Recent Cholera Publications on PubMed

The impact of improved water supply on cholera and diarrhoeal diseases in Uvira, Democratic Republic of the Congo: a protocol for a pragmatic stepped-wedge cluster randomised trial and economic evaluation

June 22, 2021

Trials. 2021 Jun 21;22(1):408. doi: 10.1186/s13063-021-05249-x.

ABSTRACT

INTRODUCTION: Diarrhoeal disease remains a leading cause of mortality and morbidity worldwide. Cholera alone is estimated to cause 95,000 deaths per year, most of which occur in endemic settings with inadequate water access. Whilst a global strategy to eliminate cholera by 2030 calls for investment in improved drinking water services, there is limited rigorous evidence for the impact of improved water supply on endemic cholera transmission in low-income urban settings. Our protocol is designed to deliver a pragmatic health impact evaluation of a large-scale water supply intervention in Uvira (Democratic Republic of the Congo), a cholera transmission hotspot.

METHODS/DESIGN: A stepped-wedge cluster randomised trial (SW-CRT) was designed to evaluate the impact of a large-scale drinking water supply intervention on cholera incidence among the 280,000 inhabitants of Uvira. The city was divided into 16 clusters, where new community and household taps will be installed following a randomised sequence over a transition period of up to 8 weeks in each cluster. The primary trial outcomes are the monthly incidence of "confirmed" cholera cases (patients testing positive by rapid detection kit) and of "suspected" cholera cases (patients admitted to the cholera treatment centre). Concurrent process and economic evaluations will provide further information on the context, costs, and efficiency of the intervention.

DISCUSSION: In this protocol, we describe a pragmatic approach to conducting rigorous research to assess the impacts of a complex water supply intervention on severe diarrhoeal disease and cholera in an unstable, low-resource setting representative of cholera-affected areas. In particular, we discuss a series of pre-identified risks and linked mitigation strategies as well as the value of combining different data collection methods and preparation of multiple analysis scenarios to account for possible deviations from the protocol. The study described here has the potential to provide robust evidence to support more effective cholera control in challenging, high-burden settings.

TRIAL REGISTRATION: This trial is registered on clinicaltrials.gov ( NCT02928341 , 10th October 2016) and has received ethics approval from the London School of Hygiene and Tropical Medicine (8913, 10603) and from the Ethics Committee from the School of Public Health, University of Kinshasa, Democratic Republic of the Congo (ESP/CE/088/2015).

PMID:34154636 | DOI:10.1186/s13063-021-05249-x

Characterization of V. cholerae O1 biotype El Tor serotype Ogawa possessing the ctxB gene of the classical biotype isolated from well water associated with the cholera outbreak in Kerala, South India

June 21, 2021

J Water Health. 2021 Jun;19(3):478-487. doi: 10.2166/wh.2021.263.

ABSTRACT

We investigated 22 water samples (17 well water and five pipe water - both chlorinated) and six soil samples from the surroundings of wells of the households of suspected patients from Palakkad district, Kerala (India), from where a cholera outbreak was reported during June-July 2016. A total of 25 Vibrio cholerae isolates were collected from three well water samples during a recent cholera outbreak. Biochemical and serological studies revealed that all of the isolates belonged to serogroup O1, biotype El Tor, serotype Ogawa. PCR assays confirmed the occurrence of ctxB, ctxA, hlyA, tcpA El Tor,VPI, ace, zot, ompW, rfbO1 and toxR genes in all isolates. The presence of the ctxB gene of the classical biotype in all of the El Tor isolates suggests that it is a new variant of El Tor biotype. Antibiogram profile of all V. cholerae O1 isolates revealed resistance towards five classes of antibiotics island and indicates that they were multidrug resistant. ERIC-PCR and PFGE finger prints showed the clonal relationship among the V. cholerae O1 isolates. The results of this study revealed the emergence of a new variant of El Tor biotype in the water samples from Palakkad district, from where a cholera outbreak was reported.

PMID:34152300 | DOI:10.2166/wh.2021.263

Moving forward with an imperfect vaccine

June 19, 2021

Lancet Infect Dis. 2021 Jun 16:S1473-3099(20)30851-3. doi: 10.1016/S1473-3099(20)30851-3. Online ahead of print.

NO ABSTRACT

PMID:34146474 | DOI:10.1016/S1473-3099(20)30851-3

Regional sequencing collaboration reveals persistence of the T12 Vibrio cholerae O1 lineage in West Africa

June 18, 2021

Elife. 2021 Jun 18;10:e65159. doi: 10.7554/eLife.65159.

