Cholera; Vibrio cholerae; Epidemic spread; Spatiotemporal analysis; Clusters; Democratic Republic of the Congo
Abstract :
[en] Background: Cholera outbreaks in western Democratic Republic of the Congo (DRC) are thought to be primarily the result of westward spread of cases from the Great Lakes Region. However, other patterns of spatial spread in this part of the country should not be excluded. The aim of this study was to explore alternative routes of spatial spread in western DRC.
Methods: A literature review was conducted to reconstruct major outbreak expansions of cholera in western DRC since its introduction in 1973. We also collected data on cholera cases reported at the health zone (HZ) scale by the national surveillance system during 2000-2018. Based on data from routine disease surveillance, we identified two subperiods (week 45, 2012 – week 42, 2013 and week 40, 2017 – week 52, 2018) for which the retrospective space-time permutation scan statistic was implemented to detect spatiotemporal clusters of cholera cases and then to infer the spread patterns in western DRC other than that described in the literature.
Results: Beyond westward and cross-border spread in the West Congo Basin from the Great Lakes Region, other dynamics of cholera epidemic propagation were observed from neighboring countries, such as Angola, to non-endemic provinces of southwestern DRC. Space-time clustering analyses sequentially detected clusters of cholera cases from southwestern DRC to the northern provinces, demonstrating a downstream-to-upstream spread along the Congo River.
Conclusions: The spread of cholera in western DRC is not one-sided. There are other patterns of spatial spread, including a propagation from downstream to upstream areas along the Congo River, to be considered as preferential trajectories of cholera in western DRC.
Research Center/Unit :
SPHERES - ULiège
Disciplines :
Human health sciences: Multidisciplinary, general & others
Linard, Catherine ✱; UNamur - Université de Namur > Géographie
Bompangue, Didier ✱; Université de Kinshasa > Sciences de Base
Muwonga, Jérémie ✱; Université de Kinshasa > Biologie Médicale
MOUTSCHEN, Michel ✱; Université de Liège - ULiège > Département des sciences cliniques > Immunopathologie - Maladies infectieuses et médecine interne générale
Situakibanza, Hippolyte ✱; Université de Kinshasa > Médecine Interne
Ozer, Pierre ✱; Université de Liège - ULiège > Sphères
✱ These authors have contributed equally to this work.
Language :
English
Title :
The spread of cholera in western Democratic Republic of the Congo is not unidirectional from East–West: a spatiotemporal analysis, 1973–2018
Alternative titles :
[fr] La propagation du choléra dans l'ouest de la République démocratique du Congo n'est pas unidirectionnelle d'Est en Ouest : une analyse spatio-temporelle, 1973-2018
Original title :
[en] The spread of cholera in western Democratic Republic of the Congo is not unidirectional from East–West: a spatiotemporal analysis, 1973–2018