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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 2015Maternal infection with cholera may negatively affect pregnancy outcomes. The objective of this research is to systematically review the literature and determine the... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Maternal infection with cholera may negatively affect pregnancy outcomes. The objective of this research is to systematically review the literature and determine the risk of fetal, neonatal and maternal death associated with cholera during pregnancy.
MATERIALS AND METHODS
Medline, Global Health Library, and Cochrane Library databases were searched using the key terms cholera and pregnancy for articles published in any language and at any time before August 2013 to quantitatively summarize estimates of fetal, maternal, and neonatal mortality. 95% confidence intervals (CIs) were calculated for each selected study. Random-effect non-linear logistic regression was used to calculate pooled rates and 95% CIs by time period. Studies from the recent period (1991-2013) were compared with studies from 1969-1990. Relative risk (RR) estimates and 95% CIs were obtained by comparing mortality of selected recent studies with published national normative data from the closest year.
RESULTS
The meta-analysis included seven studies that together involved 737 pregnant women with cholera from six countries. The pooled fetal death rate for 4 studies during 1991-2013 was 7.9% (95% CIs 5.3-10.4), significantly lower than that of 3 studies from 1969-1990 (31.0%, 95% CIs 25.2-36.8). There was no difference in fetal death rate by trimester. The pooled neonatal death rate for 1991-2013 studies was 0.8% (95% CIs 0.0-1.6), and 6.4% (95% CIs 0.0-20.8) for 1969-1990. The pooled maternal death rate for 1991-2013 studies was 0.2% (95% CIs 0.0-0.7), and 5.0% (95% CIs 0.0-16.0) for 1969-1990. Compared with published national mortality estimates, the RR for fetal death of 5.8 (95% CIs 2.9-11.3) was calculated for Haiti (2013), 1.8 (95% CIs 0.3-10.4) for Senegal (2007), and 2.6 (95% CIs 0.5-14.9) for Peru (1991); there were no significant differences in the RR for neonatal or maternal death.
CONCLUSION
Results are limited by the inconsistencies found across included studies but suggest that maternal cholera is associated with adverse pregnancy outcomes, particularly fetal death. These findings can inform a research agenda on cholera in pregnancy and guidance for the timely management of pregnant women with cholera.
Topics: Cholera; Female; Fetal Mortality; Haiti; Humans; India; Infant; Infant Mortality; Infant, Newborn; Maternal Mortality; Pakistan; Peru; Pregnancy; Pregnancy Complications, Infectious; Pregnancy Outcome; Senegal
PubMed: 26177291
DOI: 10.1371/journal.pone.0132920 -
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 -
The Journal of Infectious Diseases Oct 2018Water, sanitation, and hygiene are one part of a cholera control strategy. Household water treatment (HWT) in particular has been shown to improve the microbiological...
Water, sanitation, and hygiene are one part of a cholera control strategy. Household water treatment (HWT) in particular has been shown to improve the microbiological quality of stored water and reduce the disease burden. We conducted a systematic review of published and gray literature to determine the outcomes and impacts of HWT in preventing cholera specifically. Fourteen manuscripts with 18 evaluations of HWT interventions in cholera were identified. Overall, a moderate quality of evidence suggests that HWT interventions reduce the burden of disease in cholera outbreaks and the risk of disease transmission. Appropriate training for users and community health worker follow-up are necessary for use. Barriers to uptake include taste and odor concerns, and facilitators include prior exposure, ease of use, and links to preexisting development programming. Further research on local barriers and facilitators, HWT filters, scaling up existing development programs, program sustainability, integrating HWT and oral cholera vaccine, and monitoring in low-access emergencies is recommended.
Topics: Cholera; Disease Outbreaks; Humans; Hygiene; Sanitation; Water; Water Purification
PubMed: 30215739
DOI: 10.1093/infdis/jiy488 -
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 -
Annali Di Igiene : Medicina Preventiva... 2019Cholera, an acute diarrheal disease caused by Vibrio cholerae (V. cholerae), is an endemic disease and a major public health problem in Iran. Antibiotic therapy can... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Cholera, an acute diarrheal disease caused by Vibrio cholerae (V. cholerae), is an endemic disease and a major public health problem in Iran. Antibiotic therapy can decrease duration of the disease, transmission of infection and contamination of the environment. Considering different pattern of V. cholerae antibiotic resistance around the world, the aim of the current systematic review and meta-analysis was to evaluate the prevalence of antibiotic resistance of V. cholerae in Iran.
METHODS
A systematic review of the literature was performed using related keywords in the electronic national and international databases including SID, Irandoc, Iran Medex and Magiran as well as PubMed, Scopus, Google Scholar and ISI web of knowledge. Up to July 31, 2018, 27 eligible papers were included in our meta-analysis based on the defined inclusion criteria.
