Rxivist logo

The Epidemiology and Transmissibility of Zika Virus in Girardot and San Andres Island, Colombia

By Diana Patricia Rojas, Natalie E Dean, Yang Yang, Eben Kenah, Juliana Quintero, Simon Tomasi, Erika L. Ramirez, Yendy Kelly, Carolina Castro, Gabriel Carrasquilla, M. Elizabeth Halloran, Ira M. Longini

Posted 24 Apr 2016
bioRxiv DOI: 10.1101/049957 (published DOI: 10.2807/1560-7917.ES.2016.21.28.30283)

Background: Zika virus (ZIKV) is an arbovirus in the same genus as dengue virus and yellow fever virus. ZIKV transmission was first detected in Colombia in September 2015. The virus has spread rapidly across the country in areas infested with the vector Aedes aegypti. As of March 2016, Colombia has reported over 50,000 cases of Zika virus disease (ZVD). Methods: We analyzed surveillance data of ZVD cases reported to the local health authorities of San Andres, Colombia, and Girardot, Colombia, between September 2015 and January 2016. Standardized case definitions used in both areas were determined by the Ministry of Health and Colombian National Institute of Health at the beginning of the ZIKV epidemic. ZVD was laboratory- confirmed by a finding of Zika virus RNA in the serum of acute cases. We report epidemiological summaries of the two outbreaks. We also use daily incidence data to estimate the basic reproductive number R0 in each population. Findings: We identified 928 and 1,936 laboratory or clinically confirmed cases in San Andres and Girardot, respectively. The overall attack rate for reported ZVD detected by healthcare local surveillance was 12.13 cases per 1,000 residents of San Andres and 18.43 cases per 1,000 residents of Girardot. Attack rates were significantly higher in females in both municipalities. Cases occurred in all age groups but the most affected group was 20 to 49 year olds. The estimated R0 for the Zika outbreak in San Andres was 1.41 (95% CI 1.15 to 1.74), and in Girardot was 4.61 (95% CI 4.11 to 5.16). Interpretation: Transmission of ZIKV is ongoing and spreading throughout the Americas rapidly. The observed rapid spread is supported by the relatively high basic reproductive numbers calculated from these two outbreaks in Colombia.

Download data

  • Downloaded 998 times
  • Download rankings, all-time:
    • Site-wide: 36,818
    • In epidemiology: 1,963
  • Year to date:
    • Site-wide: 172,330
  • Since beginning of last month:
    • Site-wide: 128,581

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide