Stratifying the potential local transmission of Zika in municipalities of Antioquia, Colombia

Objective To stratify and understand the potential transmission processes of Zika virus in Colombia, in order to effectively address the efforts on surveillance and disease control. Methods We compare R0, of Zika for municipalities based on data from the regional surveillance system of Antioquia, Colombia. The basic reproduction number (R0) and its 95% confidence intervals were estimated from an SIR model with implicit vector dynamics, in terms of recovered individuals in each time unit, using an approximate solution. These parameters were estimated fitting the solution of the model to the daily cumulative frequency of each Zika case according to symptoms onset date relative to the index case reported to the local surveillance system. Results R0 was estimated for 20 municipalities with a median of 30,000 inhabitants, all located less than 2,200 m above sea level. The reported cases ranged from 17 to 347 between these municipalities within four months (January to April of 2016). The results suggest that 15 municipalities had a high transmission potential (R0>1), whereas in 5 municipalities transmission were potentially not sustaining (R01) and provide a technique to optimize surveillance and control of Zika. Health authorities should promote the collection, analysis, modeling and sharing of anonymous data onto individual cases to estimate R0. This article is protected by copyright. All rights reserved.