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Clinical Microbiology and Infection :... Feb 2022Cholera is an acute diarrheal disease caused by Vibrio cholerae O1 or O139. Cholera rapid diagnostic tests (RDTs) are widely used to screen for cholera cases. However,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cholera is an acute diarrheal disease caused by Vibrio cholerae O1 or O139. Cholera rapid diagnostic tests (RDTs) are widely used to screen for cholera cases. However, their accuracy has not been systematically reviewed.
OBJECTIVES
To evaluate the diagnostic accuracy of cholera RDTs.
METHODS
Systematic review and meta-analysis.
DATA SOURCES
Medline, EMBASE and Web of science through to November 2020; references of included studies and a technical guidance on cholera RDTs. This review is registered with PROSPERO (CRD42021233124).
STUDY ELIGIBILITY CRITERIA
Cross-sectional studies comparing the performance of cholera RDTs either to stool culture or PCR.
PARTICIPANTS
Individuals with clinically suspected cholera.
DATA EXTRACTION
Two authors independently extracted data and assessed the quality using Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) criteria.
RESULTS
Eighteen studies were included in the systematic review of which 17 were used for meta-analysis. Crystal VC was the most frequently used RDT (13 studies), followed by Cholkit and Institut Pasteur cholera dipstick (three studies each), SD Bioline (two studies), Artron (one study) and Smart (one study). Using direct testing (n = 12 627 specimens), the bivariate random-effects model yielded a pooled sensitivity and specificity of 91% (95% CI 87%-94%) and 80% (95% CI 74%-84%), respectively. However, through alkaline peptone water (APW) enrichment (n = 3403 specimens), the pooled sensitivity and specificity were 89% (95% CI 79%-95%) and 98% (95% CI 95%-99%), respectively.
CONCLUSION
Cholera RDTs, especially when enriched with APW, have moderate sensitivity and specificity. Although less useful for clinical management, the current generation of RDTs have clear utility for surveillance efforts if used in a principled manner. Enrichment of stool specimens in APW before using cholera RDTs reduces the possibility of obtaining false-positive results, despite the few cholera cases that go undetected. It is noteworthy that APW-enriched cholera RDTs are not necessarily rapid tests, and are not listed in the Global Task Force on Cholera Control/WHO target product profile.
Topics: Cholera; Cross-Sectional Studies; Humans; Reagent Kits, Diagnostic; Sensitivity and Specificity; Vibrio cholerae O1
PubMed: 34506946
DOI: 10.1016/j.cmi.2021.08.027 -
International Journal of Environmental... Jun 2022Approximately 2.9 million people worldwide suffer from cholera each year, many of whom are destitute. However, understanding of immunity against cholera is still... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Approximately 2.9 million people worldwide suffer from cholera each year, many of whom are destitute. However, understanding of immunity against cholera is still limited. Several studies have reported the duration of antibodies following cholera; however, systematic reviews including a quantitative synthesis are lacking.
OBJECTIVE
To meta-analyze cohort studies that have evaluated vibriocidal, cholera toxin B subunit (CTB), and lipopolysaccharide (LPS) antibody levels following a clinical cholera case.
METHODS
Design: Systematic review and meta-analysis. We searched PubMed and Web of science for studies assessing antibodies against in cohorts of patients with clinical cholera. Two authors independently extracted data and assessed the quality of included studies. Random effects models were used to pool antibody titers in adults and older children (aged ≥ 6 years). In sensitivity analysis, studies reporting data on young children (2-5 years) were included.