ABSTRACT

BACKGROUND: Despite recent insights into cholera transmission patterns in Africa, regional and local dynamics in West Africa-where cholera outbreaks occur every few years-are still poorly understood. Coordinated genomic surveillance of Vibrio cholerae in the areas most affected may reveal transmission patterns important for cholera control.

METHODS: During a regional sequencing workshop in Nigeria, we sequenced 46 recent V. cholerae isolates from Cameroon, Niger, and Nigeria (37 from 2018 to 2019) to better understand the relationship between the V. cholerae bacterium circulating in these three countries.

RESULTS: From these isolates, we generated 44 whole Vibrio cholerae O1 sequences and analyzed them in the context of 1280 published V. cholerae O1 genomes. All sequences belonged to the T12 V. cholerae seventh pandemic lineage.

CONCLUSIONS: Phylogenetic analysis of newly generated and previously published V. cholerae genomes suggested that the T12 lineage has been continuously transmitted within West Africa since it was first observed in the region in 2009, despite lack of reported cholera in the intervening years. The results from this regional sequencing effort provide a model for future regionally coordinated surveillance efforts.

FUNDING: Funding for this project was provided by Bill and Melinda Gates Foundation OPP1195157.

PMID:34143732 | DOI:10.7554/eLife.65159

Principles of evidence-based medicine: from Robert Kochs postulates to a current EBM concept

June 17, 2021

Cas Lek Cesk. 2021 Spring;160(2-3):93-96.

ABSTRACT

The aim of the article is to describe the development of the principles of medicine based on the evidence (EBM) based on postulates of Robert Koch, Nobel prize winner, protagonist of the "Golden Age" medical bacteriology, founder of a concept of modern microbiology and infectology. Kochs work led to the discovery of a causal relationship between exposure to a specific pathogen and disease on the example of identifying the cause of anthrax - Bacillus anthracis, a disease whose symptoms vary depending on the mode of transmission (gastrointestinal ingestion, cutaneous form on contact and pulmonary manifestations when inhaled). Tuberculosis caused by Kochs bacillus, Mycobacterium tuberculosis, yet still affecting 1.7 billion people (about 25 % of the world's population), in 95 % of cases in developing countries, where poverty and high prevalence of HIV are part of everyday life. Koch also discovered Vibrio cholerae, the pathogen responsible for seven recorded pandemics, and hitherto sporadic epidemics in recent years. The main contribution of the Kochs four postulates formulation was the principle, which helped to reveal the causal relationship between the pathogenic microbe to protrude infectious disease and obtain reliable evidence in improving credibility of diagnosis of infectious diseases. Other stages in the development of EBM were formulated by Bradford Hill in his nine principles, which are valid as well for noncommunicable diseases. The subjects of discussion are limitations and restrictions of present EBM and its essentials and the use in rational preventive, diagnostic and treatment strategies.

PMID:34134498

Genetic characterization and phylogenetic variations of human adenovirus-F strains circulating in eastern India during 2017-2020

June 17, 2021

J Med Virol. 2021 Jun 17. doi: 10.1002/jmv.27136. Online ahead of print.

ABSTRACT

Human Adenovirus-F (genotype 40/41) is the second-most leading cause of paediatric gastroenteritis after rotavirus, worldwide, accounting for 2.8-11.8% of infantile diarrhoeal cases. Earlier studies across eastern India revealed a shift in the predominance of genotypes from HAdV41 in 2007-09 to HAdV40 in 2013-14. Thus, the surveillance for HAdV-F genotypes in this geographical setting was undertaken during 2017-2020 to analyse the viral evolutionary dynamics. A total of 3882 stool samples collected from children (<5 years) were screened for HAdV-F positivity by conventional PCR. The hypervariable regions of the hexon and the partial shaft region of long fiber genes were amplified, sequenced and phylogenetically analysed with respect to the prototype strains. A marginal decrease in enteric HAdV prevalence was observed (9.04%, n=351/3882) compared to the previous report (11.8%) in this endemic setting. Children <2 years were found most vulnerable to enteric HAdV infection. Reduction in adenovirus-rotavirus co-infection was evident compared to the sole adenovirus infection. HAdV-F genotypes 40 and 41 were found to co-circulate, but HAdV41 was predominant. HAdV40 strains were genetically conserved, whereas HAdV41 strains accumulated new mutations. On the basis of different set of mutations in their genome, HAdV41 strains segregated into 2 genome type clusters (GTCs). Circulating HAdV41 strains clustered with GTC1 of fiber gene, for the first time during this study period. This study will provide much needed baseline data on emergence and circulation of HAdV40/41 strains for future vaccine development. This article is protected by copyright. All rights reserved.

