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1.
Microbiol Resour Announc ; : e0013524, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656213

RESUMO

We report 18 coding-complete genome sequences of emerging SARS-CoV-2 Omicron sub-lineages JN.1, JN.1.4, and JN.1.11 from Bangladesh. Nasopharyngeal swab samples were obtained from individuals with COVID-19 symptoms between December 2023 and January 2024. Whole genome sequencing was performed following the ARTIC Network-based protocol using Oxford Nanopore Technology.

2.
Microbiol Resour Announc ; 12(10): e0056223, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37668364

RESUMO

We announce the coding-complete genomes of four different strains of SARS-CoV-2 Omicron lineages, XBB.1.16, XBB.2.3, FL.4 (alias of XBB.1.9.1.4), and XBB.3. These strains were obtained between October 2022 and May 2023 from nasopharyngeal swabs of four Bangladeshi individuals, while one of them had a travel history. Genomic data were produced by implementing ARTIC Network-based amplicon sequencing using the Oxford Nanopore Technology.

3.
Am J Trop Med Hyg ; 109(3): 575-583, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37580033

RESUMO

Despite focusing on cholera burden, epidemiologic studies in Bangladesh tend to be limited in geographic scope. National-level cholera surveillance data can help inform cholera control strategies and assess the effectiveness of preventive measures. Hospital-based sentinel surveillance among patients with suspected diarrhea in different sites across Bangladesh has been conducted since 2014. We selected an age-stratified sample of 20 suspected cholera cases each week from each sentinel site, tested stool for the presence of Vibrio cholerae O1/O139 by culture, and characterized antibiotic susceptibility in a subset of culture-positive isolates. We estimated the odds of being culture positive among suspected cholera cases according to different potential risk factors. From May 4, 2014 through November 30, 2021, we enrolled 51,414 suspected cases from our sentinel surveillance sites. We confirmed V. cholerae O1 in 5.2% of suspected cases through microbiological culture. The highest proportion of confirmed cholera cases was from Chittagong (9.7%) and the lowest was from Rangpur Division (0.9%). Age, number of purges, duration of diarrhea, occupation, and season were the most relevant factors in distinguishing cholera-positive suspected cases from cholera-negative suspected cases. Nationwide surveillance data show that cholera is circulating in Bangladesh and the southern region is more affected than the northern region. Antimicrobial resistance patterns indicate that multidrug resistance (resistance to three or more classes of antibiotics) of V. cholerae O1 could be a major threat in the future. Alignment of these results with Bangladesh's cholera-control program will be the foundation for future research into the efficacy of cholera-control initiatives.


Assuntos
Cólera , Vibrio cholerae O1 , Humanos , Lactente , Cólera/epidemiologia , Cólera/microbiologia , Vigilância de Evento Sentinela , Bangladesh/epidemiologia , Surtos de Doenças , Diarreia/epidemiologia , Diarreia/microbiologia
4.
Front Genet ; 14: 1220906, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621704

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved to give rise to a highly transmissive and immune-escaping variant of concern, known as Omicron. Many aspects of the evolution of SARS-CoV-2 and the driving forces behind the ongoing Omicron outbreaks remain unclear. Substitution at the receptor-binding domain (RBD) in the spike protein is one of the primary strategies of SARS-CoV-2 Omicron to hinder recognition by the host angiotensin-converting enzyme 2 (ACE2) receptor and avoid antibody-dependent defense activation. Here, we scanned for adaptive evolution within the SARS-CoV-2 Omicron genomes reported from Bangladesh in the public database GISAID (www.gisaid.org; dated 2 April 2023). The ratio of the non-synonymous (Ka) to synonymous (Ks) nucleotide substitution rate, denoted as ω, is an indicator of the selection pressure acting on protein-coding genes. A higher proportion of non-synonymous to synonymous substitutions (Ka/Ks or ω > 1) indicates positive selection, while Ka/Ks or ω near zero indicates purifying selection. An equal amount of non-synonymous and synonymous substitutions (Ka/Ks or ω = 1) refers to neutrally evolving sites. We found evidence of adaptive evolution within the spike (S) gene of SARS-CoV-2 Omicron isolated from Bangladesh. In total, 22 codon sites of the S gene displayed a signature of positive selection. The data also highlighted that the receptor-binding motif within the RBD of the spike glycoprotein is a hotspot of adaptive evolution, where many of the codons had ω > 1. Some of these adaptive sites at the RBD of the spike protein are known to be associated with increased viral fitness. The M gene and ORF6 have also experienced positive selection. These results suggest that although purifying selection is the dominant evolutionary force, positive Darwinian selection also plays a vital role in shaping the evolution of SARS-CoV-2 Omicron in Bangladesh.

