Using open-access data to explore relations between urban landscapes and diarrhoeal diseases in Côte d'Ivoire

Unlike water and sanitation infrastructures or socio-economic indicators, landscape features are seldomly considered as predictors of diarrhoea. In contexts of rapid urbanisation and changes in the physical environment, urban planners and public health managers could benefit from a deeper understanding of the relationship between landscape patterns and health outcomes. We conducted an ecological analysis based on a large ensemble of open-access data to identify specific landscape features associated with diarrhoea. Designed as a proof-of-concept study, our research focused on Côte d'Ivoire. This analysis aimed to (i) build a framework strictly based on open-access data and open-source software to investigate diarrhoea risk factors originating from the physical environment and (ii) understand whether different types and forms of urban settlements are associated with different prevalence rates of diarrhoea. We advanced landscape patterns as variables of exposure and tested their association with the prevalence of diarrhoea among children under the age of five years through multiple regression models. A specific urban landscape pattern was significantly associated with diarrhoea. We conclude that, while the improvement of water, sanitation, and hygiene infrastructures is crucial to prevent diarrhoeal diseases, the health benefits of such improvements may be hampered if the overall physical environment remains precarious

Environmental determinants of access to shared sanitation in informal settlements: a cross-sectional study in Abidjan and Nairobi

BACKGROUND: Universal access to basic sanitation remains a global challenge, particularly in low- and middle-income countries. Efforts are underway to improve access to sanitation in informal settlements, often through shared facilities. However, access to these facilities and their potential health gains-notably, the prevention of diarrheal diseases-may be hampered by contextual aspects related to the physical environment. This study explored associations between the built environment and perceived safety to access toilets, and associations between the latter and diarrheal infections. METHODS: A cross-sectional study was carried out between July 2021 and February 2022, including 1714 households in two informal settlements in Abidjan (Cote d'Ivoire) and two in Nairobi (Kenya). We employed adjusted odds ratios (aORs) obtained from multiple logistic regressions (MLRs) to test whether the location of the most frequently used toilet was associated with a perceived lack of safety to use the facility at any time, and whether this perceived insecurity was associated with a higher risk of diarrhea. The MLRs included several exposure and control variables, being stratified by city and age groups. We employed bivariate logistic regressions to test whether the perceived insecurity was associated with settlement morphology indicators derived from the built environment. RESULTS: Using a toilet outside the premises was associated with a perceived insecurity both in Abidjan [aOR = 3.14, 95% confidence interval (CI): 1.13-8.70] and in Nairobi (aOR = 57.97, 95% CI: 35.93-93.53). Perceived insecurity to access toilets was associated with diarrheal infections in the general population (aOR = 1.90, 95% CI: 1.29-2.79 in Abidjan, aOR = 1.69, 95% CI: 1.22-2.34 in Nairobi), but not in children below the age of 5 years. Several settlement morphology features were associated with perceived insecurity, namely, buildings' compactness, the proportion of occupied land, and angular deviation between neighboring structures. CONCLUSIONS: Toilet location was a critical determinant of perceived security, and hence, must be adequately addressed when building new facilities. The sole availability of facilities may be insufficient to prevent diarrheal infections. People must also be safe to use them. Further attention should be directed toward how the built environment affects safety

Healthy aging: comparative analysis of local perception and diet in two health districts of Côte d'Ivoire and Japan