PMID:34138479 | DOI:10.1002/jmv.27136

Vitamin C levels in a Central-African mother-infant cohort: Does hypovitaminosis C increase the risk of enteric infections?

June 17, 2021

Matern Child Nutr. 2021 Jun 17:e13215. doi: 10.1111/mcn.13215. Online ahead of print.

ABSTRACT

In the MITICA (Mother-to-Infant TransmIssion of microbiota in Central-Africa) study, 48 mothers and their 50 infants were followed from delivery to 6 months between December 2017 and June 2019 in Bangui (Central-African Republic). Blood tests and stool analyses were performed in mothers at delivery, and their offspring at birth, 11 weeks and 25 weeks. Stool cultures were performed in specific growth media for Salmonella, Shigella, E. coli, Campylobacter, Enerobacter, Vibrio cholerae, Citrobacter and Klebsiella, as well as rotavirus, yeasts and parasitological exams. The median vitamin C levels in mothers at delivery were 15.3 μmol/L (inter-quartile-range [IQR] 6.2-27.8 μmol/L). In infants, the median vitamin C levels at birth were 35.2 μmol/L (IQR 16.5-63.9 μmol/L). At 11 and 25 weeks, the median vitamin C levels were 41.5 μmol/L (IQR 18.7-71.6 μmol/L) and 18.2 μmol/L (IQR 2.3-46.6 μmol/L), respectively. Hypovitaminosis C was defined as seric vitamin C levels <28 μmol/L and vitamin C deficiency was defined as vitamin C levels <11 μmol/L according to the WHO definition. In mothers, the prevalence of hypovitaminosis-C and vitamin C deficiency at delivery was 34/45 (75.6%) and 19/45 (42.2%), respectively. In infants, the prevalence of hypovitaminosis-C and vitamin C deficiency at 6 months was 18/33 (54.6%) and 11/33 (33.3%), respectively. Vitamin C levels in mothers and infants were correlated at birth (Spearman's rho = 0.5; P value = 0.002), and infants had significantly higher levels of vitamin C (median = 35.2 μmol/L; IQR 16.5-63.9 μmol/L), compared to mothers (median = 15.3 μmol/L; IQR 6.2-27.8 μmol/L; P value <0.001). The offspring of vitamin C-deficient mothers had significantly lower vitamin C levels at delivery (median = 18.7 μmol/L; IQR 13.3-30.7 μmol/L), compared to the offspring of non-deficient mothers (median = 62.2 μmol/L; IQR 34.6-89.2 μmol/L; P value <0.001). Infants with hypovitaminosis-C were at significantly higher risk of having a positive stool culture during the first 6 months of life (adjusted OR = 5.3, 95% CI 1.1; 26.1; P value = 0.038).

PMID:34137176 | DOI:10.1111/mcn.13215

Laboratory evaluation of the rapid diagnostic tests for the detection of Vibrio cholerae O1 using diarrheal samples

June 15, 2021

PLoS Negl Trop Dis. 2021 Jun 15;15(6):e0009521. doi: 10.1371/journal.pntd.0009521. Online ahead of print.

ABSTRACT

BACKGROUND: Cholera, an acute diarrheal disease is a major public health problem in many developing countries. Several rapid diagnostic tests (RDT) are available for the detection of cholera, but their efficacies are not compared in an endemic setting. In this study, we have compared the specificity and sensitivity of three RDT kits for the detection of Vibrio cholerae O1 and compared their efficiency with culture and polymerase chain reaction (PCR) methods.

METHODS: Five hundred six diarrheal stool samples collected from patients from two different hospitals in Kolkata, India were tested using SD Bioline Cholera, SMART-II Cholera O1 and Crystal-VC RDT kits. All the stool samples were screened for the presence of V. cholerae by direct and enrichment culture methods. Stool DNA-based PCR assay was made to target the cholera toxin (ctxAB) and O1 somatic antigen (rfb) encoding genes. Statistical evaluation of the RDTs has been made using STATA software with stool culture and PCR results as the gold standards. The Bayesian latent class model (LCM) was used to evaluate the diagnostic tests in the absence of the gold standard.

