TY - JOUR
T1 - The spread of cholera in western Democratic Republic of the Congo is not unidirectional from East–West
T2 - a spatiotemporal analysis, 1973–2018
AU - Kayembe, Harry César Ntumba
AU - Linard, Catherine
AU - Bompangue, Didier
AU - Muwonga, Jérémie
AU - Moutschen, Michel
AU - Situakibanza, Hippolyte
AU - Ozer, Pierre
N1 - Funding Information:
We are grateful to the Académie de Recherche et d’Enseignement Supérieur (ARES). We also thank Dr Bien-Aimé Mandja for his participation in the analysis and interpretation of the data, and all staff of the Research and Training Unit on Ecology and Control of Infectious Diseases [Unité de Recherche et de Formation en Écologie et Contrôle des Maladies Infectieuses (URF-ECMI)].
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/12
Y1 - 2021/12
N2 - 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.
AB - 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.
KW - Cholera
KW - Clusters
KW - Democratic Republic of the Congo
KW - Epidemic spread
KW - Spatiotemporal analysis
KW - Vibrio cholerae
UR - http://www.scopus.com/inward/record.url?scp=85121433233&partnerID=8YFLogxK
U2 - 10.1186/s12879-021-06986-9
DO - 10.1186/s12879-021-06986-9
M3 - Article
C2 - 34923959
AN - SCOPUS:85121433233
VL - 21
JO - BMC Infectious Diseases
JF - BMC Infectious Diseases
IS - 1
M1 - 1261
ER -