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Background: There is limited data on the association between diarrhoea among children aged under five years (U5D) and water use, sanitation, hygiene, and socio-economics factors in low-income communities. The study investigated U5D and the associated risk factors in the Zeekoe catchment in Cape Town, South Africa. Methods: A cross-sectional study was conducted in 707 households in six informal settlements (IS) two formal settlements (FS) (March–June 2017). Results: Most IS households used public taps (74.4%) and shared toilets (93.0%), while FS households used piped water on premises (89.6%) and private toilets (98.3%). IS respondents had higher average hand-washing scores than those of FS (0.04 vs. −0.14, p = 0.02). The overall U5D prevalence was 15.3% (range: 8.6%–24.2%) and was higher in FS than in IS (21.2% vs. 13.4%, respectively, p = 0.01). Water storage >12 h was associated with increasing U5D (OR = 1.88, 95% CI 1.00–3.55, p = 0.05). Water treatment (OR = 0.57, 95%CI 0.34–0.97, p = 0.04), good hand-washing practices (OR = 0.59, 95%CI 0.42–0.82, p = 0.002) and Hepatitis A vaccination (OR = 0.51, 95%CI 0.28–0.9, p = 0.02) had significant preventing effects on U5D. Conclusions: The study highlights that good hygiene practice is a key intervention against U5D in informal settlements. The promotion of hand-washing, proper water storage, and hygienic breastfeeding is highly recommended.

South Africa has been facing significant challenges in meeting demands in its water and energy sectors in recent years and planning for both sectors has mostly been done separately. The City of Cape Town has started to supplement its dwindling conventional freshwater supplies with groundwater, wastewater and seawater, in light of the drought that commenced in 2015. The Cape Flats Aquifer in Cape Town represents an important resource whose yield could be increased to 85 000 m3/ day through artificial stormwater recharge in the Zeekoe Catchment alone. The abstraction and treatment of this water would require significant amounts of energy and thus this paper explores the links between energy usage in the water sector and its carbon footprint. The three alternatives investigated were ‘centralised’, ‘desalination’ and ‘decentralised’ approaches. The former two are centralised treatment mechanisms to produce potable water utilising existing and new treatment infrastructure, respectively, and the latter proposed minimal treatment for non-potable end-users. The energy intensities of the alternatives were evaluated by identifying energy-intensive components and carrying out a preliminary design of the networks and the required treatment mechanisms. South Africa’s future potential electricity mixes were used to conceptualise the significance of the associated energy demand. The centralised approach’s energy intensity was found to be the lowest of the three, ranging from 1.16 to 1.57 MJ/m3, while those of the decentralised and desalination approaches ranged from 3.57 to 7.31 MJ/m3 and 7.41 to 9.62 MJ/m3, respectively. The Western Cape Water Supply System has an installed capacity of 47.6 MW which could potentially increase by at least 2.7%, 5.7% and 12.3% through the centralised, decentralised and desalination options, respectively. This paper contributes to a growing knowledge on the water–energy nexus in South Africa.

Insects exhibiting swarming habits in Lake Victoria include mainly the Chironomidae, the Chaoboridae and Povilla adusta (Ephemeroptera). Their early life cycles are spent in the lake as benthos and standard bathymetric procedures were undertaken to estimate the standing crop biomass of the larvae in Murchison Bay. Povilla was principally a boring invertebrate preferring dried logs (113 g Povilla nymphs per kg of host plant material). Cyperuspapyrus carried 5 g C. denudatus 2.5 g and Phragmites mauritanus 1.0 g of Povilla per kg of host plant material. Povilla also occurred in the benthos at 40 g/m 2 . The Chironomidae and Chaoboridae had a mean standing crop biomass of 80 g/m 2 and 3 g/m 2 respectively. Their total biomass for the bay was estimated at 16060 metric tonnes for the Chironomidae, 7920 m. t. for Povilla and 660 m. t. for the Chaoborids. Adult swarming habits of the lakefiy were closely correlated with lunar phases and the adu Its were easily trapped at night using kerosene lamps. Biochemical tests of the nutrient value of lakefiy showed high levels of protein content (62%), minerals (18%), a low fat content (3.9%) and low moisture content (9%). This makes the lakefiy ideal as an additive in animal feeds and growth experiments with poultry and aquaculture fish are currently going on to test the suitability of lakefiy as an ingredient in animal feeds. Resume-Les insectesessaiment dans le Lac Victoria comprennent surtout les Chironomidae, les Chaoboridae et Povilla adusta (Ephemeroptera). La premiere partie de leur cycle est passee dans le Lac comme benthos et des proced ures standard de Bathymetrie e talent utilisees pour estimer la biomass des larves dans MurchisonBay. Povilla etait principalement un invertebre qui p re fere des pieces de bois sec he (113 gr Povilla nymphes par kilo de materiel vegetal). Cyperus papyrus avait 5 gr., C. dennatus 2.5 gr., et Phragmites mauritanus 1.0 gr. de Povilla par kilo de materiel vegetal. Povilla etait aussi present dans le benthos avec une densite de 40 gr. par metre carre. Les Chironomidae avait une densite moyenne de 80 gr. par metre carre, les Chaoboridae 3 gr. par metre carree. La biomasse totale de Murchison Bay est estimee a 16060 tonnes pour les Chironomidae, 7920 tonnes pour Povilla et 660 tonnes pour les Chironomidae, 7920 tonnes pour Povilla et 660 tonnes pour les Chaoborides. Le comportement d'essaimage des mouches du lac etait en forte correlation avec le cycle de la lune, et les adultes etait faciles a capturer pendant la nuit avec des lampes a kerosene. Des test biochemiques de la valeur nutritive des mouches du lac demontraient une haute contenance enproteine(62%),mineraux(18%), unefaiblecontenancedegras(3.9%)etd'eau(9%).Ced rend la mouchedu lac une addition ideale pour la nutrition d'animaux,et des experiences avec des poules et aquaculture de poisson sont en cours, pour etudier la faisabilite d'utiliser cette mouche comme ingredient dans les nutritiments pour animaux. 137 138 J. OKEDI