Context: Good health and longevity depend on dynamic interactions between biological, social, psychological, and environmental factors. Aging is globally a big challenge, particularly with the demographic transition, including population growth, and an emerging burden to society. Knowledge, behavior, diet, and consumption of animal source food were related to aging and emerged as the key factors modulating healthy aging. Objective: The study was designed to understand the main healthy aging factors, such as knowledge, social network, and diet of elders, and to derive mutual learning from it for healthy aging. Methods: A qualitative approach has been applied to explore health-related knowledge, attitude, and diet of elders from Ebetsu (Japan) and Tiassale (Cote d'Ivoire) health districts, using focus group discussions and comparative context analysis between high- and low-income countries. Results: The study shows that living longer is a common feature of people in Japan compared to Cote d'Ivoire, where the life expectancy is still low. Both groups of elders have social networks that support them, and both offer their gained experience to society. While Japanese elders depend on pension and insurance for income and medical treatments, Ivorians depend mostly on their children and social network in old age. The worries of elders differ between the two regions. In Ebetsu, elder members of the community are concerned about the future burden they pose for the younger generation if they develop ill-health, making them more resilient to aging. In Taabo, elders are considered to be culturally and socially useful to the society. Elders in Ebetsu pointed out that for healthy aging, education on diet at a younger age, physical activities, and access to basic social services are the key aspects. This was not observed in Taabo's context. Being inactive and dependent on others were described as the most worrying situations for elders in Ebetsu, as it is perceived to increase the risk of non-communicable diseases and anxiety. Elders in Ebetsu have good knowledge on what constitutes a healthy diet, and they believe that diversifying their diet, reducing portions, and substituting red meat with good animal and vegetable proteins are best eating practices to maintain good health. In Cote d'Ivoire, the diet is imbalanced and the whole family consumes the same meal made mainly with high-energy staples and little protein. However, it is observed in both societies that adopting a good diet is very expensive. Conclusion: The consciousness of aging is universal, but healthy aging varies according to the social systems, education, and knowledge on diet transition. Physical activities, protein-energy balance in diet, and social networks are the key for healthy aging in both contexts. The challenge is to find ways to increase knowledge regarding healthy aging and to strengthen the support system so that healthy aging becomes affordable

Diagnosis, clinical features, and self-reported morbidity of Strongyloides stercoralis and hookworm infection in a Co-endemic setting

BACKGROUND: Infections with Strongyloides stercoralis and other helminths represent important, yet often neglected issues in developing countries. Indeed, strongyloidiasis can be fatal, but only a few studies provide information regarding its health relevance in Africa. Moreover, clinical data on symptomatology and typical recognition patterns mainly originate from Western travel clinics. METHODOLOGY: A cross-sectional epidemiological survey was carried out in a rural part of south-central Côte d'Ivoire. Stool samples from 292 randomly selected individuals were examined for intestinal helminths, using a suite of diagnostic techniques (i.e., Kato-Katz, Baermann funnel, and Koga agar plate). Participants were interviewed with a pre-tested questionnaire and clinically examined. Multivariate logistic regression analysis was done to relate perceived morbidity and clinical findings to helminth infection status. PRINCIPAL FINDINGS: The prevalence of hookworm and S. stercoralis was 51.0% and 12.7%, respectively. Both infections were strongly associated with each other (adjusted odds ratio, 6.73; P < 0.001) and higher prevalences were observed with age. S. stercoralis-infected individuals expressed self-reported morbidity considerably more often than those with hookworm infection. Clinical examination identified high prevalences of various pathologies and detected tendencies to worse health conditions in helminth-infected subjects. CONCLUSIONS/SIGNIFICANCE: The use of multiple diagnostic tools showed that S. stercoralis and hookworm are co-endemic in rural Côte d'Ivoire and that each infection causes clinical symptoms and sequelae. Our findings are important for (re-)estimating the burden of helminth infections, and highlight the need for integrating epidemiological surveys, rigorous diagnostic approaches, and clinical assessments in the developing world

Enhanced ocean carbon storage from anaerobic alkalinity generation in coastal sediments

The coastal ocean is a crucial link between land, the open ocean and the atmosphere. The shallowness of the water column permits close interactions between the sedimentary, aquatic and atmospheric compartments, which otherwise are decoupled at long time scales (≅ 1000 yr) in the open oceans. Despite the prominent role of the coastal oceans in absorbing atmospheric CO2 and transferring it into the deep oceans via the continental shelf pump, the underlying mechanisms remain only partly understood. Evaluating observations from the North Sea, a NW European shelf sea, we provide evidence that anaerobic degradation of organic matter, fuelled from land and ocean, generates total alkalinity (AT) and increases the CO2 buffer capacity of seawater. At both the basin wide and annual scales anaerobic AT generation in the North Sea's tidal mud flat area irreversibly facilitates 7–10%, or taking into consideration benthic denitrification in the North Sea, 20–25% of the North Sea's overall CO2 uptake. At the global scale, anaerobic AT generation could be accountable for as much as 60% of the uptake of CO2 in shelf and marginal seas, making this process, the anaerobic pump, a key player in the biological carbon pump. Under future high CO2 conditions oceanic CO2 storage via the anaerobic pump may even gain further relevance because of stimulated ocean productivity

