Cholera Mortality Research Articles

Existence of cholera outbreak, challenges, and way forward on public health interventions to control cholera outbreak in Guraghe Zones, southern Ethiopia, 2023.

In Ethiopia, despite major improvements seen in health service delivery system, the country continues to be significantly affected by cholera outbreaks. Cholera remains a significant public health problem among the vulnerable populations living in many resource-limited settings with poor access to safe and clean water and hygiene practices. Recurring cholera outbreaks are an indication of deprived water and sanitation conditions as well as weak health systems, contributing to the transmission and spread of the cholera infection. To assess the cholera outbreak, its challenges, and the way forward on public health interventions to solve the knowledge and health service delivery gaps related to cholera control in Guraghe Zone, Ethiopia, 2023. Active surveillance of the cholera outbreak was conducted in all kebeles and town administrative of Guraghe zone from 7/8/2023 to 30/10/2023. A total of 224 cholera cases were detected during the active surveillance method. Data obtained from Guraghe zone offices were exported to SPSS version 25 for additional analysis. The case fatality rate, incidence of the cases, and other descriptive variables were presented and described using figures and tables. A total of 224 cholera cases were detected through an active surveillance system. In this study, the case fatality rate of cholera outbreak was 2.6%. To tackle the cholera outbreak, the Guraghe zone health office collaborated with other stakeholders to prepare four cholera treatment centers. The absence of OCV, inaccessible safe water, low latrine coverage, inappropriate utilization of latrines, and absence of cholera laboratory rapid diagnostics test in Guraghe Zone are barriers to tackling the outbreak. Ethiopia National Cholera Plan targeted eradicating cholera by 2030, 222 cholera outbreak occurred in Guraghe Zone, Ethiopia. To minimize and control cholera mortality rate oral cholera vaccinations should be employed in all areas of the region. Sustainable WASH measures should be guaranteed for the use of safe water and good hygiene practices. Early diagnosis and treatment should be initiated appropriately for those who are infected.

The surging cholera epidemic in Africa: a review of the current epidemiology, challenges and strategies for control

Africa, a known region with abundant warm coastal waters and a natural reservoir for Vibrio cholera, is known to bear the highest burden of cholera morbidity and mortality globally. Malawi is currently experiencing the deadliest cholera outbreak in two decades, and neighbouring countries, Mozambique and Zambia, have also reported significant numbers of cases. If the current trend of cholera transmission is sustained, the number of fatalities recorded in 2021, Africa’s deadliest year for cholera over the past decade, might be exceeded. This article aims to review the current epidemiology, prevention and control strategies, and treatment of cholera in Africa to highlight context-specific challenges and recommend possible solutions. The authors found out that cholera outbreaks in Africa are taking place in the midst of epidemics (measles, mumps, etc.) and natural disasters like cyclones and flooding (Mozambique, Malawi), drought (Kenya, and Ethiopia), and conflict (Cameroon, the DR Congo, Nigeria, and Ethiopia). The shortages of medical supplies like cholera kits and oral cholera vaccines in many countries due to constrained and limited resources and antibiotic resistance further make management and control difficult. The outbreak is spreading throughout the region because of poor sanitation, unsafe water supplies, and increased cross-border travel. Cholera in Africa follows a seasonal pattern, suggesting specific periods for heightened outbreak preparedness and response. The authors suggest a targeted multisectorial approach and a coordinated mechanism to respond to the epidemic through sustained political will, formidable partnerships, resource mobilisation, and the provision of technical support and advocacy at sub-national, national, and international levels.

Cholera Deaths During Outbreaks in Uvira, Eastern Democratic Republic of the Congo, 10-35 Months After Mass Vaccination.

Our understanding of the burden and drivers of cholera mortality is hampered by limited surveillance and confirmation capacity. Leveraging enhanced clinical and laboratory surveillance in the cholera-endemic community of Uvira, eastern Democratic Republic of Congo, we describe cholera deaths across 3 epidemics between September 2021 and September 2023 following mass vaccination.

Evaluation of Utilization Practices towards Cholera Response Water Tanks among Residents: A Case Study of Lusaka District.