RESULTS
V. cholerae O1 was the most prevalent strain isolated in Iran and exhibited a high resistance rate against numerous antibiotics including chloramphenicol (33.6%), oxytetracycline (40.2%), trimethoprim/sulphamethoxazole (86%), tetracycline (34.5%), furazolidone (69.8%), streptomycin (93.8%), polymyxin (80.7%), ampicillin (32.1%), nalidixic acid (88.9%), kanamycin (29%) and amoxicillin (30.5%).
CONCLUSIONS
According to the meta-analysis results, antibiotic therapy with ciprofloxacin, doxycycline, erythromycin, gentamicin, azithromycin, cefixime and cefepime could be effective for the treatment of severe cases of cholera in Iran.
Topics: Anti-Bacterial Agents; Cholera; Drug Resistance, Microbial; Drug Resistance, Multiple, Bacterial; Humans; Iran; Vibrio cholerae; Vibrio cholerae O1
PubMed: 31069372
DOI: 10.7416/ai.2019.229 -
The Lancet. Infectious Diseases Oct 2017Killed whole-cell oral cholera vaccines (kOCVs) are becoming a standard cholera control and prevention tool. However, vaccine efficacy and direct effectiveness estimates... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Killed whole-cell oral cholera vaccines (kOCVs) are becoming a standard cholera control and prevention tool. However, vaccine efficacy and direct effectiveness estimates have varied, with differences in study design, location, follow-up duration, and vaccine composition posing challenges for public health decision making. We did a systematic review and meta-analysis to generate average estimates of kOCV efficacy and direct effectiveness from the available literature.
METHODS
For this systematic review and meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Review Library on July 9, 2016, and ISI Web of Science on July 11, 2016, for randomised controlled trials and observational studies that reported estimates of direct protection against medically attended confirmed cholera conferred by kOCVs. We included studies published on any date in English, Spanish, French, or Chinese. We extracted from the published reports the primary efficacy and effectiveness estimates from each study and also estimates according to number of vaccine doses, duration, and age group. The main study outcome was average efficacy and direct effectiveness of two kOCV doses, which we estimated with random-effect models. This study is registered with PROSPERO, number CRD42016048232.
FINDINGS
Seven trials (with 695 patients with cholera) and six observational studies (217 patients with cholera) met the inclusion criteria, with an average two-dose efficacy of 58% (95% CI 42-69, I=58%) and effectiveness of 76% (62-85, I=0). Average two-dose efficacy in children younger than 5 years (30% [95% CI 15-42], I=0%) was lower than in those 5 years or older (64% [58-70], I=0%; p<0·0001). Two-dose efficacy estimates of kOCV were similar during the first 2 years after vaccination, with estimates of 56% (95% CI 42-66, I=45%) in the first year and 59% (49-67, I=0) in the second year. The efficacy reduced to 39% (13 to 57, I=48%) in the third year, and 26% (-46 to 63, I=74%) in the fourth year.
INTERPRETATION
Two kOCV doses provide protection against cholera for at least 3 years. One kOCV dose provides at least short-term protection, which has important implications for outbreak management. kOCVs are effective tools for cholera control.
FUNDING
The Bill & Melinda Gates Foundation.
Topics: Administration, Oral; Cholera; Cholera Vaccines; Humans; Vaccines, Inactivated
PubMed: 28729167
DOI: 10.1016/S1473-3099(17)30359-6 -
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 -
Bulletin of the World Health... Dec 2014To describe and analyse the characteristics of oral cholera vaccination campaigns; including location, target population, logistics, vaccine coverage and delivery costs. (Review)
Review
OBJECTIVE
To describe and analyse the characteristics of oral cholera vaccination campaigns; including location, target population, logistics, vaccine coverage and delivery costs.
METHODS
We searched PubMed, the World Health Organization (WHO) website and the Cochrane database with no date or language restrictions. We contacted public health personnel, experts in the field and in ministries of health and did targeted web searches.
FINDINGS
A total of 33 documents were included in the analysis. One country, Viet Nam, incorporates oral cholera vaccination into its public health programme and has administered approximately 10.9 million vaccine doses between 1997 and 2012. In addition, over 3 million doses of the two WHO pre-qualified oral cholera vaccines have been administered in more than 16 campaigns around the world between 1997 and 2014. These campaigns have either been pre-emptive or reactive and have taken place under diverse conditions, such as in refugee camps or natural disasters. Estimated two-dose coverage ranged from 46 to 88% of the target population. Approximate delivery cost per fully immunized person ranged from 0.11-3.99 United States dollars.
CONCLUSION
Experience with oral cholera vaccination campaigns continues to increase. Public health officials may draw on this experience and conduct oral cholera vaccination campaigns more frequently.
Topics: Administration, Oral; Cholera; Cholera Vaccines; Global Health; Humans; Immunization Programs; Public Health Practice; Vietnam; World Health Organization
PubMed: 25552772
DOI: 10.2471/BLT.14.139949 -
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