Présentation du modèle de propagation du Chikungunya au Congrès ASAIHL à Montpellier le 12 juin 2014, pour lequel je suis co-auteur s'agissant de la partie clinique.
A holistic approach for modeling the
dynamic of chikungunya and developing control actions
Roger Frutos1,2,*, Aurélie Merlin3, Siobhan Staunton4, Patrice Ravel5,
Mireille Fargette3, Hervé Quiquanpoix5, Tri Baskoro Tunggul Satoto6,
Erna Andayani7, Susi Damayanti6,
Guilhem Kister5,
Yannick Bardie8, Emmanuel Cornillot1, Christian Devaux1,
Catherine Moulia9, Laurent Gavotte9 Thérèse Libourel3,
Laurence Briant1, Nathalie Chazal1
1: Centre
d’étude des Pathogènes et Biotechnologies pour la Santé, CPBS, UMR 5236 CNRS -
UM1- UM2, Montpellier, France
2: Intertryp, UMR 77 CIRAD-IRD, Montpellier, France
3: Espace Dev, UMR IRD-UM2-UAG-ULR, Montpellier, France
4: Eco&Sols, UMR 210, INRA-IRD-CIRAD-Supagro, Montpellier France
5: Laboratoire de physique industrielle et
traitement de l’information, EA2415 UM1,
Montpellier, France
6: Center for Tropical Medicine, Faculty of Medicine, Gadjah Mada
University, Yogyakarta, Indonesia
7: Sukoharjo Regency Health Center, Center of Java,
Sukoharjo, Indonesia
8:
Intelligence in Life – R&D Clinique SARL, Montpellier, France
9: Institut des Sciences de l’Evolution de
Montpellier - ISEM, UMR 5557 CNRS – UM2, Montpellier, France
Objectives: We
developed integrative approaches for the study of emerging diseases. Chikungunya virus (CHIKV), a
mosquito-borne pathogen from the alphavirus
genius transmitted by Aedes mosquitoes (Aedes aegypti and Aedes albopictus) causes acute infection in humans characterized by
rash, high fever and, its hallmark feature is a severe arthritis that can
persist for years. These disease was taken as a model system. Modeling
the dynamic of the disease in Asia, where the CHIKV is actively propagating, is
essential to develop prevention strategies for regions with high risk of
propagation, including Europe where the vector A. albopictus is now well established. Multidisciplinary and
multi-scale approaches are considered in our solutions.
Methods: We have
constructed an object model (UML class diagram) to describe the structure of
the system. This object model has been extended to dengue. The modeling of the
dynamic of the transmission of CHIKV was performed with a multi-agent system
implemented on the Netlogo platform. A case study has been selected in the
region of Yogyakarta-Sukoharjo, Indonesia to validate both static and dynamic
models. Information relative to geolocalisation, demography, environment
(rural, urban, industrial, …), clinical information, vector population, has
been collected on the field using standardized procedures.
Results: The class
diagram defines the compartments of the model. We carefully describe
compartments concerning environment description (description referring to
geographic standards, ecology, anthropic influence), sample description
(vector, human, virus triptych), clinical data (including media influence) and
diagnostic tools. Data have been collected in a periurban zone of Yogyakarta
(RT42) and a rural section of Sukoharjo district (RT02 and RT03). A
questionnaire to collect clinical information has been set up following OBOE
standard and presented to the local health centers. The index case was
successfully established in the rural region. SEIR (Sensitive/Exposed/Infected/Resistant)
compartments were considered for the host while SEI (Sensitive/Exposed/Infected)
were selected for the vector to establish the dynamic model. We have been able
to test the influence of medical care policies, vector control options and external
income of virus. We also develop analyses on the fate and persitance of
mosquitocidal agents post treatment.
Conclusion: We have
tested the influence of medical practices in the development of the illness.
Isolation of patients during the acute initial phase of the infection would
avoid transmission and should drastically reduce the transmission of the virus.
According to our study, the presence of large factories in the region of Sukoharjo
is suspected to constitute the major source of CHIKV for the region. Whether
factories provide suitable habitat for local populations of vector and whether
industrial activity contributes to the introduction of populations originating elsewhere
will be tested by further serological and molecular analyses.