RESULTS
Nine studies met our inclusion criteria for systematic review and seven for meta-analysis. The pooled mean of vibriocidal antibody titers in adults and older children (aged ≥ 6 years) was 123 on day 2 post-symptom onset, which sharply increased on day 7 (pooled mean = 6956) and gradually waned to 2247 on day 30, 578 on day 90, and 177 on day 360. Anti-CTB IgA antibodies also peaked on day 7 (pooled mean = 49), followed by a rapid decrease on day 30 (pooled mean = 21), and further declined on day 90 (pooled mean = 10), after which it plateaued from day 180 (pooled mean = 8) to 360 (pooled mean = 6). Similarly, anti-CTB IgG antibodies peaked in early convalescence between days 7 (pooled mean = 65) and 30 (pooled mean = 69), then gradually waned on days 90 (pooled mean = 42) and 180 (pooled mean = 30) and returned to baseline on day 360 (pooled mean = 24). Anti-LPS IgA antibodies peaked on day 7 (pooled mean = 124), gradually declined on day 30 (pooled mean = 44), which persisted until day 360 (pooled mean = 10). Anti LPS IgG antibodies peaked on day 7 (pooled mean = 94). Thereafter, they decreased on day 30 (pooled mean = 85), and dropped further on days 90 (pooled mean = 51) and 180 (pooled mean = 47), and returned to baseline on day 360 (pooled mean = 32). Sensitivity analysis including data from young children (aged 2-5 years) showed very similar findings as in the primary analysis.
CONCLUSIONS
This study confirms that serological antibody (vibriocidal, CTB, and LPS) titers return to baseline levels within 1 year following clinical cholera, i.e., before the protective immunity against subsequent cholera wanes. However, this decay should not be interpreted as waning immunity because immunity conferred by cholera against subsequent disease lasts 3-10 years. Our study provides evidence for surveillance strategies and future research on vaccines and also demonstrates the need for further studies to improve our understanding of immunity against cholera.
Topics: Adolescent; Adult; Antibodies, Bacterial; B-Lymphocytes; Child; Child, Preschool; Cholera; Humans; Immunoglobulin A; Immunoglobulin G; Immunologic Memory; Kinetics; Lipopolysaccharides; Vibrio cholerae O1
PubMed: 35742404
DOI: 10.3390/ijerph19127141 -
Mathematical Biosciences Jul 2024Diverse modelling techniques in cholera epidemiology have been developed and used to (1) study its transmission dynamics, (2) predict and manage cholera outbreaks, and... (Review)
Review
Diverse modelling techniques in cholera epidemiology have been developed and used to (1) study its transmission dynamics, (2) predict and manage cholera outbreaks, and (3) assess the impact of various control and mitigation measures. In this study, we carry out a critical and systematic review of various approaches used for modelling the dynamics of cholera. Also, we discuss the strengths and weaknesses of each modelling approach. A systematic search of articles was conducted in Google Scholar, PubMed, Science Direct, and Taylor & Francis. Eligible studies were those concerned with the dynamics of cholera excluding studies focused on models for cholera transmission in animals, socio-economic factors, and genetic & molecular related studies. A total of 476 peer-reviewed articles met the inclusion criteria, with about 40% (32%) of the studies carried out in Asia (Africa). About 52%, 21%, and 9%, of the studies, were based on compartmental (e.g., SIRB), statistical (time series and regression), and spatial (spatiotemporal clustering) models, respectively, while the rest of the analysed studies used other modelling approaches such as network, machine learning and artificial intelligence, Bayesian, and agent-based approaches. Cholera modelling studies that incorporate vector/housefly transmission of the pathogen are scarce and a small portion of researchers (3.99%) considers the estimation of key epidemiological parameters. Vaccination only platform was utilized as a control measure in more than half (58%) of the studies. Research productivity in cholera epidemiological modelling studies have increased in recent years, but authors used diverse range of models. Future models should consider incorporating vector/housefly transmission of the pathogen and on the estimation of key epidemiological parameters for the transmission of cholera dynamics.