Cholera outbreaks generally occur when water, sanitation and hygiene (WASH) services are inadequate or compromised. Annual estimates stand at 2.9 million cases and 95,000 deaths across 69 cholera-endemic countries with Sub-Saharan Africa and South Asia leading on the global cholera morbidity and mortality rates. Zambia continues to report higher morbidity and mortality with each recurrent outbreak. This raises concern on the impact of available interventions. This study was cross-sectional and employed qualitative evaluative techniques. Thirty (30) Focus Group Discussions (FGDs) supplemented with field notes by researchers) were conducted with 14 participants in each group drawn from 2 epi-centers i.e. Matero and Kanyama Sub-districts which accounted for over 70% of mortalities and morbidities. These epi-centers received 107 water tanks from authorities. The study found that residents were aware of the outbreak and attributed it to hygiene standards in the community while citing poor waste management and unsafe drinking water sources. The study also found poor WASH practices which included inability to perform correct hand hygiene during water collection, use of uncovered buckets and allowing children at the water points. Residents accessed the cholera response tanks and appreciated the intervention the government had put in place. Among the uses of the water from the tanks, residents preferred the water from cholera response tanks as they noted it tasted like mineral water. However, the water was prominently used for bathing highlighting that it made their skin smooth. The study also noted erratic supply as tanks ran out of water within 24hrs and it took an average of 4 days to refill the tanks. The study concluded that this intervention was appreciated, however, due to poor hygiene standards and erratic supply of water, the intended result could not be realized. The study recommends long term solutions such as drilling of boreholes alongside the tanks as well as repairing existing supply networks to water kiosks with consistency in water supply by utility companies.

Global Patterns of Trends in Cholera Mortality.

Cholera is a large public health issue, especially in countries with limited resources. The aim of the study was to determine trends in global cholera mortality from 1990-2019. This research is an observational, descriptive epidemiological study. The age-standardized rates (ASRs, per 100,000 population) of cholera mortality from 1990 to 2019 were evaluated through joinpoint regression analysis (by calculating Odds Ratio-OR, with corresponding 95% Confidence Interval-95% CI). From 1990-2019 in the world, the number of deaths due to cholera in both sexes together increased, ranging from 83,045 in 1990 to 117,167 in 2019. During the observed period, there were about 3.0 million deaths due to cholera in the world. In both sexes together in 2019, the cholera mortality rate was the highest in Nigeria (ARS = 39.19) and Central African Republic (ARS = 38.80), followed by populations in Eritrea (ARS = 17.62) and Botswana (ARS = 13.77). Globally, cholera-related mortality significantly decreased in males (AAPC = -0.4%, 95% CI = -0.7 to -0.1), while a stable trend was noted in females (AAPC = -0.1%, 95% CI = -0.4 to 0.2) in the observed period. In the African Region, significantly increasing cholera-related mortality trends were observed both in males and females (AAPC = 1.3% and AAPC = 1.1%, respectively). Cholera mortality showed a constantly increasing trend in the African Region over the last three decades. More efforts in cholera management are necessary for effective response to the growing mortality in developing countries.

Rising cases of cholera in Ethiopia: a need for sustainable wash practices?

Rising cases of cholera in Ethiopia: a need for sustainable wash practices?

Exploring the effects of weaning age on adult infectious disease mortality among 18th-19th century Italians.

