TY - JOUR

T1 - Estimation of the reproduction number of dengue fever from spatial epidemic data

AU - Chowell, G.

AU - Diaz-Dueñas, P.

AU - Miller, J. C.

AU - Alcazar-Velazco, A.

AU - Hyman, J. M.

AU - Fenimore, P. W.

AU - Castillo-Chavez, Carlos

N1 - Funding Information:
We thank an anonymous reviewer for providing useful comments that helped to improve our manuscript. This work was carried out under the auspices of the National Nuclear Security Administration of the US Department of Energy at Los Alamos National Laboratory under Contract No. DE-AC52-06NA25396 and was partially supported by the NNSA’s Laboratory Directed Research and Development Program.

PY - 2007/8

Y1 - 2007/8

N2 - Dengue, a vector-borne disease, thrives in tropical and subtropical regions worldwide. A retrospective analysis of the 2002 dengue epidemic in Colima located on the Mexican central Pacific coast is carried out. We estimate the reproduction number from spatial epidemic data at the level of municipalities using two different methods: (1) Using a standard dengue epidemic model and assuming pure exponential initial epidemic growth and (2) Fitting a more realistic epidemic model to the initial phase of the dengue epidemic curve. Using Method I, we estimate an overall mean reproduction number of 3.09 (95% CI: 2.34, 3.84) as well as local reproduction numbers whose values range from 1.24 (1.15, 1.33) to 4.22 (2.90, 5.54). Using Method II, the overall mean reproduction number is estimated to be 2.0 (1.75, 2.23) and local reproduction numbers ranging from 0.49 (0.0, 1.0) to 3.30 (1.63, 4.97). Method I systematically overestimates the reproduction number relative to the refined Method II, and hence it would overestimate the intensity of interventions required for containment. Moreover, optimal intervention with defined resources demands different levels of locally tailored mitigation. Local epidemic peaks occur between the 24th and 35th week of the year, and correlate positively with the final local epidemic sizes (ρ = 0.92, P-value < 0.001). Moreover, final local epidemic sizes are found to be linearly related to the local population size (P-value < 0.001). This observation supports a roughly constant number of female mosquitoes per person across urban and rural regions.

AB - Dengue, a vector-borne disease, thrives in tropical and subtropical regions worldwide. A retrospective analysis of the 2002 dengue epidemic in Colima located on the Mexican central Pacific coast is carried out. We estimate the reproduction number from spatial epidemic data at the level of municipalities using two different methods: (1) Using a standard dengue epidemic model and assuming pure exponential initial epidemic growth and (2) Fitting a more realistic epidemic model to the initial phase of the dengue epidemic curve. Using Method I, we estimate an overall mean reproduction number of 3.09 (95% CI: 2.34, 3.84) as well as local reproduction numbers whose values range from 1.24 (1.15, 1.33) to 4.22 (2.90, 5.54). Using Method II, the overall mean reproduction number is estimated to be 2.0 (1.75, 2.23) and local reproduction numbers ranging from 0.49 (0.0, 1.0) to 3.30 (1.63, 4.97). Method I systematically overestimates the reproduction number relative to the refined Method II, and hence it would overestimate the intensity of interventions required for containment. Moreover, optimal intervention with defined resources demands different levels of locally tailored mitigation. Local epidemic peaks occur between the 24th and 35th week of the year, and correlate positively with the final local epidemic sizes (ρ = 0.92, P-value < 0.001). Moreover, final local epidemic sizes are found to be linearly related to the local population size (P-value < 0.001). This observation supports a roughly constant number of female mosquitoes per person across urban and rural regions.

KW - Colima

KW - Dengue

KW - Dengue hemorrhagic fever

KW - Mathematical model

KW - Mexico

KW - Reproduction number

KW - Spatial epidemic data

KW - Stage progression

UR - http://www.scopus.com/inward/record.url?scp=34547135991&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34547135991&partnerID=8YFLogxK

U2 - 10.1016/j.mbs.2006.11.011

DO - 10.1016/j.mbs.2006.11.011

M3 - Article

C2 - 17303188

AN - SCOPUS:34547135991

VL - 208

SP - 571

EP - 589

JO - Mathematical Biosciences

JF - Mathematical Biosciences

SN - 0025-5564

IS - 2

ER -