Topics: Cholera; Humans; Epidemiological Models; Disease Outbreaks
PubMed: 38777029
DOI: 10.1016/j.mbs.2024.109210 -
Journal of Infection in Developing... Dec 2023Diarrhoeas, acute gastroenteritis with moderate dehydration, malaria and cholera are water-borne diseases with a high incidence in childhood and are one of the principal... (Review)
Review
INTRODUCTION
Diarrhoeas, acute gastroenteritis with moderate dehydration, malaria and cholera are water-borne diseases with a high incidence in childhood and are one of the principal causes of morbidity and mortality in children under the age of 5 years, and predominantly so in developing countries. Various factors influence the population's vulnerability to these diseases. The objective of this work was to identify the factors of socio-environmental vulnerability associated with the occurrence of water-borne diseases (diarrhoeas, acute gastroenteritis with moderate dehydration, malaria and cholera).
METHODOLOGY
A systematic review of the literature was performed, with the databases PubMed, Scopus, B-On and Scielo to identify studies published between 2010 and 2021.
RESULTS AND CONCLUSIONS
The results showed that the most significant factors related to vulnerability to water-borne diseases have to do with sanitation and the availability of clean drinking water; however, temperature and precipitation were also found to exert considerable influence, together with the demographic factor.
Topics: Child; Humans; Child, Preschool; Cholera; Dehydration; Diarrhea; Gastroenteritis; Malaria; Water
PubMed: 38252714
DOI: 10.3855/jidc.18210 -
Expert Review of Clinical Immunology Dec 2022Cholera is an enteric disease caused by , a water-borne pathogen, and characterized by severe diarrhea. Vaccines have been recommended for use by the WHO in...
INTRODUCTION
Cholera is an enteric disease caused by , a water-borne pathogen, and characterized by severe diarrhea. Vaccines have been recommended for use by the WHO in resource-limited settings. Efficacies of the currently licensed cholera vaccines are not optimal in endemic settings and low in children below the age of five, a section of the population most susceptible to the disease. Development of next generation of cholera vaccines would require a detailed understanding of the required protective immune responses.
AREA COVERED
In this review, we revisit clinical trials which are focused on the early transcriptional mucosal responses elicited during infection and upon vaccination along with summarizing various components of the effector immune response against .
EXPERT OPINION
The inability of currently licensed killed/inactivated vaccines to elicit key inflammatory pathways locally may explain their restricted efficacy in endemic settings. More studies are required to understand the immunogenicity of the live attenuated cholera vaccine in these regions. Various extrinsic and intrinsic factors influence anti-cholera immunity and need to be considered to develop region-specific next generation vaccines.
Topics: Child; Humans; Administration, Oral; Antibodies, Bacterial; Cholera; Cholera Vaccines; Immunity; Vaccines, Attenuated; Vibrio cholerae
PubMed: 36255170
DOI: 10.1080/1744666X.2022.2136650 -
PloS One 2022Cholera continues to pose a problem for low-resource, fragile and humanitarian contexts. Evidence suggests that 2.86 million cholera cases and 95,000 deaths due to... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Cholera continues to pose a problem for low-resource, fragile and humanitarian contexts. Evidence suggests that 2.86 million cholera cases and 95,000 deaths due to cholera are reported annually. Without quick and effective diagnosis and treatment, case-fatality may be 50%. In line with the priorities of the Global Task Force on Cholera Control, we undertook a systematic review and meta-analysis of diagnostic test accuracy and other test characteristics of current tests for cholera detection in stool and water.
METHODS
We searched 11 bibliographic and grey literature databases. Data was extracted on test sensitivity, specificity and other product information. Meta-analyses of sensitivity and specificity were conducted for tests reported in three or more studies. Where fewer studies reported a test, estimates were summarised through narrative synthesis. Risk of Bias was assessed using QUADAS-2.
