Drought-related cholera outbreaks in Africa and the implications for climate change: a narrative review

Existing Challenges and Opportunities for Advancing Drought and Health Research

PURPOSE OF REVIEW

Drought is one of the most far-reaching natural disasters, yet drought and health research is sparse. This may be attributed to the challenge of quantifying drought exposure, something complicated by multiple drought indices without any designed for health research. The purpose of this general review is to evaluate current drought and health literature and highlight challenges or scientific considerations when performing drought exposure and health assessments.

RECENT FINDINGS

The literature revealed a small, but growing, number of drought and health studies primarily emphasizing Australian, western European, and US populations. The selection of drought indices and definitions of drought are inconsistent. Rural and agricultural populations have been identified as vulnerable cohorts, particularly for mental health outcomes. Using relevant examples, we discuss the importance of characterizing drought and explore why health outcomes, populations of interest, and compound environmental hazards are crucial considerations for drought and health assessments. As climate and health research is prioritized, we propose guidance for investigators performing drought-focused analyses.

Climate change and healthy ageing: An assessment of the impact of climate hazards on older people

Background

Climate change not only directly impacts older people's longevity but also healthy ageing, which is the process of maintaining physical and mental capacities while optimising functional abilities. The urgency to address both population ageing and climate change necessitates a rethink and assessment of the impact of climate change on older people. This includes identifying what can be done to anticipate, mitigate and adapt to climate change and engage older persons.

Methods

A review of climate change and healthy ageing forms the basis of evidence in this report. We developed a comprehensive search to assess current literature, combining terms related to ageing and climate change across four major data sets and assessing articles published up to the end of 2021.

Results

We summarised the current and future impact of climate change on older people and developed a framework identifying climate change impacts on older persons, recognising social and environmental determinants of healthy ageing. Major hazards and some key exposure pathways include extreme temperatures, wildfire, drought, flooding, storm and sea level rise, air quality, climate-sensitive infectious diseases, food and water insecurities, health and social care system displacement, migration, and relocation. Strategies to address climate change require interventions to improve systems and infrastructure to reduce vulnerability and increase resilience. As a heterogeneous group, older people's perceptions of climate change should be integrated into climate activism. Increasing climate change literacy among older people and enabling them to promote intergenerational dialogue will drive the development and implementation of equitable solutions. Pathways may operate via direct or indirect exposures, requiring longitudinal studies that enable assessment of exposures and outcomes at multiple time points, and analyses of cumulative impacts of hazards across the life course.

Conclusions

The lack of systematic reviews and primary research on the impact of most climate hazards, except for heat, on older people is apparent. Future research should include outcomes beyond mortality and morbidity and assess how older people interact with their environment by focusing on their capacities and optimising abilities for being and doing what they value.

Analysis of environmental factors influencing endemic cholera risks in sub-Saharan Africa

The recurring cholera outbreaks in sub-Saharan Africa are of growing concern, especially considering the potential acceleration in the global trend of larger and more lethal cholera outbreaks due to the impacts of climate change. However, there is a scarcity of evidence-based research addressing the environmental and infrastructure factors that sustain cholera recurrence in Africa. This study adopts a statistical approach to investigate over two decades of endemic cholera outbreaks and their relationship with five environmental factors: water provision, sanitation provision, raising temperatures, increased rainfall and GDP. The analysis covers thirteen of the forty-two countries in the mainland sub-Saharan region, collectively representing one-third of the region's territory and half of its population. This breadth enables the findings to be generalised at a regional level. Results from all analyses consistently associate water provision with cholera reduction. The stratified model links increased water provision with a reduction in cholera risk that ranged from 4.2 % to 84.1 % among eight countries (out of 13 countries) as well as a reduction of such risk that ranged from 9.8 % to 68.9 % when there is increased sanitation provision, which was observed in nine countries (out of 13). These results indicate that the population's limited access to water and sanitation, as well as the rise in temperatures, are critical infrastructure and environmental factors contributing to endemic cholera and the heightened risk of outbreaks across the sub-Saharan region. Therefore, these are key areas for targeted interventions and cross-border collaboration to enhance resilience to outbreaks and lead to the end of endemic cholera in the region. However, it is important to interpret the results of this study with caution; hence, further investigation is recommended to conduct a more detailed analysis of the impact of infrastructure and environmental factors on reducing cholera risk.

