Main Article Content

Environmental factors associated with increased cholera cases in low-income districts in Zambia, 2017-2018


Nyambe Sinyange
Tadatsugu Imamura
Orbrie Chewe
Paul Msanzya Zulu
Fred Kapaya
Raymond Hamoonga
Mazyanga Lucy Mazaba
Muzala Kapina
Nathan Kapata
Edgar Simulundu
Victor Mukonka

Abstract

Introduction: Zambia is a cholera-endemic country and the epidemic in the capital, Lusaka, 2017-2018, caused more than 5,900 cases and  110 deaths. Low-income resident districts in Lusaka are known as hotspots for cholera outbreaks. Among these districts, Kanyama  sub-district has been the origin of the outbreaks in Lusaka, 2005-2006, 2016, and 2017-2018. However, spatial factors are associated with   the increased number of cholera cases in the Kanyama sub-district; the origin place is still not fully understood. We determined the  environmental factors associated with the increased cholera cases in the Kanyama sub-district by using geocoordinate data collected  during the outbreak in 2017-2018.


Methods: We conducted a retrospective data analysis on geocoordinate data of houses of cholera  cases identified in Kanyama sub-district during the outbreak in 2017-2018. Associations between the number of cases in each of the 218  generated zones within Kanyama sub-district and the distribution of environmental factors (e.g., water sources, toilets) were analyzed.  


Results: A total of 405 cholera cases were identified in 136 zones (62%, 136/218). Zones with cases had significantly larger numbers  (median, interquartile range; IQR) of toilets outside houses (56.5, 0-256; vs 35.5, 0-151; p<0.001) and pit latrines (51, 0-194; vs 28; 0- 117;  p<0.001), while significantly smaller number of water tanks than zones without cases (0, 0-21; vs 0.5, 0-19; p=0.021). The number of cases  showed a positive correlation with the number of toilets outside houses (rho=0.307, p<0.001) and pit latrines (rho=0.354, p=0.001).  


Conclusion: Lack of access to sanitary toilet facilities was associated with the increased number of cholera cases in Kanyama sub-district; the origin place of the recent cholera outbreaks in Lusaka, Zambia. Our study highlighted the importance of targeted public health  interventions to the sanitation systems in those areas.


Journal Identifiers


eISSN: 2664-2824