RESULTS
Searches identified 6,637 records; 41 studies reporting on 28 tests were included. Twenty-two tests had both sensitivities and specificities reported above 95% by at least one study, but there was, overall, wide variation in reported diagnostic accuracy across studies. For the three tests where meta-analyses were possible the highest sensitivity meta-estimate was found in the Cholera Screen test (98.6%, CI: 94.7%-99.7%) and the highest specificity meta-estimate in the Crystal VC on enriched samples (98.3%, CI: 92.8%-99.6%). There was a general lack of evidence regarding field use of tests, but where presented this indicated trends for lower diagnostic accuracy in field settings, with lesser-trained staff, and without the additional process of sample enrichment. Where reported, mean test turnaround times ranged from over 50% to 130% longer than manufacturer's specification. Most studies had a low to unclear risk of bias.
CONCLUSIONS
Currently available Rapid Diagnostic Tests can potentially provide high diagnostic and detection capability for cholera. However, stronger evidence is required regarding the conditions required to secure these levels of accuracy in field use, particularly in low-resource settings.
REGISTRATION
PROSPERO (CRD42016048428).
Topics: Advisory Committees; Cholera; Databases, Factual; Feces; Humans; Water
PubMed: 35793330
DOI: 10.1371/journal.pone.0270860 -
Journal of Travel Medicine Dec 2019Exposure to cholera is a risk for individuals and groups travelling to endemic areas, and the bacteria can be imported to cholera-free countries by returning travellers....
Exposure to cholera is a risk for individuals and groups travelling to endemic areas, and the bacteria can be imported to cholera-free countries by returning travellers. This systematic review of the literature describes the circumstances in which cholera infection can occur in travellers and considers the possible value of the cholera vaccine for prevention in travellers. PubMed and EMBASE were searched for case reports of cholera or diarrhoea among travellers, with date limits of 1 January 1990-30 April 2018. Search results were screened to exclude the following articles: diarrhoea not caused by cholera, cholera in animals, intentional cholera infection in humans, non-English articles and publications on epidemics that did not report clinical details of individual cases and publications of cases pre-dating 1990. Articles were reviewed through descriptive analytic methods and information summarized. We identified 156 cases of cholera imported as a consequence of travel, and these were reviewed for type of traveller, source country, serogroup of cholera, treatment and outcomes. The case reports retrieved in the search did not report consistent levels of detail, making it difficult to synthesize data across reports and draw firm conclusions from the data. This clinical review sheds light on the paucity of actionable published data regarding the risk of cholera in travellers and identifies a number of gaps that should drive additional effort. Further information is needed to better inform evidence-based disease prevention strategies, including vaccination for travellers visiting areas of cholera risk. Modifications to current vaccination recommendations to include or exclude current or additional traveller populations may be considered as additional risk data become available. The protocol for this systematic review is registered with PROSPERO (registration number: 122797).
Topics: Cholera; Cholera Vaccines; Humans; Travel; Vaccination
PubMed: 31804684
DOI: 10.1093/jtm/taz085 -
Revista Espanola de Salud Publica Nov 2021The humanitarian response to a cholera outbreak in a complex international crisis requires guaranteeing minimum conditions so that normalcy can be restored. Basic... (Review)
Review
BACKGROUND
The humanitarian response to a cholera outbreak in a complex international crisis requires guaranteeing minimum conditions so that normalcy can be restored. Basic responses to a cholera outbreak include water and sanitation. The general objective of this systematic review was the analysis of the current evidence that addresses the effectiveness of different WASH measures to control cholera.
METHODS
A review and analysis of the literature available in the main databases (PubMed, WoS and Scopus) and in a specific meta-search engine for humanitarian aid was carried out (reliefweb.int). Based on the establishment of the PICO research question "", the identification of keywords and databases to carry out the searches, as well as a selection process based on the established eligibility criteria: being studies in both English and Spanish where the WASH intervention was clearly defined, studies where health outcomes of cholera were presented, or data related to the function and use of the WASH intervention, was established.
RESULTS
The initial search provided 17,185 documents susceptible of analysis that were screened using the search criteria, up to 22 references that were read in full text and the 11 that were finally analyzed. These were coded based on the measures set out in their protocols, on the interventions carried out in the improvement of water and its supply, the improvement of sanitation, the measures aimed at better hygiene and those that evaluated the complete WASH intervention.