Cholera rages in Africa and the Middle East: A narrative review on challenges and solutions

Background and Aim

Cholera is a life-threatening infectious disease that is still one of the most common acute watery diarrheal diseases in the world today. Acute diarrhea and severe dehydration brought on by cholera can cause hypovolemic shock, which can be fatal in minutes. Without competent clinical therapy, the rate of case fatality surpasses 50%. The purpose of this review was to highlight cholera challenges in Africa and the Middle East and explain the reasons for why this region is currently a fertile environment for cholera. We investigated cholera serology, epidemiology, and the geographical distribution of cholera in Africa and the Middle East in 2022 and 2023. We reviewed detection methods, such as rapid diagnostic tests (RDTs), and treatments, such as antibiotics and phage therapy. Finally, this review explored oral cholera vaccines (OCVs), and the vaccine shortage crisis.

Methods

We carried out a systematic search in multiple databases, including PubMed, Web of Science, Google Scholar, Scopus, MEDLINE, and Embase, for studies on cholera using the following keywords: ((Cholera) OR (Vibrio cholera) and (Coronavirus) OR (COVID-19) OR (SARS-CoV2) OR (The Middle East) OR (Africa)).

Results and Conclusions

Cholera outbreaks have increased dramatically, mainly in Africa and many Middle Eastern countries. The COVID-19 pandemic has reduced the attention devoted to cholera and disrupted diagnosis and treatment services, as well as vaccination initiatives. Most of the cholera cases in Africa and the Middle East were reported in Malawi and Syria, respectively, in 2022. RDTs are effective in the early detection of cholera epidemics, especially with limited advanced resources, which is the case in much of Africa. By offering both direct and indirect protection, expanding the use of OCV will significantly reduce the burden of current cholera outbreaks in Africa and the Middle East.

Climate change, biodiversity loss, and Indigenous Peoples' health and wellbeing: A systematic umbrella review

Indigenous Peoples worldwide are experiencing a cascade of impacts on their health and wellbeing as a result of climate change and biodiversity loss. Existing literature at the interface of climate change, biodiversity loss, and Indigenous health tells us that Indigenous Peoples are among those most disproportionately and acutely affected by these impacts. Yet, a gap exists with respect to comprehensively and critically synthesizing the impacts reported across this literature and identifying Indigenous-led responses. Guided by an Indigenous advisory group, we employed a systematic umbrella review methodology, following PRISMA guidelines, to characterize the global secondary literature (PROSPERO registration #: CRD42023417060). In so doing, we identified the proximal, intermediate, distal, and gendered impacts of climate change and biodiversity loss on Indigenous health and wellbeing as well as Indigenous-led responses. Five databases were searched for published reviews, along with a grey literature search that focused on underrepresented geographic regions in the academic literature. Two independent reviewers conducted two-stage screening, data extraction, and quality assessment of retrieved records. Basic descriptive statistics were calculated. Qualitative data were analyzed thematically, using a constant comparative approach. A total of 38 review articles met the eligibility criteria and 37 grey literature records were retrieved and included in the review. Reviews were published between 2010-2023 and geographically clustered in the Circumpolar North. Intersecting proximal, intermediate, and distal impacts were characterized as place-based and specific, and linked to colonialism as an antecedent to and driver of these impacts. Gendered impacts were underexplored within reviews. Reviewed literature underscored the value of engaging diverse knowledge systems; platforming localized, community-led adaptation to climate change and biodiversity loss, while addressing sociopolitical constraints to these efforts; and applying a broader conceptualization of health that aligns with Indigenous frameworks. Going forward, we must foreground equity- and rights-based considerations within integrated responses to climate and biodiversity crises.