Small-scale field evaluation of PermaNet® Dual (a long-lasting net coated with a mixture of chlorfenapyr and deltamethrin) against pyrethroid-resistant Anopheles gambiae mosquitoes from Tiassalé, Côte d'Ivoire

BACKGROUND: Due to the rapid expansion of pyrethroid-resistance in malaria vectors in Africa, Global Plan for Insecticide Resistance Management (GPIRM) has recommended the development of long-lasting insecticidal nets (LLINs), containing insecticide mixtures of active ingredients with different modes of action to mitigate resistance and improve LLIN efficacy. This good laboratory practice (GLP) study evaluated the efficacy of the chlorfenapyr and deltamethrin-coated PermaNet((R)) Dual, in comparison with the deltamethrin and synergist piperonyl butoxide (PBO)-treated PermaNet((R)) 3.0 and the deltamethrin-coated PermaNet((R)) 2.0, against wild free-flying pyrethroid-resistant Anopheles gambiae sensu lato (s.l.), in experimental huts in Tiassale, Cote d'Ivoire (West Africa). METHODS: PermaNet((R)) Dual, PermaNet((R)) 3.0 and PermaNet((R)) 2.0, unwashed and washed (20 washes), were tested against free-flying pyrethroid-resistant An. gambiae s.l. in the experimental huts in Tiassale, Cote d'Ivoire from March to August 2020. Complementary laboratory cone bioassays (daytime and 3-min exposure) and tunnel tests (nightly and 15-h exposure) were performed against pyrethroid-susceptible An. gambiae sensu stricto (s.s.) (Kisumu strain) and pyrethroid-resistant An. gambiae s.l. (Tiassale strain). RESULTS: PermaNet((R)) Dual demonstrated significantly improved efficacy, compared to PermaNet((R)) 3.0 and PermaNet((R)) 2.0, against the pyrethroid-resistant An. gambiae s.l. Indeed, the experimental hut trial data showed that the mortality and blood-feeding inhibition in the wild pyrethroid-resistant An. gambiae s.l. were overall significantly higher with PermaNet((R)) Dual compared with PermaNet((R)) 3.0 and PermaNet((R)) 2.0, for both unwashed and washed samples. The mortality with unwashed and washed samples were 93.6 +/- 0.2% and 83.2 +/- 0.9% for PermaNet((R)) Dual, 37.5 +/- 2.9% and 14.4 +/- 3.9% for PermaNet((R)) 3.0, and 7.4 +/- 5.1% and 11.7 +/- 3.4% for PermaNet((R)) 2.0, respectively. Moreover, unwashed and washed samples produced the respective percentage blood-feeding inhibition of 41.4 +/- 6.9% and 43.7 +/- 4.8% with PermaNet((R)) Dual, 51.0 +/- 5.7% and 9.8 +/- 3.6% with PermaNet((R)) 3.0, and 12.8 +/- 4.3% and - 13.0 +/- 3.6% with PermaNet((R)) 2.0. Overall, PermaNet((R)) Dual also induced higher or similar deterrence, exophily and personal protection when compared with the standard PermaNet((R)) 3.0 and PermaNet((R)) 2.0 reference nets, with both unwashed and washed net samples. In contrast to cone bioassays, tunnel tests predicted the efficacy of PermaNet((R)) Dual seen in the current experimental hut trial. CONCLUSION: The deltamethrin-chlorfenapyr-coated PermaNet((R)) Dual induced a high efficacy and performed better than the deltamethrin-PBO PermaNet((R)) 3.0 and the deltamethrin-only PermaNet((R)) 2.0, testing both unwashed and 20 times washed samples against the pyrethroid-susceptible and resistant strains of An. gambiae s.l. The inclusion of chlorfenapyr with deltamethrin in PermaNet((R)) Dual net greatly improved protection and control of pyrethroid-resistant An. gambiae populations. PermaNet((R)) Dual thus represents a promising tool, with a high potential to reduce malaria transmission and provide community protection in areas compromised by mosquito vector resistance to pyrethroids

