Projecting the end of the Zika virus epidemic in Latin America: a modelling analysis

Kathleen M O’Reilly; Rachel Lowe; W John Edmunds; Philippe Mayaud; Adam Kucharski; Rosalind M Eggo; Sebastian Funk; Deepit Bhatia; Kamran Khan; Moritz U Kraemar; Annelies Wilder-Smith; Laura C Rodrigues; Patricia Brasil; Eduardo Massad; Thomas Jaenisch; Simon Cauchemez; Oliver J Brady; Laith Yakob

A deterministic meta-population model was used for ZIKV transmission between major cities in the LAC region. Cities with a population larger than 750,000 and large Caribbean islands were included in the model. In total we considered 91 cities. We extracted population sizes using the UN estimates from 2015. 25 Migration between cities was modelled assuming several scenarios: i) a gravity model with no exponential terms; ii) a gravity model with estimated exponential terms; iii) a radiation model; iv) a data-driven approach based on flight data; and v) a model of local radiation and flight movements. Gravity models assume that movement between cities is highest when located near each other and when both cities are large. Radiation models assume that movement between cities are affected by the size of the population in a circle between the cities (see Supporting Information S2 for further information).