaccharide-targeted binding function. In this prospective cohort study, we compared plasma consecutively enrolled...
In Brazil, where Leishmania chagasi causes endemic American visceral leishmaniasis (AVL), the spread and maintenance of human disease are attributed to canine reservoirs. However, despite measures directed toward elimination infected canines, incidence continues increase. To evaluate role canines in acquisition AVL by humans, we undertook a controlled intervention study three similar, but isolated, valleys Pancas, Espírito Santo, Brazil. two experimental (intervention) valleys, dogs were...
Bangladesh experienced severe flooding and diarrheal epidemics in 2007. We compared flood data from 2007 with 2004 1998 for patients attending the ICDDR,B hospital Dhaka. In 2007, Vibrio cholerae O1 (33%), rotavirus (12%), enterotoxigenic Escherichia coli (ETEC) (12%) were most prevalent. More dehydration was seen (P < 0.001). V. Inaba (52%) Ogawa (48%) seen, whereas it primarily types, respectively 51% of ETEC produced heat labile toxin (LT) 0.001 2004), 22% expressed stable (ST) 0.001),...
Cholera, caused by Vibrio cholerae, is a noninvasive dehydrating enteric disease with high mortality rate if untreated. Infection V. cholerae elicits long-term protection against subsequent in countries where the endemic. Although mechanism of this protective immunity unknown, it has been hypothesized that mucosal response to infection may be mediated anamnestic responses memory B cells gut-associated lymphoid tissue. To characterize B-cell cholera, we enrolled cohort 39 hospitalized...
Background Mucosal Associated Invariant T (MAIT) cells are innate-like found in abundance the intestinal mucosa, and thought to play a role bridging innate-adaptive interface. Methods We measured MAIT cell frequencies antibody responses blood from patients presenting with culture-confirmed severe cholera hospital Dhaka, Bangladesh at days 2, 7, 30, 90 of illness. Results that (CD3+CD4−CD161hiVα7.2+) were maximally activated day 7 after onset cholera. In adult patients, did not change over...
Natural selection in a Bangladeshi population from the cholera-endemic Ganges River Delta has targeted genes associated with cholera resistance and an innate immunity pathway activated by Vibrio cholerae .
ABSTRACT The mediators of protective immunity against cholera are currently unknown, but memory B-cell responses may play a central role in facilitating long-term and anamnestic Vibrio cholerae , the cause cholera. We compared adults with natural Bangladesh ( n = 70) to Bangladeshi after one-dose 30) or two-dose administration an oral killed vaccine, WC-rBS (Dukoral; Crucell), assessing at acute stage disease prevaccination then on days 3, 30, 90, 180, 270, 360. Individuals developed...
ABSTRACT Vibrio cholerae O1 causes cholera, a dehydrating diarrheal disease. We have previously shown that V. -specific memory B cell responses develop after cholera infection, and we hypothesize these mediate long-term protective immunity against cholera. prospectively followed household contacts of patients to determine whether the presence circulating antigen-specific cells on enrollment was associated with protection infection over 30-day period. Two hundred thirty-six 122 index were...
ABSTRACT Immunity against Vibrio cholerae O1 is serogroup specific, and serogrouping defined by the O-specific polysaccharide (OSP) part of lipopolysaccharide (LPS). Despite this, human immune responses to V. OSP have not previously been characterized. We assessed in adults with cholera caused El Tor serotype Inaba or Ogawa Dhaka, Bangladesh, using OSP-core–bovine serum albumin (OSPc:BSA) conjugates; targeted these conjugates. Responses Inaba-infected patients LPS increased significantly...
We characterized the acute B cell response in adults with cholera by analyzing repertoire, specificity, and functional characteristics of 138 monoclonal antibodies (MAbs) generated from single-cell-sorted plasmablasts. found that cholera-induced responses were high levels somatic hypermutation large clonal expansions. A majority expansions targeted toxin (CT) or lipopolysaccharide (LPS). Using a novel proteomics approach, we able to identify sialidase as another major antigen antibody Vibrio...