CONCLUSIONS
All the measures offered positive results, their effectiveness was conditioned by the education of the beneficiaries, the simplicity of the activities and the involvement of local actors.
Topics: Cholera; Disease Outbreaks; Humans; Hygiene; Sanitation; Spain
PubMed: 34732687
DOI: No ID Found -
Antimicrobial Resistance and Infection... Apr 2022Vibrio cholerae O1/O139 were the predominant circulating serogroups exhibiting multi-drug resistance (MDR) during the cholera outbreak which led to cholera treatment... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Vibrio cholerae O1/O139 were the predominant circulating serogroups exhibiting multi-drug resistance (MDR) during the cholera outbreak which led to cholera treatment failures.
OBJECTIVE
This meta-analysis aimed to evaluate the weighted pooled resistance (WPR) rates in V. cholerae O1/O139 isolates obtained from environmental samples.
METHODS
We systematically searched the articles in PubMed, Scopus, and Embase (until January 2020). Subgroup analyses were then employed by publication year, geographic areas, and the quality of studies. Statistical analyses were conducted using STATA software (ver. 14.0).
RESULTS
A total of 20 studies investigating 648 environmental V. cholerae O1/O139 isolates were analysed. The majority of the studies were originated from Asia (n = 9). In addition, a large number of studies (n = 15 i.e. 71.4%) included in the meta-analysis revealed the resistance to cotrimoxazole and ciprofloxacin. The WPR rates were as follows: cotrimoxazole 59%, erythromycin 28%, tetracycline 14%, doxycycline 5%, and ciprofloxacin 0%. There was increased resistance to nalidixic acid, cotrimoxazole, furazolidone, and tetracycline while a decreased resistance to amoxicillin, ciprofloxacin, erythromycin, chloramphenicol, ampicillin, streptomycin, and ceftriaxone was observed during the years 2000-2020. A significant decrease in the doxycycline and ciprofloxacin-resistance rates in V. cholerae O1/O139 isolates was reported over the years 2011-2020 which represents a decrease in 2001-2010 (p < 0.05).
CONCLUSIONS
Fluoroquinolones, gentamicin, ceftriaxone, doxycycline, kanamycin, and cefotaxime showed the highest effectiveness and the lowest resistance rate. However, the main interest is the rise of antimicrobial resistance in V. cholerae strains especially in low-income countries or endemic areas, and therefore, continuous surveillance, careful appropriate AST, and limitation on improper antibiotic usage are crucial.
Topics: Anti-Bacterial Agents; Ceftriaxone; Cholera; Ciprofloxacin; Doxycycline; Drug Resistance, Bacterial; Erythromycin; Humans; Microbial Sensitivity Tests; Trimethoprim, Sulfamethoxazole Drug Combination; Vibrio cholerae O1; Vibrio cholerae O139
PubMed: 35468830
DOI: 10.1186/s13756-022-01100-3 -
The Cochrane Database of Systematic... Jan 2024Cholera causes acute watery diarrhoea and death if not properly treated. Outbreaks occur in areas with poor sanitation, including refugee camps. Several vaccines have... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cholera causes acute watery diarrhoea and death if not properly treated. Outbreaks occur in areas with poor sanitation, including refugee camps. Several vaccines have been developed and tested over the last 50 years. This is an update of a Cochrane review, originally published in 1998, which explored the effects of all vaccines for preventing cholera. This review examines oral vaccines made from killed bacteria.
OBJECTIVES
To assess the effectiveness and safety of the available World Health Organization (WHO)-prequalified oral killed cholera vaccines among children and adults.
SEARCH METHODS
We searched the Cochrane Infectious Diseases Group Specialized Register; CENTRAL, MEDLINE; Embase; LILACS; and two trials registers (February 2023).