5.
Medicina (Kaunas) ; 59(7)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37512091

RESUMO

Background and Objectives: The morbidity and mortality associated with COVID-19 have burdened worldwide healthcare systems beyond their capacities, forcing them to promptly investigate the virus characteristics and its associated outcomes. This clinical analysis aimed to explore the key factors related to the fatal outcome of severe COVID-19 cases. Materials and Methods: Thirty-five adult severe COVID-19 patients were enrolled from two COVID-19 hospitals in Dhaka, Bangladesh. Clinical manifestation, comorbid conditions, medications, SARS-CoV-2 RT-PCR related cycle threshold (CT) value, hematology, biochemical parameters with SARS-CoV-2 specific IgG and IgM responses at enrollment were compared between the survivors and deceased participants. Results: Total 27 patients survived and 8 patients died within 3 months of disease onset. Deceased patients suffered longer from shortness of breath than the survived (p = 0.049). Among the severe cases, 62% of the deceased patients had multiple comorbid condition compared to 48% of those who survived. Interestingly, the anti-viral was initiated earlier among the deceased patients [median day of 1 (IQR: 0, 1.5) versus 6.5 (IQR: 6.25, 6.75)]. Most of the survivors (55%) received a combination of anticoagulant (p = 0.034). Liver enzymes, creatinine kinase, and procalcitonin were higher among the deceased patients during enrollment. The median CT value among the deceased was significantly lower than the survivors (p = 0.025). A significant difference for initial IgG (p = 0.013) and IgM (p = 0.030) responses was found between the survivor and the deceased groups. Conclusions: The factors including older age, male gender, early onset of respiratory distress, multiple comorbidities, low CT value, and poor antibody response may contribute to the fatal outcome in severe COVID-19 patients. Early initiation of anti-viral and a combination of anticoagulant treatment may prevent or lower the fatality among severe COVID-19 cases.


Assuntos
COVID-19 , Adulto , Humanos , Masculino , SARS-CoV-2 , Estudos Prospectivos , Bangladesh/epidemiologia , Antivirais , Anticoagulantes , Imunoglobulina G , Imunoglobulina M
6.
Nat Commun ; 14(1): 3773, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355673

RESUMO

Ongoing diarrheal disease surveillance throughout Bangladesh over the last decade has revealed seasonal localised cholera outbreaks in Cox's Bazar, where both Bangladeshi Nationals and Forcibly Displaced Myanmar Nationals (FDMNs) reside in densely populated settlements. FDMNs were recently targeted for the largest cholera vaccination campaign in decades. We aimed to infer the epidemic risk of circulating Vibrio cholerae strains by determining if isolates linked to the ongoing global cholera pandemic ("7PET" lineage) were responsible for outbreaks in Cox's Bazar. We found two sublineages of 7PET in this setting during the study period; one with global distribution, and a second lineage restricted to Asia and the Middle East. These subclades were associated with different disease patterns that could be partially explained by genomic differences. Here we show that as the pandemic V. cholerae lineage circulates in this vulnerable population, without a vaccine intervention, the risk of an epidemic was very high.


Assuntos
Cólera , Vibrio cholerae , Humanos , Vibrio cholerae/genética , Cólera/epidemiologia , Cólera/prevenção & controle , Bangladesh/epidemiologia , Genômica , Programas de Imunização , Pandemias
7.
Front Public Health ; 11: 1132927, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124777