The developmental origins of health and disease (DOHaD) hypothesis describes how early childhood stress affects morbidity and mortality later in life. The role of early childhood stress in mortality from infectious disease is understudied. Stressors in early childhood that weaken the immune system may result in increased susceptibility to infectious disease in adulthood. Weaning is one of the earliest potential periods of significant stress in early childhood. This research investigates the effect of weaning after ~6months of age on cholera mortality among 18th-19th-century Italian populations by determining if earlier breastfeeding cessation is associated with earlier mortality, analyzing childhood dietary variation and physiological stress markers, and determining if age-at-weaning completion differs between catastrophic and attritional populations. Serial dentin stable carbon and nitrogen isotope analyses from canines are compared between catastrophic (n=45) and attritional groups (n=23). Canines are sectioned serially from crown to apex, and the increment's δ15 N and δ13 C are used to estimate age-at-weaning completion. Catastrophic and attritional groups exhibit similar age-at-weaning completion (~2.8 years). Seventy-four percent of individuals lack elevated δ15 N values in dentin that formed during infancy. Age-at-weaning completion was not a predisposing factor in cholera mortality in adulthood in this sample. Age-at-weaning completion may not be significantly associated with infectious disease mortality because weaning completion likely occurred after infants had adapted to consuming contaminated weanling foods. Individuals without detectable weaning curves may represent infants who received supplementary foods since birth or were weaned before the age of 6-9months.

Cholera outbreaks in sub-Saharan Africa during 2010-2019: a descriptive analysis

BackgroundCholera remains a public health threat but is inequitably distributed across sub-Saharan Africa. Lack of standardized reporting and inconsistent outbreak definitions limit our understanding of cholera outbreak epidemiology. MethodsFrom a database of cholera incidence and mortality, we extracted data from sub-Saharan Africa and reconstructed outbreaks of suspected cholera starting in January 2010 to December 2019 based on location-specific average weekly incidence rate thresholds. We then described the distribution of key outbreak metrics. ResultsWe identified 999 suspected cholera outbreaks in 744 regions across 25 sub-Saharan African countries. The outbreak periods accounted for 1.8 billion person-months (2% of the total during this period) from January 2010 to January 2020. Among 692 outbreaks reported from second-level administrative units (e.g., districts), the median attack rate was 0.8 per 1000 people (interquartile range (IQR), 0.3-2.4 per 1000), the median epidemic duration was 13 weeks (IQR, 8-19), and the median early outbreak reproductive number was 1.8 (range, 1.1-3.5). Larger attack rates were associated with longer times to outbreak peak, longer epidemic durations, and lower case fatality risks. ConclusionsThis study provides a baseline from which the progress toward cholera control and essential statistics to inform outbreak management in sub-Saharan Africa can be monitored.

Putting rapid tests to work in surveillance and control of cholera

The Global Taskforce for Cholera Control (GTFCC) End Cholera Roadmap encourages countries with endemic and epidemic cholera transmission to identify cholera hotspots in order to prioritize multi-sectoral prevention and control strategies, including oral cholera vaccines and water/sanitation infrastructure [1]. Although cholera is inextricably linked to poverty, including limited access to safe water and sanitation, there is limited predictive value in common metrics related to these for identifying where cholera incidence or mortality risk is high.

Spatial comparison of herald and main waves in London's nineteenth-century cholera epidemics.

Nineteenth-century London experienced four extraordinarily severe summertime cholera epidemics. Three were preceded by less severe non-summer outbreaks. Twenty-first-century research hypothesizes them as herald waves of potentially new cholera strains. This study examined the geographical characteristics of these herald waves and compared them to their subsequent main waves to determine if there was a geographical component to the significant difference in wave severity. Cholera mortality data for London's parishes and registration districts were extracted from contemporaneous records. The data were normalized and scaled. Each epidemic wave was divided into two segments for analysis. A Spearman's rank correlation was used to assess the relationship between a herald and its subsequent main wave. Geospatial analytical tools were used to determine and display each segment's geographic distribution pattern using autocorrelation techniques to determine its central point. Results show that the herald wave of each epidemic shared characteristics similar to its following main wave. Central-point locations were similar and Spearman's rank coefficients showed high degrees of correlation. Autocorrelation results were similar, with one exception reflecting an appalling anomalous cholera outbreak at an institution for children. Because of the demonstrated similarity of each epidemic's herald and main waves, this study did not detect a spatial characteristic that could explain the observed difference in severity between the studied heralds and mains.

