Assessing transmission patterns of flood-related waterborne diseases in two urban municipalities of Côte d’Ivoire

Abstract Flooding increases with climate variabilities and results in health risk factors in urban settings with poor sanitation infrastructure. Expert previsions highlight that by 2030, climate change and change in land-use will increase waterborne disease transmissions. However, there are few assessments of the indirect impacts of flooding, such as waterborne pathogens and zoonoses. This research aimed at assessing flooding-related disease transmission patterns in two municipalities (Abobo and Cocody) of Abidjan in Côte d’Ivoire. The study applied a cross-sectional survey with 844 households. Overall, 200 samples of rainwater from flooded households and drainage streams were collected, followed by laboratory analyses. Giardia lamblia and Vibrio cholerae spp. concentrations were assessed using the Sodium Acetate Formalin (SAF) method and the most probable number (MPN) method, respectively. Blood and urine were sampled from 129 rodents captured in households, followed by a PCR analysis to detect Leptospira species. The results show no significant difference detected in household exposure to flooding associated with solid waste management. In flooded households, perceived malaria symptoms and diarrhoea are associated with education (OR = 0.8, 95% CI 0.7–0.8, p = 0.001) and waste disposal (OR = 1.4, 95% CI 1.2–1.6, p = 0.001). There was no V. cholerae detected in the flood water. A total of 77 cyst/ml of Giardia lamblia were found in the flood water in Abobo. Three species of rodents were identified (Mus musculus, Crocidura, Rattus), and there is no Leptospira spp. detected in water, blood and urine. The presence of waterborne pathogens associated with flood water highlighted mainly faecal contamination risk. Further interventions should focus on sanitation that reduce faecal contamination.