Prevalence of Schistosoma mono- and co-infections with multiple common parasites and associated risk factors and morbidity profile among adults in the Taabo health and demographic surveillance system, South-Central Côte d'Ivoire

BACKGROUND: Schistosomiasis remains an important public health problem, also among adults, and infected individuals not treated serve as a reservoir for continued transmission. Despite this fact, evidence on the epidemiology of schistosomiasis in adults in Cote d'Ivoire is scanty. This study aimed to determine the prevalence and risk factors of Schistosoma infection and co-infection with other helminth species and Plasmodium among adults in the Taabo region in the south-central part of Cote d'Ivoire. METHODS: A cross-sectional survey was carried out in April and May 2017 in the frame of the "Cote d'Ivoire Dual Burden of Disease Study" (CoDuBu). A total of 901 randomly selected individuals, aged 18-90 years, provided blood, stool and urine samples for the diagnosis of malaria and helminth infections. Stool samples were subjected to the Kato-Katz technique for detection of Schistosoma mansoni and soil-transmitted helminth eggs, while urine samples were examined for eggs of Schistosoma haematobium and circulating cathodic antigen of S. mansoni. Risk factors and morbidity profiles were assessed using health examination and questionnaires. Multinomial logistic regressions were employed to identify risk factors and morbidity patterns associated with S. mansoni mono- and co-infections. RESULTS: The prevalence of S. mansoni and S. haematobium was 23.2% and 1.0%, respectively. Most S. mansoni were mono-infections (81.3%). Independent determinants of S. mansoni infection were young age, low socioeconomic status (mono- and co-infection) and poor hygiene practices (co-infection) (P < 0.05). S. mansoni infection was independently associated with higher pain and symptom scores (mono-infection), poor self-rated health and low healthcare use (co-infection) (P < 0.05). CONCLUSIONS: This study showed that adults represent a substantial reservoir of S. mansoni. To sustain schistosomiasis control and improve people's wellbeing, it is important to expand preventive chemotherapy from school-aged children to adults, coupled with hygiene and health education

Leishmaniasis, Autoimmune Rheumatic Disease, and Anti–Tumor Necrosis Factor Therapy, Europe

We report 2 cases of leishmaniasis in patients with autoimmune rheumatic diseases in Greece. To assess trends in leishmaniasis reporting in this patient population, we searched the literature for similar reports from Europe. Reports increased during 2004–2008, especially for patients treated with anti–tumor necrosis factor agents

High levels of Plasmodium falciparum rosetting in all clinical forms of severe malaria in African children

Plasmodium falciparum rosetting (the spontaneous binding of infected erythrocytes to uninfected erythrocytes) is a well-recognized parasite virulence factor. However, it is currently unclear whether rosetting is associated with all clinical forms of severe malaria, or only with specific syndromes such as cerebral malaria. We investigated the relationship between rosetting and clinical malaria in 209 Malian children enrolled in a case-control study of severe malaria. Rosetting was significantly higher in parasite isolates from severe malaria cases compared with non-severe hyperparasitemia and uncomplicated malaria controls (F(2,117) = 8.15, P < 0.001). Analysis of sub-categories of severe malaria (unrousable coma, severe anemia, non-comatose neurological impairment, repeated seizures or a small heterogeneous group with signs of renal failure or jaundice) showed high levels of rosetting in all sub-categories, and no statistically significant differences in rosetting between sub-categories (F(4,67) = 1.28, P = 0.28). Thus rosetting may contribute to the pathogenesis of all severe malaria syndromes in African children, and interventions to disrupt rosetting could be potential adjunctive therapies for all forms of severe malaria in Africa