The adverse health effects associated with drought in Africa

Droughts are associated with several health effects and Africa is uniquely vulnerable. Despite this, there has been no previous review of the literature on the health effects of drought in Africa. This study systematically reviewed the epidemiological research on the association between drought and adverse health effects in Africa (2012–2019). A total of fifteen articles were included in the review after screening 1922 published (peer-reviewed) and unpublished articles. These studies were all conducted in 9 Sub-Saharan African countries. The drought-related health effects identified were on adverse nutritional health (n = 8) including malnutrition resulting in reduced body size and wasting, stunting and underweight, mortality from food insecurity, anaemia from food insecurity and nutrition-related disability from food insecurity; drought and diseases due to microbial contamination of water (n = 6) including cholera, diarrhoeal diseases, scabies, vector-borne diseases and malaria-related mortality; and drought and health behaviours (n = 1) including HIV prevention and care behaviours. The study found limited evidence of a high prevalence of malnutrition, an increased prevalence of anaemia, cholera, scabies, dengue and an increased incidence in child disabilities during periods of drought. Additionally, there was limited evidence on improved child nutritional health with improved water and sanitation access, and an increased prevalence of child wasting, stunting and underweight in drought-prone areas. No evidence of drought on other health outcomes was found. However, all the studies had more than one limitation including weak study design, a lack of comparison to a drought period, uncertainty on the onset and end of drought, lack of control for confounding, presence of contextual factors, weak outcome and/or exposure measure, small sample size and lack of generalizability.This review found weak evidence for all health outcomes measured but highlights key areas for further research and contextual factors which need to be considered for interventions.

Novel multi-strain probiotics reduces Pasteurella multocida induced fowl cholera mortality in broilers

Pasteurella multocida causes fowl cholera, a highly contagious poultry disease of global concern, causing significant ecological and economic challenges to the poultry industry each year. This study evaluated the effects of novel multi-strain probiotics consisting of Lactobacillus plantarum, L. fermentum, Pediococcus acidilactici, Enterococcus faecium and Saccharomyces cerevisiae on growth performance, intestinal microbiota, haemato-biochemical parameters and anti-inflammatory properties on broilers experimentally challenged with P. multocida. A total of 120 birds were fed with a basal diet supplemented with probiotics (108 CFU/kg) and then orally challenged with 108 CFU/mL of P. multocida. Probiotics supplementation significantly (P < 0.05) improved growth performance and feed efficiency as well as reducing (P < 0.05) the population of intestinal P. multocida, enterobacteria, and mortality. Haemato-biochemical parameters including total cholesterol, white blood cells (WBC), proteins, glucose, packed cell volume (PCV) and lymphocytes improved (P < 0.05) among probiotic fed birds when compared with the controls. Transcriptional profiles of anti-inflammatory genes including hypoxia inducible factor 1 alpha (HIF1A), tumor necrosis factor- (TNF) stimulated gene-6 (TSG-6) and prostaglandin E receptor 2 (PTGER2) in the intestinal mucosa were upregulated (P < 0.05) in probiotics fed birds. The dietary inclusion of the novel multi-strain probiotics improves growth performance, feed efficiency and intestinal health while attenuating inflammatory reaction, clinical signs and mortality associated with P. multocida infection in broilers.

Optimal Control Analysis of Cholera Dynamics in the Presence of Asymptotic Transmission

Many mathematical models have explored the dynamics of cholera but none have been used to predict the optimal strategies of the three control interventions (the use of hygiene promotion and social mobilization; the use of treatment by drug/oral re-hydration solution; and the use of safe water, hygiene, and sanitation). The goal here is to develop (deterministic and stochastic) mathematical models of cholera transmission and control dynamics, with the aim of investigating the effect of the three control interventions against cholera transmission in order to find optimal control strategies. The reproduction number Rp was obtained through the next generation matrix method and sensitivity and elasticity analysis were performed. The global stability of the equilibrium was obtained using the Lyapunov functional. Optimal control theory was applied to investigate the optimal control strategies for controlling the spread of cholera using the combination of control interventions. The Pontryagin’s maximum principle was used to characterize the optimal levels of combined control interventions. The models were validated using numerical experiments and sensitivity analysis was done. Optimal control theory showed that the combinations of the control intervention influenced disease progression. The characterisation of the optimal levels of the multiple control interventions showed the means for minimizing cholera transmission, mortality, and morbidity in finite time. The numerical experiments showed that there are fluctuations and noise due to its dependence on the corresponding population size and that the optimal control strategies to effectively control cholera transmission, mortality, and morbidity was through the combinations of all three control interventions. The developed models achieved the reduction, control, and/or elimination of cholera through incorporating multiple control interventions.