RESULTS: Involving culture technique as gold standard, the sensitivity and specificity of the cholera RDT kits in the direct testing of stools was highest with SAMRT-II (86.1%) and SD-Cholera (94.4%), respectively. The DNA based PCR assays gave very high sensitivity (98.4%) but the specificity was comparatively low (75.3%). After enrichment, the high sensitivity and specificity was detected with SAMRT-II (78.8%) and SD-Cholera (99.1%), respectively. Considering PCR as the gold standard, the sensitivity and specificity of the RDTs remained between 52.3-58.2% and 92.3-96.8%, respectively. In the LCM, the sensitivity of direct and enrichment testing was high in SAMRT-II (88% and 92%, respectively), but the specificity was high in SD cholera for both the methods (97% and 100%, respectively). The sensitivity/specificity of RDTs and direct culture have also been analyzed considering the age, gender and diarrheal disease severity of the patients.

CONCLUSION: Overall, the performance of the RDT kits remained almost similar in terms of specificity and sensitivity. Performance of PCR was superior to the antibody-based RDTs. The RTDs are very useful in identifying cholera cases during outbreak/epidemic situations and for making them as a point-of-care (POC) testing tool needs more improvement.

PMID:34129602 | DOI:10.1371/journal.pntd.0009521

Epidemic and PCR-based identification of vibrio cholera through OmpW gene from diarrhoeal patients admitted at different hospitals of Baluchistan

June 14, 2021

J Pak Med Assoc. 2021 Apr;71(4):1189-1192. doi: 10.47391/JPMA.1433.

ABSTRACT

OBJECTIVE: To study the different epidemiological and polymerase chain reaction-based identification of vibrio cholera.

METHODS: The cross-sectional study was conducted at the Center for Advanced Studies in Vaccinology and Biotechnology, University of Balochistan, Quetta, Pakistan, from January 5 to December 6, 2019, and comprised faecal / rectal swab samples from patients with a history of untreated severe diarrhoea of <12-hour duration. The samples were collected from suspected cholera patients at different hospitals of the province. The isolates were examined and identified on the basis of colony characters on thiosulfate-citrate-bile salts-sucrose agar. Susppected colonies were subjected to gram staining, biochemical tests and polymerase chain reaction-based identification. Data was analysed using SPSS 19.

RESULTS: Of the 444 samples, 33(7.43%) were positive for vibrio cholera and 411(92.56%) were negative. The incidence was higher in individuals aged 1-20 years 12(2.7%); males 18(4.05%); Balochs 18(4.05%); lower socioeconomic class 18(4.05%); and illiterates 26(5.85%). The incidence was more in summer 19(4.27%) and spring 8(1.80%) seasons. Polymerase chain reaction was highly effective diagnostic approach, with findings showing clear bands of 588bp of ompW gene.

CONCLUSIONS: Surveillance for diarrhoeal disorders is necessary to control future outbreaks of cholera in the region.

PMID:34125769 | DOI:10.47391/JPMA.1433

STRUGGLE AGAINST CHOLERA EPIDEMICS IN IMPERIAL TIME KHARKIV AS A SIGNIFICANT FACTOR OF PUBLIC HEALTH: HISTORICAL EXPERIENCE

June 5, 2021

Wiad Lek. 2021;74(5):1241-1244.

ABSTRACT

OBJECTIVE: The aim: The aim of the research is to determine and systematize administrative and medical measures aimed at curbing cholera in the city of Kharkiv in the time of the Russian Empire, to assess the relevance of the experience in fighting the disease, to determine the impact of epidemics and anti-epidemic measures on Kharkiv residents' public health.

PATIENTS AND METHODS: Materials and methods: General scientific and specific historical methods were used, and methods of related sciences were applied as well. The main methods of historical research included, in particular, historical analytical, chronological and comparative historical; methods of medical statistics, etc. The historiography of the issue was analyzed, unpublished archival materials, local press were studied.

CONCLUSION: Conclusions: Despite the progress made, mortality remained high in general, proving the public health system had to be reorganized. The death rate shocked the local community so much that the authorities had to apply an information blockade. Anti-epidemic components included explanatory work by priests and police, sanitary measures, measures on strict compliance with observation and quarantine, food supplies to the blocked city and free medicine dispensation, involvement of all available medical institutions, and the establishment of special temporary facilities, actual mobilization of medical personnel. It was impossible to act in the other way, because the treatment methods seemed to be ineffective, like today, under the COVID-19 pandemic. When the medical component is proved ineffective in fighting the epidemic, relatively effective administrative measures, tried and tested over the centuries reasonably seem to be useful, and this experience has not lost its relevance.