RESUMO

Background: Enterotoxigenic Escherichia coli (ETEC) and Vibrio cholerae O1 are most common bacterial causes of diarrheal diseases in Bangladesh. This analysis projected distribution of ETEC and V. cholerae O1 among diarrheal patients of icddr,b, Dhaka hospital in two diarrheal peaks of 2022. Methodology: Under the 2% systematic surveillance system, stool samples collected from diarrheal patients of icddr,b hospital were cultured and diagnostic testing was done for ETEC and V. cholerae O1. Comparison of positive cases was done between first peak (March-April) and second peak (October-November) in 2022. Results: A total of 2,937 stool specimens were tested of which 12% were ETEC and 20% were V. cholerae O1. About 40% of the severe dehydration cases were infected with V. cholerae O1. Predominant ETEC enterotoxin type was 'LT/ST' (41%). The LT enterotoxin significantly increased from 13% to 28% in the second peak (p = 0.015). The predominant colonization factors (CFs) on ETEC were CS5 + CS6 (23%), followed by CS6 (15%). CF-positive isolates was significantly higher in the second peak (36%) than in the first peak (22%) (p = 0.043). Total 14% cases were co-infected with ETEC and V. cholerae O1. Significant differences in the distribution of enterotoxin types were observed (p = 0.029) among the co-infection cases. Conclusion: Changing patterns of enterotoxin and CFs observed in ETEC pathogens should be taken into consideration for ETEC vaccine development. Considering cholera and ETEC biannual trends in causing diarrheal epidemics and outbreaks, emphasizes the need for thoughts on combination vaccine strategies for preventing acute watery diarrhea due to the two major bacterial pathogens.


Assuntos
Escherichia coli Enterotoxigênica , Epidemias , Infecções por Escherichia coli , Vibrio cholerae O1 , Humanos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Bangladesh/epidemiologia , Diarreia/epidemiologia , Enterotoxinas
8.
Microbiol Resour Announc ; 12(3): e0000123, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36779717

RESUMO

Here, we report the coding-complete genome sequences of 40 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains of the newly emerged recombinant Omicron variants XBB, XBB.1, and XBB.2. The strains were isolated from nasopharyngeal swab samples that had been collected from symptomatic patients in Bangladesh between September and October 2022 and were sequenced using an Oxford Nanopore Technologies (ONT) system.

9.
Microbiol Resour Announc ; 12(1): e0095022, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36472422

RESUMO

We announce the coding-complete genome sequences of 23 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron strains obtained from Bangladeshi individuals. The Oxford Nanopore Technologies sequencing platform was utilized to generate the genomic data, deploying ARTIC Network-based amplicon sequencing.

10.
Vaccines (Basel) ; 10(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36560479

RESUMO

BACKGROUND: From May to December 2021, Bangladesh experienced a major surge in the Delta variant of SARS-CoV-2. The earlier rollout of several vaccines offered the opportunity to evaluate vaccine effectiveness against this variant. METHODS: A prospective, test-negative case-control study was conducted in five large hospitals in Dhaka between September and December 2021. The subjects were patients of at least 18 years of age who presented themselves for care, suffering COVID-like symptoms of less than 10 days' duration. The cases had PCR-confirmed infections with SARS-CoV-2, and up to 4 PCR test-negative controls were matched to each case, according to hospital, date of presentation, and age. Vaccine protection was assessed as being the association between the receipt of a complete course of vaccine and the occurrence of SARS-CoV-2 disease, with symptoms beginning at least 14 days after the final vaccine dose. RESULTS: In total, 313 cases were matched to 1196 controls. The genotyping of case isolates revealed 99.6% to be the Delta variant. Receipt of any vaccine was associated with 12% (95% CI: -21 to 37, p = 0.423) protection against all episodes of SARS-CoV-2. Among the three vaccines for which protection was evaluable (Moderna (mRNA-1273); Sinopharm (Vero Cell-Inactivated); Serum Institute of India (ChAdOx1 nCoV-19)), only the Moderna vaccine was associated with significant protection (64%; 95% CI: 10 to 86, p = 0.029). Protection by the receipt of any vaccine against severe disease was 85% (95% CI: 27 to 97, p = 0.019), with protection estimates of 75% to 100% for the three vaccines. CONCLUSIONS: Vaccine protection against COVID-19 disease of any severity caused by the Delta variant was modest in magnitude and significant for only one of the three evaluable vaccines. In contrast, protection against severe disease was high in magnitude and consistent for all three vaccines. Because our findings are not in complete accord with evaluations of the same vaccines in more affluent settings, our study underscores the need for country-level COVID-19 vaccine evaluations in developing countries.

