Conference abstract

Phylogenetic and phylodynamic analysis of the diffusion of dog rabies in Central and West Africa

Pan African Medical Journal - Conference Proceedings. 2019:10(5).14 Dec 2019.
doi: 10.11604/pamj-cp.2019.10.5.855

Contact the corresponding author
Keywords: Diffusion mechanism, genome sequence, rabies virus, transboundary exchange
Oral presentation

Phylogenetic and phylodynamic analysis of the diffusion of dog rabies in Central and West Africa

Stephanie Mauti1,2,3,&, Monique Lchenne2,3, Cline Mbilo2,3, Kemdongarti Nassengar4, Pati Pyana5, Emmanuel Nakoun6, Sandra Garba-Ouangole6, Rodrigue Poueme7, Grace Kia8, Emmanuel Balogun9, Ishaya Tekki10, Abdallah Traor11, Bassirou Bonfoh2,3,12, Garmie Voupawoe2,3,13, Simon Bonas1, Herve Bourhy1, Jakob Zinsstag2,3, Laurent Dacheux1

1Institut Pasteur, Unit Lyssavirus Dynamics and Host Adaptation, WHO Collaborating Centre for Reference and Research on Rabies, Paris, France, 2Swiss Tropical and Public Health Institute, Department of Epidemiology and Public Health, Basel, Switzerland, 3University of Basel, Basel, Switzerland, 4Institut de Recherche en Elevage pour le Dveloppement, N'Djamna, Chad, 5Institut National de Recherche Biomdicale (INRB), Kinshasa, Democratic Republic of Congo, 6Institut Pasteur de Bangui, Bangui, Rpublique Centrafricaine, 7Laboratoire National Vtrinaire, Garoua, Cameroun, 8Department of Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, Kaduna State Nigeria, 9Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University Zaria,Kaduna State Nigeria, 10National Veterinary Research Institute Vom, Plateau State Nigeria, 11Laboratoire Central Vtrinaire, Bamako, Mali, 12Centre Suisse de Recherches Scientifiques en Cte dIvoire, Abidjan, Cte d'Ivoire, 13Leon Quist Ledlum Central Veterinary Laboratory, Ministry of Agriculture, Monrovia, Republic of Liberia

&Corresponding author
Olubukola Olugasa, Department of Private and Commercial Law, School of Law and Security Studies, Ilisan-Remo, Ogun State, Nigeria


Introduction: canine rabies is the main cause of human rabies and is globally responsible for approximately 59 000 human deaths per year, nearly all occurring in low- and middle-income countries (LMICs). It is well known that mass dog vaccination is a cost-effective, sustainable measure to eliminate the disease at its source and prevent human exposure. However, implementation of vaccination campaigns in LMICs and maintenance of disease freedom in targeted regions remain highly challenging. It has been recently demonstrated, that two dog vaccination campaigns were sufficient to interrupt dog rabies transmission in NDjamena, the capital city of Chad in Central Africa. Unfortunately, canine rabies reappeared a few months after the end of the second campaign, suggesting that reintroduction may be due to influx of infected dogs from neighboring areas, which may be driven by human-mediated dispersal. It is also probable, that such rabies diffusion mechanism exists at larger scales, i.e. country level, and that transboundary exchanges occur. In addition to the role of humans in rabies spread, it is known that landscape features, such as rivers, mountains or deserts can act as natural barriers to disease spread. However, the precise mechanisms for rabies diffusion in dogs at both country level and interregional scale need to be further explored and in consideration of environmental and epidemiological parameters. The aim of this research project is to analyze dog rabies diffusion in Central and West Africa by combining landscape epidemiology with virus genetics.

Methods: phylogenetics and phylodynamics will be first elaborated for Central Africa with the analysis of animal rabies samples, which were recently collected in urban and rural areas of Chad, Cameroon, Central African Republic, Nigeria and the Democratic Republic of Congo. These analyses will be based on the full-length genome sequence, obtained by next generation sequencing (Illumina technology) with a dedicated bioinformatic workflow (implemented on the Galaxy platform). Based on this large dataset, Bayesian phylodynamic inferences will be conducted and the evolution of dog rabies virus will be estimated. In addition, patterns and drivers of virus spread will be determined and environmental and epidemiological factors from different local contexts will be included in the analyses. In the near future, we plan to expand our approach to West Africa, with the inclusion of Mali, Cte dIvoire and Liberia.

Results: it is expected that the combination of phylogenetic and phylodynamic analyses with landscape epidemiology will improve the resolution of surveillance in the selected African countries and contribute to understanding the geographical distribution and transboundary spread of the disease. We expect to identify main routes of virus transmission.

Conclusion: the generated knowledge will be further used for the placement of appropriate vaccine barriers and surveillance points and for the planning of dog vaccination campaigns in selected partner countries. Our approach is in line with the overarching aim to eliminate canine-mediated human rabies in Central and West Africa by 2030.