PMID:34090298

Epidemiology and genetic characterisation of human sapovirus among hospitalised acute diarrhoea patients in Bangladesh, 2012-2015

June 3, 2021

J Med Virol. 2021 Jun 3. doi: 10.1002/jmv.27125. Online ahead of print.

ABSTRACT

Human sapovirus, which causes acute gastroenteritis, is not well studied and poorly understood. This study aims to investigate the contribution of sapovirus in diarrhoea, their clinical association and genotypic diversity. Faecal specimens (n = 871) were randomly selected from diarrhoeal patients who attended icddr,b hospital in Dhaka, Bangladesh during January 2012 - December 2015 and tested for the presence of sapovirus RNA using real-time PCR. Sapovirus RNA was identified in 2.3% (n = 20) of the samples. Seventy-five percent of the sapovirus positive cases were co-infected with other pathogens; such as rotavirus, norovirus, ETEC, adenovirus, Shigella spp. and Vibrio Cholerae. A vast genetic diversity was observed among sapovirus with at least seven common genotypes (GI.1, GI.2, GI.7, GII.1, GII.4, GII.6, and GIV), and a new genotype GII.NA1. Some of the GI.1 strains detected were similar to GI.4 in the polymerase region sequence and were confirmed as recombinant strains. Our findings suggest that the overall contribution of sapovirus in hospitalized diarrhoeal illness is low but highlight enormous genetic diversity. This article is protected by copyright. All rights reserved.

PMID:34081341 | DOI:10.1002/jmv.27125

An Epidemiological Analysis of SARS-CoV-2 Genomic Sequences from Different Regions of India

June 2, 2021

Viruses. 2021 May 17;13(5):925. doi: 10.3390/v13050925.

ABSTRACT

The number of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) cases is increasing in India. This study looks upon the geographic distribution of the virus clades and variants circulating in different parts of India between January and August 2020. The NPS/OPS from representative positive cases from different states and union territories in India were collected every month through the VRDLs in the country and analyzed using next-generation sequencing. Epidemiological analysis of the 689 SARS-CoV-2 clinical samples revealed GH and GR to be the predominant clades circulating in different states in India. The northern part of India largely reported the 'GH' clade, whereas the southern part reported the 'GR', with a few exceptions. These sequences also revealed the presence of single independent mutations-E484Q and N440K-from Maharashtra (first observed in March 2020) and Southern Indian States (first observed in May 2020), respectively. Furthermore, this study indicates that the SARS-CoV-2 variant (VOC, VUI, variant of high consequence and double mutant) was not observed during the early phase of virus transmission (January-August). This increased number of variations observed within a short timeframe across the globe suggests virus evolution, which can be a step towards enhanced host adaptation.

PMID:34067745 | DOI:10.3390/v13050925

SARS-CoV-2 sero-prevalence among general population and healthcare workers in India, December 2020 - January 2021

May 22, 2021

Int J Infect Dis. 2021 May 19:S1201-9712(21)00442-2. doi: 10.1016/j.ijid.2021.05.040. Online ahead of print.

ABSTRACT

BACKGROUND: Earlier serosurveys in India revealed SARS-CoV-2 seroprevalence of 0.73% during May-June and 7.1% during August-September 2020. We conducted the third serosurvey during Dec 2020 and Jan 2021, to estimate the seroprevalence of SARS-CoV-2 infection among general population and healthcare workers (HCWs) in India.

METHODS: We conducted the serosurvey in the same 70 districts selected for the first and second serosurveys. From each district, we enrolled at least 400 individuals aged ≥ 10 years from general population and 100 HCWs from sub-district level health facilities. Sera from general population were tested for presence of IgG antibodies against nucleocapsid (N) and spike protein (S1-RBD) of SARS-CoV-2, whereas sera from HCWs were tested for anti-S1-RBD. We estimated weighted seroprevalence adjusted for assay characteristics.

RESULTS: Of the 28,598 sera from general population, 4585 (16%) had IgG antibodies against N, 6647 (23.2%) against S1-RBD and 7436 (26%) against either. The weighted and assay characteristic adjusted seroprevalence against either of the antibodies was 24.1 (95%CI: 23.0%-25.3%). Among 7385 HCWs, the seroprevalence of anti-S1-RBD IgG antibodies was 25.6% (95% CI: 23.5%-27.8%).