11.
Am J Trop Med Hyg ; 107(4): 845-849, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-35970285

RESUMO

Early detection of SARS-CoV-2 infection is crucial to prevent its spread. This study aimed to document test sensitivity/specificity, correlation with cycle threshold value from polymerase chain reaction (PCR), fitness-for-use in different populations and settings, and user perspectives that could inform large-scale implementation. In this study, we evaluated the performance of a rapid antigen detection test, BD Veritor, and compared this (and another rapid test, Standard Q) against reverse transcription PCR (RT-PCR) in terms of sensitivity and specificity in 130 symptomatic and 130 asymptomatic adults. In addition, we evaluated the suitability and ease of use of the BD Veritor test in a subsample of study participants (n = 42) and implementers (n = 5). At 95% confidence interval, the sensitivity of the BD Veritor and Standard Q test were 70% and 63% in symptomatic and 87% and 73% in asymptomatic individuals, respectively, regarding positive SARS-CoV-2 RT-PCR results. Overall, the BD Veritor test was 78% sensitive and 99.5% specific compared with RT-PCR irrespective of the cycle threshold. This warrants large field evaluation as well as use of the rapid antigen test for quick assessment of SARS-CoV-2 for containment of epidemics in the country.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Antígenos Virais , Bangladesh/epidemiologia , COVID-19/diagnóstico , Teste para COVID-19 , Humanos , Sensibilidade e Especificidade
12.
Microbiol Resour Announc ; 11(4): e0011922, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35323016

RESUMO

We report the coding-complete genome sequences of 25 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sublineage B.1.1.529 Omicron strains obtained from Bangladeshi individuals in samples collected between December 2021 and January 2022. Genomic data were generated by Nanopore sequencing using the amplicon sequencing approach developed by the ARTIC Network.

13.
PLoS Negl Trop Dis ; 16(1): e0010102, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34982773

RESUMO

BACKGROUND: COVID-19 caused by SARS-CoV-2 ranges from asymptomatic to severe disease and can cause fatal and devastating outcome in many cases. In this study, we have compared the clinical, biochemical and immunological parameters across the different disease spectrum of COVID-19 in Bangladeshi patients. METHODOLOGY/PRINCIPAL FINDINGS: This longitudinal study was conducted in two COVID-19 hospitals and also around the community in Dhaka city in Bangladesh between November 2020 to March 2021. A total of 100 patients with COVID-19 infection were enrolled and classified into asymptomatic, mild, moderate and severe cases (n = 25/group). In addition, thirty age and sex matched healthy participants were enrolled and 21 were analyzed as controls based on exclusion criteria. After enrollment (study day1), follow-up visits were conducted on day 7, 14 and 28 for the cases. Older age, male gender and co-morbid conditions were the risk factors for severe COVID-19 disease. Those with moderate and severe cases of infection had low lymphocyte counts, high neutrophil counts along with a higher neutrophil-lymphocyte ratio (NLR) at enrollment; this decreased to normal range within 42 days after the onset of symptom. At enrollment, D-dimer, CRP and ferritin levels were elevated among moderate and severe cases. The mild, moderate, and severe cases were seropositive for IgG antibody by day 14 after enrollment. Moderate and severe cases showed significantly higher IgM and IgG levels of antibodies to SARS-CoV-2 compared to mild and asymptomatic cases. CONCLUSION/SIGNIFICANCE: We report on the clinical, biochemical, and hematological parameters associated with the different severity of COVID-19 infection. We also show different profile of antibody response against SARS-CoV-2 in relation to disease severity, especially in those with moderate and severe disease manifestations compared to the mild and asymptomatic infection.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/diagnóstico , COVID-19/imunologia , Índice de Gravidade de Doença , Adulto , Formação de Anticorpos , Bangladesh , Teste para COVID-19 , Estudos de Coortes , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio , Humanos , Imunoglobulina G , Estudos Longitudinais , Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Fatores de Risco , SARS-CoV-2 , Carga Viral
14.
Nat Microbiol ; 6(10): 1271-1278, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34497354