Sporadic regional re-emergent cholera: a 19th century problem in the 21st century

Cholera, caused by Vibrio cholerae, is a severe diarrheal disease that necessitates prompt diagnosis and effective treatment. This review comprehensively examines various diagnostic methods, from traditional microscopy and culture to advanced nucleic acid testing like polymerase spiral reaction and rapid diagnostic tests, highlighting their advantages and limitations. Additionally, we explore evolving treatment strategies, with a focus on the challenges posed by antibiotic resistance due to the activation of the SOS response pathway in V. cholerae. We discuss promising alternative treatments, including low-pressure plasma sterilization, bacteriophages, and selenium nanoparticles. The paper emphasizes the importance of multidisciplinary approaches combining novel diagnostics and treatments in managing and preventing cholera, a persistent global health challenge. The current re-emergent 7th pandemic of cholera commenced in 1961 and shows no signs of abeyance. This is probably due to the changing genetic profile of V. cholerae concerning bacterial pathogenic toxins. Given this factor, we argue that the disease is effectively re-emergent, particularly in Eastern Mediterranean countries such as Lebanon, Syria, etc. This review considers the history of the current pandemic, the genetics of the causal agent, and current treatment regimes. In conclusion, cholera remains a significant global health challenge that requires prompt diagnosis and effective treatment. Understanding the history, genetics, and current treatments is crucial in effectively addressing this persistent and re-emergent disease.

The relationship between climate change, globalization and non-communicable diseases in Africa: A systematic review

Climate change and non-communicable diseases (NCDs) are considered the 21st Century's major health and development challenges. Both pose a disproportionate burden on low- and middle-income countries that are unprepared to cope with their synergistic effects. These two challenges pose risks for achieving many of the sustainable development goals (SDGs) and are both impacted by globalization through different pathways. While there are important insights on how climate change and or globalization impact NCDs in the general literature, comprehensive research that explores the influence of climate change and or globalization on NCDs is limited, particularly in the context of Africa. This review documents the pathways through which climate change and or globalization influence NCDs in Africa. We conducted a comprehensive literature search in eight electronic databases-Web of Science, PubMed, Scopus, Global Health Library, Science Direct, Medline, ProQuest, and Google Scholar. A total of 13864 studies were identified. Studies that were identified from more than one of the databases were automatically removed as duplicates (n = 9649). Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a total of 27 studies were eventually included in the final review. We found that the impacts of climate change and or globalization on NCDs act through three potential pathways: reduction in food production and nutrition, urbanization and transformation of food systems. Our review contributes to the existing literature by providing insights into the impact of climate change and or globalization on human health. We believe that our findings will help enlighten policy makers working on these pathways to facilitate the development of effective policy and public health interventions to mitigate the effects of climate change and globalization on the rising burden of NCDs and goal 3 of the SDG, in particular.

Vibrio species: development of EUCAST susceptibility testing methods and MIC and zone diameter distributions on which to determine clinical breakpoints

OBJECTIVES

Most human infections caused by Vibrio spp. do not warrant antimicrobial treatment but in severe cases, targeted antimicrobial treatment can be lifesaving. For Vibrio spp., standardized antimicrobial susceptibility testing (AST) guidelines with EUCAST methodology are lacking. In this study, we aimed to produce data suitable for EUCAST to establish clinical MIC breakpoints and zone diameter correlates for Vibrio spp.