CONCLUSIONS: Nearly one in four individuals aged > = 10 years from general population as well as HCWs in India were exposed to SARS-CoV-2 by December 2020.

PMID:34022338 | DOI:10.1016/j.ijid.2021.05.040

Intranasal immunization with inactivated chlamydial elementary bodies formulated in VCG-chitosan nanoparticles induces robust immunity against intranasal Chlamydia psittaci challenge

May 18, 2021

Sci Rep. 2021 May 17;11(1):10389. doi: 10.1038/s41598-021-89940-8.

ABSTRACT

Vaccines based on live attenuated Chlamydia elementary bodies (EBs) can cause disease in vaccinated animals and the comparably safer inactivated whole EBs are only marginally protective. Recent studies show that a vaccine formulation comprising UV-inactivated EBs (EB) and appropriate mucosal delivery systems and/or adjuvants induced significant protective immunity. We tested the hypothesis that intranasal delivery of UV-inactivated C. psittaci EB formulated in Vibrio cholerae ghosts (VCG)-chitosan nanoparticles will induce protective immunity against intranasal challenge in SPF chickens. We first compared the impact of VCG and CpG adjuvants on protective immunity following IN mucosal and IM systemic delivery of EB formulated in chitosan hydrogel/microspheres. Immunologic analysis revealed that IN immunization in the presence of VCG induced higher levels of IFN-γ response than IM delivery or the CpG adjuvanted groups. Also, vaccine efficacy evaluation showed enhanced pharyngeal bacterial clearance and protection against lung lesions with the VCG adjuvanted vaccine formulation, thereby establishing the superior adjuvanticity of VCG over CpG. We next evaluated the impact of different concentrations of VCG on protective immunity following IN mucosal immunization. Interestingly, the adjuvanticity of VCG was concentration-dependent, since protective immunity induced following IN mucosal immunization showed dose-dependent immune responses and protection. These studies reveal that formulation of inactivated chlamydial antigens with adjuvants, such as VCG and chitosan increases their ability to induce protective immune responses against challenge.

PMID:34001988 | DOI:10.1038/s41598-021-89940-8

Influence of Community-Led Total Sanitation and Water Coverages in the Control of Cholera in Madarounfa, Niger (2018)

May 17, 2021

Front Public Health. 2021 Apr 29;9:643079. doi: 10.3389/fpubh.2021.643079. eCollection 2021.

ABSTRACT

Every year, cholera affects 1.3-4.0 million people worldwide with a particularly high presence in Africa. Based on recent studies, effective targeting interventions in hotspots could eliminate up to 50% of cases in Sub-Saharan Africa. Those interventions include Water, Sanitation, and Hygiene (WASH) programs whose influence on cholera control, up to the present, has been poorly quantified. Among the few studies available, D'Mello-Guyett et al. underline how the distribution of hygiene kits is a promising form of intervention for cholera control and that the integration of a WASH intervention at the point of admission of suspected cases is new in cholera control efforts, particularly in outbreaks and complex emergencies. Considering the limited number of studies on Community-Led Total Sanitation (CLTS) and water coverages related to cholera control, the aim of our work is to determine whether these interventions in cholera hotspots (geographic areas vulnerable to disease transmission) have significant impact on cholera transmission. In this study, we consider data collected on 125 villages of the Madarounfa district (Niger) during the 2018 cholera outbreak. Using a hurdle model, our findings show that full access to improved sanitation significantly decreases the likelihood of cholera by 91% (P < 0.0001) compared to villages with no access to sanitation at all. Considering only the villages affected by cholera in the studied area, cholera cases decrease by a factor of 4.3 in those villages where there is partial access to at least quality water sources, while full access to improved water sources decreases the cholera cases by a factor of 6.3 when compared to villages without access to water (P < 0.001). In addition, villages without access to safe water and sanitation are 6.7 times (P < 0.0001) more likely to get cholera. Alternatively, villages with full sanitation and water coverage are 9.1 (P < 0.0001) less likely to get cholera. The findings of our study suggest that significant access to improved water and sanitation at the village level offer a strong barrier against cholera transmission. However, it requires full CLTS coverage of the village to observe a strong impact on cholera, as partial access only has a limited impact.