RESUMO

Genomics, combined with population mobility data, used to map importation and spatial spread of SARS-CoV-2 in high-income countries has enabled the implementation of local control measures. Here, to track the spread of SARS-CoV-2 lineages in Bangladesh at the national level, we analysed outbreak trajectory and variant emergence using genomics, Facebook 'Data for Good' and data from three mobile phone operators. We sequenced the complete genomes of 67 SARS-CoV-2 samples (collected by the IEDCR in Bangladesh between March and July 2020) and combined these data with 324 publicly available Global Initiative on Sharing All Influenza Data (GISAID) SARS-CoV-2 genomes from Bangladesh at that time. We found that most (85%) of the sequenced isolates were Pango lineage B.1.1.25 (58%), B.1.1 (19%) or B.1.36 (8%) in early-mid 2020. Bayesian time-scaled phylogenetic analysis predicted that SARS-CoV-2 first emerged during mid-February in Bangladesh, from abroad, with the first case of coronavirus disease 2019 (COVID-19) reported on 8 March 2020. At the end of March 2020, three discrete lineages expanded and spread clonally across Bangladesh. The shifting pattern of viral diversity in Bangladesh, combined with the mobility data, revealed that the mass migration of people from cities to rural areas at the end of March, followed by frequent travel between Dhaka (the capital of Bangladesh) and the rest of the country, disseminated three dominant viral lineages. Further analysis of an additional 85 genomes (November 2020 to April 2021) found that importation of variant of concern Beta (B.1.351) had occurred and that Beta had become dominant in Dhaka. Our interpretation that population mobility out of Dhaka, and travel from urban hotspots to rural areas, disseminated lineages in Bangladesh in the first wave continues to inform government policies to control national case numbers by limiting within-country travel.


Assuntos
COVID-19/transmissão , Telefone Celular/estatística & dados numéricos , Genoma Viral/genética , SARS-CoV-2/genética , Mídias Sociais/estatística & dados numéricos , Bangladesh/epidemiologia , Teorema de Bayes , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Genômica , Política de Saúde/legislação & jurisprudência , Humanos , Filogenia , Dinâmica Populacional/estatística & dados numéricos , SARS-CoV-2/classificação , Viagem/legislação & jurisprudência , Viagem/estatística & dados numéricos
15.
Microbiol Resour Announc ; 10(28): e0056021, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264100

RESUMO

We report the coding-complete genome sequences of 15 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sublineage B.1.617.2 strains that were obtained from Bangladeshi individuals with a history of recent travel to India and from the Bangladeshi community. Genomic data were generated by Nanopore sequencing using the amplicon sequencing approach developed by the ARTIC Network.

16.
Ann Glob Health ; 86(1): 29, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32211299

RESUMO

Background: Hepatitis A virus (HAV) and hepatitis E virus (HEV) are transmitted by the fecal-oral route and are responsible for epidemic and sporadic outbreaks of acute hepatitis in low-income countries like Bangladesh. Objective: The purpose of this study was to describe the seroprevalence of acute hepatitis due to HAV and HEV infection in Bangladesh. Methods: The nationwide food-borne illness surveillance started in 2014 at 10 different hospitals which covered seven divisions of Bangladesh. Blood samples were collected from suspected acute hepatitis cases and screened for the anti-HAV IgM and anti-HEV IgM using enzyme-linked immunosorbent assay (ELISA). Participants' socioeconomic status, clinical, sanitation and food history were recorded. Multivariate logistic regression was performed to determine the risk factors associated with HAV and HEV infection. Findings: A total of 998 patients were enrolled and tested for both HAV and HEV. Among these, 19% (191/998) were identified as HAV positive and 10% (103/998) were HEV positive. The median age was 12 years and 25 years for HAV and HEV positive patients, respectively. The prevalence of HAV was higher among the females (24.9%), whereas HEV was higher among males (11.2%). The highest occurrence of HAV was observed among children while HEV was most prevalent in the 15-60 years age group (12.4%). Conclusion: Through our nationwide surveillance, it is evident that hepatitis A and hepatitis E infection is common in Bangladesh. These data will be useful towards planning preventive and control measures by strengthening the sanitation programs and vaccination strategies in Bangladesh.