METHODS

An intercontinental collection (N = 524) comprising five important Vibrio spp. (V. alginolyticus, V. cholerae, V. fluvialis, V. parahaemolyticus and V. vulnificus) was organized. All isolates were subjected to broth microdilution (BMD) against 11 antimicrobial agents according to ISO 20776-1 using unsupplemented Mueller-Hinton broth on freeze-dried Sensititre panels (Thermo Scientific, UK), and most isolates (n = 371) were also tested with disc diffusion according to EUCAST methodology for non-fastidious organisms.

RESULTS

Aggregated results were used to generate MIC and zone diameter distributions and to prepare graphs of MIC-zone diameter correlation. Based on these results, the EUCAST Steering Committee determined clinical susceptible (S) and resistant (R) MIC (mg/L) breakpoints (S≤/R>) for the five Vibrio spp. for piperacillin/tazobactam (1/1), cefotaxime (0.25/0.25), ceftazidime (1/1), meropenem (0.5/0.5), ciprofloxacin (0.25/0.25), levofloxacin (0.25/0.25), azithromycin (4/4), doxycycline (0.5/0.5) and trimethoprim/sulfamethoxazole (0.25/0.25). The corresponding zone diameter breakpoints were identified.

CONCLUSIONS

We demonstrated the validity of using standard BMD and EUCAST disc diffusion methodology for AST of five Vibrio spp., and generated suitable data to allow EUCAST to determine clinical MIC and zone diameter breakpoints for five pathogenic Vibrio spp., including both non-toxigenic and toxigenic V. cholerae.

Understanding the connections between climate change, air pollution, and human health in Africa: Insights from a literature review

Climate change and air pollution are two interconnected global challenges that have profound impacts on human health. In Africa, a continent known for its rich biodiversity and diverse ecosystems, the adverse effects of climate change and air pollution are particularly concerning. This review study examines the implications of air pollution and climate change for human health and well-being in Africa. It explores the intersection of these two factors and their impact on various health outcomes, including cardiovascular disease, respiratory disorders, mental health, and vulnerable populations such as children and the elderly. The study highlights the disproportionate effects of air pollution on vulnerable groups and emphasizes the need for targeted interventions and policies to protect their health. Furthermore, it discusses the role of climate change in exacerbating air pollution and the potential long-term consequences for public health in Africa. The review also addresses the importance of considering temperature and precipitation changes as modifiers of the health effects of air pollution. By synthesizing existing research, this study aims to shed light on complex relationships and highlight the key findings, knowledge gaps, and potential solutions for mitigating the impacts of climate change and air pollution on human health in the region. The insights gained from this review can inform evidence-based policies and interventions to mitigate the adverse effects on human health and promote sustainable development in Africa.

Essential health services delivery and quality improvement actions under drought and food insecurity emergency in north-east Uganda

BACKGROUND

Essential health services can be disrupted due to several naturally occurring public health emergencies such as drought, flood, earthquake and outbreak of infectious diseases. However, little evidence exists on the status of essential health services delivery under the effect of drought and food insecurity. North-east Uganda is severely affected by prolonged drought that significantly affected the livelihood of the residents. Therefore, we aimed to determine the current status of essential health services and quality improvement (QI) actions in health facilities in north-east Uganda.

METHODS

We used a descriptive cross-sectional study design to assess the availability of essential health service and quality improvement activities in drought and food insecurity affected districts of north-east Uganda. We included a total of 150 health facilities from 15 districts with proportionated multistage sampling method. We interviewed health facilities' managers and services focal persons using structured questionnaire and observation checklist. We used a descriptive statistic to analyze the data with SPSS version 22.

RESULTS

A few health facilities (8.7%) had mental health specialist. There was also lack of capacity building training on essential health services. Considerable proportion of health facilities had no non-communicable diseases (38.3%), mental health (47.0%), and basic emergency obstetric care (40.3%) services. Stock out of essential medicines were observed in 20% of health facilities. There was lack of supportive supervision, and poor documentation of QI activities.