PMID:33996720 | PMC:PMC8118121 | DOI:10.3389/fpubh.2021.643079

Regional Distribution of Causes of Death for Small Areas in Brazil, 1998-2017

May 14, 2021

Front Public Health. 2021 Apr 27;9:601980. doi: 10.3389/fpubh.2021.601980. eCollection 2021.

ABSTRACT

Background: What is the spatial pattern of mortality by cause and sex in Brazil? Even considering the main causes of death, such as neoplasms, cardiovascular diseases, external causes, respiratory diseases, and infectious diseases, there are still important debate regarding the spatial pattern of mortality by causes in Brazil. Evidence shows that there is an overlap in transitional health states, due to the persistence of infectious diseases (e.g., dengue, cholera, malaria, etc.,) in parallel with the increase in chronic degenerative diseases. The main objective of this paper is to analyze the spatio-temporal evolution of three groups of causes of death in Brazil across small areas from 1998 to 2017, by sex. Methods: We use publicly available data from the System Data Mortality Information (SIM-DATASUS) from 1998 to 2017. We focus on this period due to the better quality of information, in addition to all deaths are registered following the Tenth Revision of the International Classification of Diseases (ICD-10). We estimate standardized mortality rates by sex and cause aggregated into three main groups. We use a ternary color scheme to maximize all the information in a three-dimensional array of compositional data. Results: We find improvements in mortality from chronic degenerative diseases; faster declines are observed in the Southern regions of the country; but the persistence of high levels of mortality due to infectious diseases remained in the northern parts of the country. We also find impressive differences in external causes of deaths between males and females and an increase in mortality from these causes in the interior part of the country. Conclusions: This study provides useful information for policy makers in establishing effective measures for the prevention of deaths and public health planning for deaths from external and non-communicable causes. We observed how the distribution of causes of death varies across regions and how the patterns of mortality also vary by gender.

PMID:33987159 | PMC:PMC8111819 | DOI:10.3389/fpubh.2021.601980

Multidrug-resistant enteric pathogens in older children and adults with diarrhea in Bangladesh: epidemiology and risk factors

May 10, 2021

Trop Med Health. 2021 May 10;49(1):34. doi: 10.1186/s41182-021-00327-x.

ABSTRACT

BACKGROUND: Antimicrobial resistance (AMR) is a global public health threat and is increasingly prevalent among enteric pathogens in low- and middle-income countries (LMICs). However, the burden of multidrug-resistant organisms (MDROs) in older children, adults, and elderly patients with acute diarrhea in LMICs is poorly understood. This study's aim was to characterize the prevalence of MDR enteric pathogens isolated from patients with acute diarrhea in Dhaka, Bangladesh, and assess a wide range of risk factors associated with MDR.

METHODS: This study was a secondary analysis of data collected from children over 5 years, adults, and elderly patients with acute diarrhea at the International Centre for Diarrhoeal Disease Research, Bangladesh Dhaka Hospital between March 2019 and March 2020. Clinical, historical, socio-environmental information, and a stool sample for culture and antimicrobial susceptibility testing were collected from each patient. Univariate statistics and multiple logistic regression were used to assess the prevalence of MDR among enteric pathogens and the association between independent variables and presence of MRDOs among culture-positive patients.

RESULTS: A total of 1198 patients had pathogens isolated by stool culture with antimicrobial susceptibility results. Among culture-positive patients, the prevalence of MDR was 54.3%. The prevalence of MDR was highest in Aeromonas spp. (81.5%), followed by Campylobacter spp. (72.1%), Vibrio cholerae (28.1%), Shigella spp. (26.2%), and Salmonella spp. (5.2%). Factors associated with having MDRO in multiple logistic regression included longer transport time to hospital (>90 min), greater stool frequency, prior antibiotic use prior to hospital presentation, and non-flush toilet use. However, pseudo-R2 was low 0.086, indicating that other unmeasured variables need to be considered to build a more robust predictive model of MDR.

CONCLUSIONS: MDR enteric pathogens were common in this study population with clinical, historical, and socio-environmental risk factors associated with MDROs. These findings may help guide clinical decision-making regarding antibiotic use and selection in patients at greatest risk of complications due to MDROs. Further prospective research is urgently needed to determine what additional factors place patients at greatest risk of MDRO, and the best strategies to mitigate the spread of MDR in enteric pathogens.

PMID:33966631 | DOI:10.1186/s41182-021-00327-x

Memorials to John Snow - Pioneer in anaesthesia and epidemiology

May 7, 2021

J Med Biogr. 2021 May 7:9677720211013807. doi: 10.1177/09677720211013807. Online ahead of print.