SELECTION CRITERIA
We included randomized controlled trials (RCTs), including cluster-RCTs. There were no restrictions on the age and sex of the participants or the setting of the study. We considered any available WHO-prequalified oral killed cholera vaccine as an intervention. The control group was given a placebo, another vaccine, or no vaccine. The outcomes were related to vaccine effectiveness and safety. We included articles published in English only.
DATA COLLECTION AND ANALYSIS
Two review authors independently applied the inclusion criteria and extracted data from included studies. We assessed the risk of bias using the Cochrane ROB 1 assessment tool. We used the generic inverse variance and a random-effects model meta-analysis to estimate the pooled effect of the interventions. We assessed the certainty of the evidence using the GRADE approach. For vaccine effectiveness (VE), we converted the overall risk ratio (RR) to vaccine effectiveness using the formula: VE = (1 - RR) x 100%.
MAIN RESULTS
Five RCTs, reported in 12 records, with 462,754 participants, met the inclusion criteria. We identified trials on whole-cell plus recombinant vaccine (WC-rBS vaccine (Dukoral)) from Peru and trials on bivalent whole-cell vaccine (BivWC (Shanchol)) vaccine from India and Bangladesh. We did not identify any trials on other BivWC vaccines (Euvichol/Euvichol-Plus), or Hillchol. Two doses of Dukoral with or without a booster dose reduces cases of cholera at two-year follow-up in a general population of children and adults, and at five-month follow-up in an adult male population (overall VE 76%; RR 0.24, 95% confidence interval (CI) 0.08 to 0.65; 2 trials, 16,423 participants; high-certainty evidence). Two doses of Shanchol reduces cases of cholera at one-year follow-up (overall VE 37%; RR 0.63, 95% CI 0.47 to 0.85; 2 trials, 241,631 participants; high-certainty evidence), at two-year follow-up (overall VE 64%; RR 0.36, 95% CI 0.16 to 0.81; 2 trials, 168,540 participants; moderate-certainty evidence), and at five-year follow-up (overall VE 80%; RR 0.20, 95% CI 0.15 to 0.26; 1 trial, 54,519 participants; high-certainty evidence). A single dose of Shanchol reduces cases of cholera at six-month follow-up (overall VE 40%; RR 0.60, 95% CI 0.47 to 0.77; 1 trial, 204,700 participants; high-certainty evidence), and at two-year follow-up (overall VE 39%; RR 0.61, 95% CI 0.53 to 0.70; 1 trial, 204,700 participants; high-certainty evidence). A single dose of Shanchol also reduces cases of severe dehydrating cholera at six-month follow-up (overall VE 63%; RR 0.37, 95% CI 0.28 to 0.50; 1 trial, 204,700 participants; high-certainty evidence), and at two-year follow-up (overall VE 50%; RR 0.50, 95% CI 0.42 to 0.60; 1 trial, 204,700 participants; high-certainty evidence). We found no differences in the reporting of adverse events due to vaccination between the vaccine and control/placebo groups.
AUTHORS' CONCLUSIONS
Two doses of Dukoral reduces cases of cholera at two-year follow-up. Two doses of Shanchol reduces cases of cholera at five-year follow-up, and a single dose of Shanchol reduces cases of cholera at two-year follow-up. Overall, the vaccines were safe and well-tolerated. We found no trials on other BivWC vaccines (Euvichol/Euvichol-Plus). However, BivWC products (Shanchol, Euvichol/Euvichol-Plus) are considered to produce comparable vibriocidal responses. Therefore, it is reasonable to apply the results from Shanchol trials to the other BivWC products (Euvichol/Euvichol-Plus).
Topics: Adult; Child; Male; Humans; Cholera Vaccines; Cholera; Vaccines, Inactivated; Vaccination; Bangladesh; Diarrhea
PubMed: 38197546
DOI: 10.1002/14651858.CD014573