ТАЮЩАЯ РОСКОШЬ : ЛЕД В КОЛОНИАЛЬНЫХ ТРОПИКАХ

The article examines the problems of corporeality and materiality in the colonial context of British India in the 19 th - early 20 th centuries. The orientalist idea of the asymmetry of the bodies of the colonialists and the colonized ones emphasized the physical superiority of the former in relation to the latter and served as one of the justifications for the legitimacy of foreign power in the Indian subcontinent. This made the comfort and physical well-being of the British in the colony not only their personal need, but also part of the public order of things. However, according to colonial narratives, finding themselves in difficult temperature conditions, the British suffered from migraines, dizziness, heat stroke, prickly heat, lichen, insect bites, classic tropical diseases - fever / malaria, cholera, dysentery, and high mortality. As a result, they became the object of care and control from the state, subordinating their bodies to its goals, namely, the need to be healthy, strong, vigorous, beautiful to maintain a decent image and viable to exercise power in unusual climatic conditions. The focus is on ways to bring tropically traumatized British bodies to a state of physical norm, in particular cooling and ice-making technologies. Ice in a hot climate was not a natural phenomenon, but a technological product that required the mobilization of large finances and manpower, sophisticated marketing policies, as well as complex infrastructure and technical innovations. Thus, ice became a visual marker not only of the wealth of foreign rulers, but also of their belonging to the culture of modernity with its characteristic internationalization of commercial, economic and intellectual ties.

John Snow, Cholera, and South London Reconsidered

John Snow, the London doctor often considered the father of modern epidemiology, analyzed 1849 and 1854 cholera mortality for a population of nearly half a million in South London. His aim was to convince skeptics and “prove the overwhelming influence which the nature of the water supply exerted over the Snow's analysis was innovative - he is commonly credited with the first application of both randomization as an instrumental variable and differences-in-differences (DiD). This paper provides an historical review of Snow's three approaches to analyzing the data: a direct comparison of mixed (quasi-randomized) populations; a primitive form of difference-in-differences; and a comparison of actual versus predicted mortality. Snow's analysis did not convince his skeptics, and we highlight problems with his analysis. We then turn to a re-analysis of Snow's evidence, casting his analysis in the modern forms of randomization as IV and DiD. The re-examination supports Snow's claims that data demonstrated the influence of water supply. As a matter of historical interest this strengthens the argument against Snow's skeptics. For modern practitioners, the data and analysis provide an example of modern statistical tools (randomization and DiD) and the complementary use of observational and (quasi) experimental data.

Choleraepidemien in den Städten der österreichischen Alpenländer in den 1830er Jahren

In 1831 the first European cholera epidemic hit most parts of Lower Austria hard. The traditional system of fighting plague epidemics based on advance warning, cordons sanitaire and quarantine proved to be ineffective in the case of cholera. Shocked by the sudden death of many cholera victims the imperial government tried to push forward investments in sewers and the water supply at least in the capital Vienna. Unfortunately these investments showed no improving effect on cholera morbidity and mortality in the 1830s, because the quality of filtered water from the river Danube that supplied the Kaiser-Ferdinand-Wasserleitung build in 1836-1843 was inadequate and the new sewer-system, the so called Cholera-sewers, lacked functional capability in summer and during floods. Due to the fact that most of the cholera epidemics entered the Habsburg monarchy from the east or from the Adriatic sea, the inner Alpine provinces with the exception of South Tyrol remained almost untouched by cholera epidemics of that era. The east-west-gradient in mortality cannot be explained by any measures to improve the water supply or sewer system in these parts of Austria. Most households in cities of these provinces were supplied with drinking water by domestic wells and sanitation was dominated by cesspools, which was the case even in most parts of Vienna. What might explain the difference in mortality is the lower population density correlated with the better quality of water from the wells in the Alpine zone.