CONCLUSION

Essential health service and QI were suboptimal in drought and food insecure emergency affected districts. Human resource deployment (especially mental health specialist), provision of capacity building training, improving non-communicable diseases, mental health and basic emergency obstetric care services are required to improve availability of essential health services. Supporting supply chain management to minimize stock out of medicines, and promoting QI activities are also vital to assure quality of health service in drought and food insecurity affected districts in north-Eastern Uganda.

The specter of cholera in Libya and North Africa: Natural disasters and anthropization threaten human health during recent years

Introduction

According to data from the World Health Organization (WHO), in the last year cholera has re-emerged in various areas of the planet, particularly in Africa. The resurgence of this disease is closely linked to poor hygiene, which is sometimes the result of wars or environmental disasters, as in Lebanon and Syria since autumn 2022 and today in Libya.

Discussion

The spread of cholera is chiefly caused by the presence of contaminated water, in environments with inadequate hygiene and sanitation. Another cause, however, is the lack of access to adequate vaccination and treatment campaigns.

Method

In this short paper, the authors highlight the possibility of a resurgence of epidemic cholera in Libya, especially in light of the consequences of the devastating cyclone Daniel and the simultaneous collapse of two dams upstream of the city of Derna. They also highlight the concern that cholera and other infectious diseases may also spread in Morocco, which was hit by a severe earthquake on 8 September last. The focus of the paper is the awareness that the spread of epidemic diseases is very often linked to human actions, which may trigger or exacerbate the effects of natural disasters.

Conclusions

Since these events have devastating effects both on the environment and on people and their psychophysical balance, it is evident that we need to devote greater attention to the health of the planet, to which the health and survival of the human species is strictly and inextricably linked. Indeed, disasters related to phenomena of anthropization facilitate the spread of infectious diseases, placing a heavy burden on local and global health organizations and the health of entire populations. A change of course is therefore essential, in that human actions must be aimed at limiting rather than aggravating the spread of diseases.

Vibrio cholerae, classification, pathogenesis, immune response, and trends in vaccine development

Vibrio cholerae is the causative agent of cholera, a highly contagious diarrheal disease affecting millions worldwide each year. Cholera is a major public health problem, primarily in countries with poor sanitary conditions and regions affected by natural disasters, where access to safe drinking water is limited. In this narrative review, we aim to summarize the current understanding of the evolution of virulence and pathogenesis of V. cholerae as well as provide an overview of the immune response against this pathogen. We highlight that V. cholerae has a remarkable ability to adapt and evolve, which is a global concern because it increases the risk of cholera outbreaks and the spread of the disease to new regions, making its control even more challenging. Furthermore, we show that this pathogen expresses several virulence factors enabling it to efficiently colonize the human intestine and cause cholera. A cumulative body of work also shows that V. cholerae infection triggers an inflammatory response that influences the development of immune memory against cholera. Lastly, we reviewed the status of licensed cholera vaccines, those undergoing clinical evaluation, and recent progress in developing next-generation vaccines. This review offers a comprehensive view of V. cholerae and identifies knowledge gaps that must be addressed to develop more effective cholera vaccines.

Climate change and health risks in Mukuru informal settlement in Nairobi, Kenya - knowledge, attitudes and practices among residents

BACKGROUND

Residents of informal settlements in Sub-Sahara Africa (SSA) are vulnerable to the health impacts of climate change. Little is known about the knowledge, attitudes and practices (KAP) of inhabitants of informal settlements in SSA regarding climate change and its health impacts. The aim of this study was to investigate how inhabitants of an informal settlement in SSA experience climate change and its health impacts and assess related knowledge, attitudes and practices. The study was conducted in Mukuru informal settlement in Nairobi City County, Kenya.

METHODS

A cross-sectional study was conducted in September 2021 using a structured, semi-closed KAP questionnaire. Inclusion criteria were ≥ 18 years of age and living in one of the three main sections in Mukuru: Kwa Njenga, Kwa Reuben or Viwandani. By spinning a pen at the geographic centre of each section, a random direction was selected. Then, in every second household one individual was interviewed, creating a representative mix of ages and genders of the local community. To assess participant characteristics associated with climate change knowledge multivariable logistic regression was used. Thematic content analysis was performed for qualitative responses.