ABSTRACT

John Snow was an English physician and a founding father of epidemiology, whose name is inextricably linked with tracing the source of the 1854 cholera outbreak in Soho, which killed over 600 people. Despite his recommendation to remove the water pump handle and thus reduce the spread of cholera, his theory of faecal-oral transmission was not widely believed until after his death. Furthermore, he also pioneered substantial achievements in the development of anaesthesia. He studied both chloroform and ether, improving the accuracy of their delivery. In his obstetric practice, he achieved the feat of obtaining satisfactory analgesia with a safer technique and is remembered for administering chloroform to Queen Victoria, during the delivery of her last two children. There are several interesting and unusual memorials to Snow, ranging from replica water pumps, blue plaques and a public house named after him. The most recent new memorial was erected in 2017, in his home town of York, which commemorates his origins and his subsequent contribution to curbing the cholera outbreak. All the memorials commemorate his achievements, which remain relevant today. Public health and epidemiology expertise is required in the current world of the COVID-19 pandemic, where his legacy remains as important as ever.

PMID:33960862 | DOI:10.1177/09677720211013807

The past and present of pandemic management: health diplomacy, international epidemiological surveillance, and COVID-19

April 30, 2021

Hist Philos Life Sci. 2021 Apr 30;43(2):64. doi: 10.1007/s40656-021-00416-4.

ABSTRACT

The establishment of international sanitary institutions, which took place in the context of rivalry among the great European powers and their colonial expansion in Asia, allowed for the development of administrative systems of international epidemiological surveillance as a response to the cholera epidemics at the end of the nineteenth century. In this note, I reflect on how a historical analysis of the inception of international epidemiological surveillance and pandemic management helps us to understand what is happening in the COVID-19 pandemic today.

PMID:33929621 | DOI:10.1007/s40656-021-00416-4

An outbreak of acute jaundice syndrome (AJS) among the Rohingya refugees in Cox's Bazar, Bangladesh: Findings from enhanced epidemiological surveillance

April 29, 2021

PLoS One. 2021 Apr 29;16(4):e0250505. doi: 10.1371/journal.pone.0250505. eCollection 2021.

ABSTRACT

In the summer of 2017, an estimated 745,000 Rohingya fled to Bangladesh in what has been described as one of the largest and fastest growing refugee crises in the world. Among numerous health concerns, an outbreak of acute jaundice syndrome (AJS) was detected by the disease surveillance system in early 2018 among the refugee population. This paper describes the investigation into the increase in AJS cases, the process and results of the investigation, which were strongly suggestive of a large outbreak due to hepatitis A virus (HAV). An enhanced serological investigation was conducted between 28 February to 26 March 2018 to determine the etiologies and risk factors associated with the outbreak. A total of 275 samples were collected from 18 health facilities reporting AJS cases. Blood samples were collected from all patients fulfilling the study specific case definition and inclusion criteria, and tested for antibody responses using enzyme-linked immunosorbent assay (ELISA). Out of the 275 samples, 206 were positive for one of the agents tested. The laboratory results confirmed multiple etiologies including 154 (56%) samples tested positive for hepatitis A, 1 (0.4%) positive for hepatitis E, 36 (13%) positive for hepatitis B, 25 (9%) positive for hepatitis C, and 14 (5%) positive for leptospirosis. Among all specimens tested 24 (9%) showed evidence of co-infections with multiple etiologies. Hepatitis A and E are commonly found in refugee camps and have similar clinical presentations. In the absence of robust testing capacity when the epidemic was identified through syndromic reporting, a particular concern was that of a hepatitis E outbreak, for which immunity tends to be limited, and which may be particularly severe among pregnant women. This report highlights the challenges of identifying causative agents in such settings and the resources required to do so. Results from the month-long enhanced investigation did not point out widespread hepatitis E virus (HEV) transmission, but instead strongly suggested a large-scale hepatitis A outbreak of milder consequences, and highlighted a number of other concomitant causes of AJS (acute hepatitis B, hepatitis C, Leptospirosis), albeit most likely at sporadic level. Results strengthen the need for further water and sanitation interventions and are a stark reminder of the risk of other epidemics transmitted through similar routes in such settings, particularly dysentery and cholera. It also highlights the need to ensure clinical management capacity for potentially chronic conditions in this vulnerable population.

PMID:33914782 | DOI:10.1371/journal.pone.0250505

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