Assuntos
Hepatite A/epidemiologia , Hepatite E/epidemiologia , Doença Aguda , Adolescente , Adulto , Distribuição por Idade , Bangladesh/epidemiologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite A/imunologia , Anticorpos Anti-Hepatite A/imunologia , Anticorpos Anti-Hepatite/imunologia , Hepatite E/imunologia , Humanos , Imunoglobulina M/imunologia , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Estudos Soroepidemiológicos , Distribuição por Sexo , Adulto Jovem
17.
Clin Infect Dis ; 71(7): 1635-1642, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31891368

RESUMO

BACKGROUND: Despite advances in prevention, detection, and treatment, cholera remains a major public health problem in Bangladesh and little is known about cholera outside of limited historical sentinel surveillance sites. In Bangladesh, a comprehensive national cholera control plan is essential, although national data are needed to better understand the magnitude and geographic distribution of cholera. METHODS: We conducted systematic hospital-based cholera surveillance among diarrhea patients in 22 sites throughout Bangladesh from 2014 to 2018. Stool specimens were collected and tested for Vibrio cholerae by microbiological culture. Participants' socioeconomic status and clinical, sanitation, and food history were recorded. We used generalized estimating equations to identify the factors associated with cholera among diarrhea patients. RESULTS: Among 26 221 diarrhea patients enrolled, 6.2% (n = 1604) cases were V. cholerae O1. The proportion of diarrhea patients positive for cholera in children <5 years was 2.1% and in patients ≥5 years was 9.5%. The proportion of cholera in Dhaka and Chittagong Division was consistently high. We observed biannual seasonal peaks (pre- and postmonsoon) for cholera across the country, with higher cholera positivity during the postmonsoon in western regions and during the pre-monsoon season in eastern regions. Cholera risk increased with age, occupation, and recent history of diarrhea among household members. CONCLUSIONS: Cholera occurs throughout a large part of Bangladesh. Cholera-prone areas should be prioritized to control the disease by implementation of targeted interventions. These findings can help strengthen the cholera-control program and serve as the basis for future studies for tracking the impact of cholera-control interventions in Bangladesh.


Assuntos
Cólera , Vibrio cholerae , Bangladesh/epidemiologia , Criança , Cólera/epidemiologia , Diarreia/epidemiologia , Hospitais , Humanos
18.
Sci Rep ; 9(1): 5865, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971707

RESUMO

Toxigenic Vibrio cholerae of the O139 serogroup have been responsible for several large cholera epidemics in South Asia, and continue to be of clinical and historical significance today. This serogroup was initially feared to represent a new, emerging V. cholerae clone that would lead to an eighth cholera pandemic. However, these concerns were ultimately unfounded. The majority of clinically relevant V. cholerae O139 isolates are closely related to serogroup O1, biotype El Tor V. cholerae, and comprise a single sublineage of the seventh pandemic El Tor lineage. Although related, these V. cholerae serogroups differ in several fundamental ways, in terms of their O-antigen, capsulation phenotype, and the genomic islands found on their chromosomes. Here, we present four complete, high-quality genomes for V. cholerae O139, obtained using long-read sequencing. Three of these sequences are from toxigenic V. cholerae, and one is from a bacterium which, although classified serologically as V. cholerae O139, lacks the CTXφ bacteriophage and the ability to produce cholera toxin. We highlight fundamental genomic differences between these isolates, the V. cholerae O1 reference strain N16961, and the prototypical O139 strain MO10. These sequences are an important resource for the scientific community, and will improve greatly our ability to perform genomic analyses of non-O1 V. cholerae in the future. These genomes also offer new insights into the biology of a V. cholerae serogroup that, from a genomic perspective, is poorly understood.


Assuntos
Genoma Bacteriano , Vibrio cholerae O139/genética , Bacteriófagos/fisiologia , Toxina da Cólera/metabolismo , Farmacorresistência Bacteriana/genética , Variação Genética , Antígenos O/genética , Filogenia , Sorogrupo , Vibrio cholerae O139/classificação , Vibrio cholerae O139/patogenicidade , Vibrio cholerae O139/virologia
19.
PLoS Negl Trop Dis ; 13(1): e0007124, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30703097