Difference-in-Difference in the Time of Cholera: a Gentle Introduction for Epidemiologists.

The goal of this article is to provide an introduction to the intuition behind the difference-in-difference method for epidemiologists. We focus on the theoretical aspects of this tool, including the types of questions for which difference-in-difference is appropriate, and what assumptions must hold for the results to be causally interpretable. While currently under-utilized in epidemiologic research, the difference-in-difference method is a useful tool to examine effects of population-level exposures, but relies on strong assumptions. We use the famous example of John Snow's investigation of the cause of cholera mortality in London to illustrate the difference-in-difference approach and corresponding assumptions. We conclude by arguing that this method deserves a second-look from epidemiologists interested in asking causal questions about the impact of a population-level exposure change on a population-level outcome for the group that experienced the change.

The Effect of Water Filtration on Cholera Mortality

There is debate among researchers regarding the importance of water filtration in reducing mortality during the epidemiological transition. However, there is limited research on how water filtration affected cholera mortality during the second half of the 19th century. Using historical micro-data, this paper provides new evidence on the importance of water filtration in reducing cholera mortality during an outbreak. The results show that access to filtered water protected almost completely against cholera mortality. Water filtration could thereby have contributed more to mortality decline than what has previously been documented.

Risk and Protective Factors for Cholera Deaths during an Urban Outbreak-Lusaka, Zambia, 2017-2018.

The Republic of Zambia declared a cholera outbreak in Lusaka, the capital, on October 6, 2017. By mid-December, 20 of 661 reported cases had died (case fatality rate 3%), prompting the CDC and the Zambian Ministry of Health through the Zambia National Public Health Institute to investigate risk factors for cholera mortality. We conducted a study of cases (cholera deaths from October 2017 to January 2018) matched by age-group and onset date to controls (persons admitted to a cholera treatment center [CTC] and discharged alive). A questionnaire was administered to each survivor (or relative) and to a family member of each decedent. We used univariable exact conditional logistic regression to calculate matched odds ratios (mORs) and 95% CIs. In the analysis, 38 decedents and 76 survivors were included. Median ages for decedents and survivors were 38 (range: 0.5-95) and 25 (range: 1-82) years, respectively. Patients aged > 55 years and those who did not complete primary school had higher odds of being decedents (matched odds ratio [mOR] 6.3, 95% CI: 1.2-63.0, P = 0.03; mOR 8.6, 95% CI: 1.8-81.7, P < 0.01, respectively). Patients who received immediate oral rehydration solution (ORS) at the CTC had lower odds of dying than those who did not receive immediate ORS (mOR 0.1, 95% CI: 0.0-0.6, P = 0.02). Cholera prevention and outbreak response should include efforts focused on ensuring access to timely, appropriate care for older adults and less educated populations at home and in health facilities.

Contemporary Nigerian public health problem: prevention and surveillance are key to combating cholera.

Cholera is a public health problem around the world, and it is endemic in Africa, parts of Asia, the Middle East as well as South and Central America. This review characterizes an cholera outbreak in Nigeria in 2017/2018. On the basis of own experiences and the analysis of historical outbreaks, the Vibrio cholera strains, mode of transmission, signs and symptoms, and most important the prevention and control measures are identified. Untreated, the lethality of cholera is up to 70%. Therefore, a multifaceted approach including public policy, surveillance, water purification and hygiene, community sensitization, and the use of oral cholera vaccination (OVC) is vital to prevent, control, and reduce the cholera mortality rate. It is recommended that the government pass legislation to implement preventive and surveillance measures, e.g., invest in drinking water systems, sanitation systems and sewage treatment, and promote public education on basic hygiene. The latter includes boiling and treating water before drinking, washing hands frequently with soap and clean water, thoroughly cooking food before consumption, avoiding open defecation, disposing of wastes properly, and immediately taking anyone with signs and symptoms of cholera such as watery diarrhea to the hospital for treatment.