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DOI: 10.1016/j.jtbi.2013.11.024

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# Epidemic dynamics of a vector-borne disease on a villages-and-city star network with commuters

## Emmanuel A. Mpolya,Kenta Yashima,Hisashi Ohtsuki,Akira Sasaki

Artificial intelligence

Recombinant DNA

Mathematics

We develop a star-network of connections between a central city and peripheral villages and analyze the epidemic dynamics of a vector-borne disease as influenced by daily commuters. We obtain an analytical solution for the global basic reproductive number R0 and investigate its dependence on key parameters for disease control. We find that in a star-network topology the central hub is not always the best place to focus disease intervention strategies. Disease control decisions are sensitive to the number of commuters from villages to the city as well as the relative densities of mosquitoes between villages and city. With more commuters it becomes important to focus on the surrounding villages. Commuting to the city paradoxically reduces the disease burden even when the bulk of infections are in the city because of the resulting diluting effects of transmissions with more commuters. This effect decreases with heterogeneity in host and vector population sizes in the villages due to the formation of peripheral epicenters of infection. We suggest that to ensure effective control of vector-borne diseases in star networks of villages and cities it is also important to focus on the commuters and where they come from.

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¤ Open Access

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¤ Open Access

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<I>Anopheles gambiae</I> s.l. and <I>Anopheles funestus</I> Mosquito Distributions at 30 Villages along the Kenyan Coast

This study investigated whether Anopheles gambiae s.l. and Anopheles funestus Giles mosquito populations were distributed randomly among houses on the coast of Kenya. Sample means and variances of mosquitoes were estimated from bimonthly pyrethrum spray collections at 30 villages from July 1997 through May 1998. In total, 5,476 An. gambiae s.l. and 3,461 An. funestus were collected. The number of An. gambiae s.l. collected was highest in November/December and lowest in May. The number of An. funestus collected was highest during September/October and lowest during May. As the density of mosquitoes decreased, there was a tendency toward randomness in the distribution. The proportion of An. gambiae s.l. and An. funestus mosquitoes collected per house for each sampling period also showed patterns of clustering, with 80% of An. gambiae s.l. collected from <30% of the houses and 80% of An. funestus collected from <20% of the total houses. The total number of mosquitoes collected from any one house ranged from 0 to 121 for An. gambiae s.l. and from 0 to 152 for An. funestus. This coupled with the results of the variance to mean ratio plots suggests extensive clustering in the distribution of An. gambiae s.l. and An. funestus mosquito populations throughout the year along the coast of Kenya.

“Epidemic dynamics of a vector-borne disease on a villages-and-city star network with commuters” is a paper by Emmanuel A. Mpolya Kenta Yashima Hisashi Ohtsuki Akira Sasaki published in the journal Journal of Theoretical Biology in 2014. It was published by Elsevier. It has an Open Access status of “green”. You can read and download a PDF Full Text of this paper here.