RESUMO

BACKGROUND: Cholera remains a substantial health burden in Asia and Africa particularly in resource poor settings. The standard procedures to identify the etiological organism V. cholerae are isolation from microbiological culture from stool as well as Polymerase Chain Reaction (PCR). Both the processes are highly lab oriented, labor extensive, time consuming, and expensive. In an effort to control for outbreaks and epidemics; an effective, convenient, quick and relatively less expensive detection method is imperative, without compromising the sensitivity and specificity that exists at present. The objective of this component of the study was to evaluate the effectiveness of a locally produced rapid diagnostic test (RDT) for cholera diagnosis. METHODS: In Bangladesh, nationwide cholera surveillance is ongoing in 22 hospitals covering all 8 divisions of the country since June, 2016. In the surveillance, stool samples have been collected from patients presenting to hospitals with acute watery diarrhea. Crystal VCTM (Span diagnostics, India) and Cholkit (locally produced RDT) have been used to detect V. cholerae from stool samples. Samples have also been sent to the main laboratory at icddr,b where the culture based isolation is routinely performed. All the tests were carried out for both direct and enriched stool samples. RDT sensitivity and specificity were calculated using stool culture as the gold standard. RESULTS: A total of 7720 samples were tested. Among these, 5865 samples were solely tested with Crystal VC and 1355 samples with Cholkit whereas 381 samples were tested with both the RDTs. In comparison with culture, direct testing with Crystal VC showed a sensitivity of 72% (95% CI: 50.6% to 87.9%) and specificity of 86.8% (95% CI: 82.8% to 90.1%). After enrichment the sensitivity and specificity was 68% (95% CI: 46.5% to 85.1%) and 97.5% (95% CI: 95.3% to 98.8%) respectively. The direct Cholkit test showed sensitivity of 76% (95% CI: 54.9% to 90.6%) and specificity of 90.2% (95% CI: 86.6% to 93.1%). CONCLUSION: This evaluation has demonstrated that the sensitivity and specificity of Cholkit is similar to the commercially available test, Crystal VC when used in field settings for detecting V. cholerae from stool specimens. The findings from this study suggest that the Cholkit could be a possible alternative for cholera endemic regions where V. cholerae O1 is the major causative organism causing cholera.


Assuntos
Cólera/diagnóstico , Vibrio cholerae/isolamento & purificação , Adolescente , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/imunologia , Bangladesh , Criança , Pré-Escolar , Diarreia , Diagnóstico Precoce , Fezes/microbiologia , Feminino , Humanos , Masculino , Antígenos O/análise , Antígenos O/imunologia , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Sorotipagem
20.
J Med Virol ; 90(4): 677-684, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29244212

RESUMO

Human adenoviruses (HAdVs) are common cause of nonbacterial acute gastroenteritis worldwide. Limited data exist on HAdVs molecular epidemiology associated with acute gastroenteritis in Bangladesh. We describe the genetic diversity and epidemiology of HAdVs among hospitalized diarrhea patients, including HAdV genotypes, clinical symptoms, and co-infecting enteric pathogens. Stool samples were collected from ongoing diarrhea surveillance during 2012-2015. HAdV was detected using PCR and genotyped by sequencing and phylogenetic analysis. Detailed socio-demographic and clinical information regarding each individual was recorded such as duration of diarrhea, dehydration status, vomiting, abdominal pain, fever, and severity. Of 871 fecal specimens, HAdV DNA was detected in 93 (10.7%). Among them 56% were co-infected with other known enteric viral and bacterial pathogens and 31.6% had severe gastroenteritis. The majority (55%) of HAdV positives were children <5 years of age. Two main clinical symptoms in HAdV infected patients were diarrhea and vomiting. HAdVs were detected throughout the year with low prevalence in winter (November-January). Five HAdV species (A, B, C, D, and F) including 17 different genotypes were identified during the study period, with enteric HAdV species F (HAdV-40/41) being the most dominant. However, non-enteric HAdV were also detected in substantial proportion of specimens (15% species C, 15% species D, 10.8% species A, and 4.3% species B). Our study demonstrates high genetic diversity of HAdVs including enteric and non-enteric HAdVs among diarrhea patients and provides a foundation for further clarification of the role of non-enteric HAdVs in diarrheal diseases.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/classificação , Adenovírus Humanos/isolamento & purificação , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Infecções por Adenovirus Humanos/patologia , Adenovírus Humanos/genética , Adolescente , Adulto , Idoso , Bangladesh/epidemiologia , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/patologia , Coinfecção/virologia , Fezes/virologia , Feminino , Gastroenterite/patologia , Variação Genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Adulto Jovem
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