RESULTS

Out of 402 study participants, 76.4% (n = 307) had heard of climate change before the interview, 90.8% (n = 365) reported that climate change was affecting their community, and 92.6% (n = 372) were concerned with the health-related impact of climate change. Having lived in Mukuru for more than 10 years and living in a dwelling close to the riverside were factors significantly associated with having heard of climate change before (aOR 3.1, 95%CI 1.7 - 5.8 and aOR 2.6, 95%CI 1.1 - 6.1, respectively) and experiencing a climate change related impact on the community (aOR 10.7, 95%CI 4.0 - 28.4 and aOR 7.7; 95%CI 1.7 - 34.0, respectively). Chronic respiratory conditions, vector-borne diseases, including infectious diarrhoea, malnutrition and cardiovascular diseases were identified by respondents as climate related health risks.

CONCLUSIONS

Most respondents were knowledgeable about climate change and were experiencing its (health-related) impact on their community. This study provides insights which may prove useful for policy makers, intervention planners and researchers to work on locally adapted mitigation and adaption strategies.

Food insecurity and risk of cholera: A cross-sectional study and exploratory analysis of potential mediators

BACKGROUND

Food insecurity has been independently associated with developing cholera and there is an inverse relationship between national food security and annual cholera incidence. However, the factors that mediate the risk of cholera among food insecure households remain largely unexplored.

METHODOLOGY AND PRINCIPAL FINDINGS

In a cross-sectional survey of rural households in Haiti, we explored the role of food behaviors (i.e., dietary choices and food-handling practices) as mediators of cholera risk among food-insecure families. We generated a series of multivariable regression models to test hypothesized associations between the severity of food insecurity (measured by the Household Hunger Scale), hygiene and food behaviors, and history of severe, medically-attended cholera. Moderate household hunger (Adjusted Odds Ratio [AOR] 1.47, 95% Confidence Interval (CI) 1.05-2.04; p = 0.021) and severe hunger (AOR 2.45, 95% CI 1.45-4.15; p = 0.001) were positively associated with a history of severe, medically-attended cholera compared with little to no household hunger. Household hunger was positively associated with three behaviors: antacid use, consumption of leftover non-reheated food, and eating food and beverages prepared outside of the home (i.e., at a restaurant or from a vendor). Consumption of outside food items and antacid use were positively associated with a history of cholera.

CONCLUSION

Our findings suggest that food behaviors may mediate the association between food insecurity and cholera and contribute to an understanding of how interventions could be designed to target food insecurity as part of cholera prevention and control.

Gender Perspectives of Responses to Climate Variability and Change among Farm Households in Southeast Nigeria

It has been argued that gender affects climate change response especially among farming communities yet literature is scant on gender perspectives of response. In recognition of this, the study examined responses with the associated challenges and opportunities across gender in the South East (SE) Nigeria. A mixed research approach including a participatory research approach (PRA), field observation and household questionnaire survey was used to collect data. The survey sample included 300 (150 men and women each) farm household heads from six villages in the region. Data were analyzed and presented using principal component analysis (PCA), non-parametric and descriptive statistics. The study found that men and women-headed households differed in their use of strategies like migration from affected areas and livelihood diversification (p < 0.05). Women have more challenges of insufficient improved farming knowledge than men. The challenges for men were majorly insufficient technologies like mechanization. Components of these challenges include technology, environmental-related challenges among others. Response opportunities for men and women include digital/mobile telecommunications and learning by doing respectively. Compared to men, women had less participation in opportunities for the development of human capital through training (p < 0.05). The study recommends that more opportunities should be provided for the training of farmers especially women on climate change response.