Mapping Zika virus infection using geographical information systems in Tolima, Colombia, 2015-2016

Abstract

Objective: Geographical information systems (GIS) have been extensively used for the development of epidemiological maps of tropical diseases, however not yet specifically for Zika virus (ZIKV) infection. Methods: Surveillance case data of the ongoing epidemics of ZIKV in the Tolima department, Colombia (2015-2016) were used to estimate cumulative incidence rates (cases/100,000 pop.) to develop the first maps in the department and its municipalities, including detail for the capital, Ibagué. The GIS software used was Kosmo Desktop 3.0RC1®. Two thematic maps were developed according to municipality and communes incidence rates. Results: Up to March 5, 2016, 4,094 cases of ZIKV were reported in Tolima, for cumulated rates of 289.9 cases/100,000 pop. (7.95% of the country). Burden of ZIKV infection has been concentrated in its east area, where municipalities have reported >500 cases/100,000 pop. These municipalities are bordered by two other departments, Cundinamarca (3,778 cases) and Huila (5,338 cases), which also have high incidences of ZIKV infection. Seven municipalities of Tolima ranged from 250-499.99 cases/100,000 pop., of this group five border with high incidence municipalities (>250), including the capital, where almost half of the reported cases of ZIKV in Tolima are concentrated. Conclusions: Use of GIS-based epidemiological maps helps to guide decisions for the prevention and control of diseases that represent significant issues in the region and the country, but also in emerging conditions such as ZIKV.

Mapping Zika virus disease incidence in Valle del Cauca

“…There is an enhanced number of ZIKV-associated neurological syndromes with 25 cases reported from Valle del Cauca as well one case of acute flaccid paralysis with history of ZIKV infection [10]. Then, public health policies and strategies for integral control of ZIKV in people living, but also in visitors [4][5][6][7][8]13] to those areas, should be considered and urgently implemented; particularly in the capital, Cali, and in the Northern municipalities. In Cali, as well as Valle del Cauca, other arboviruses, such as dengue and chikungunya are also cocirculating [14].…”

“…Use of GIS-based epidemiological maps allow to integrate preventive and control strategies, as well as public health policies, for joint control of this vector-borne disease in this and other areas of the country [4][5][6][7][8][9][16][17][18][19][20][21][22][23][24]. As other arboviruses are co-circulating (dengue, CHIKV and ZIKV), maps of them as well for co-infections will be also needed [16,17].…”

“…These interventions would be even on real time and cost-effective for early control activities [27]. They would also play an important role in the virus spread assessment [4][5][6][7][8][9]13] as in Colombia and its Valle del Cauca department in 2015-2016.…”

“…This enables to make recommendations related to prioritize interventions in population living in those areas as well as in visitors to, or people returning from visiting specific places [4,5]. We have previously developed epidemiological maps for ZIKV in Colombia using geographical information systems (GIS) at high incidence departments, such as La Guajira and Sucre (Caribbean region), Tolima (Central area), Santander and Norte de Santander (Northeastern area) [6][7][8][9]. We have also previously provided GIS-based epidemiological maps for CHIKV in other areas of the country [5].…”

Joint Estimation of Relative Risk for Dengue and Zika Infections, Colombia, 2015–2016

“…Examples for the spatial patterns assessment of Zika risk run from merely descriptive methods to model-based approaches. For instance, in Colombia, descriptive risk maps associating Zika incidence rates with environmental and sociodemographic factors have been produced in the departments of Sucre ( 12 ), Tolima ( 13 ), Guajira ( 14 ), Santander, and Norte de Santander ( 15 ) and in the city of Pereira in the department of Risaralda ( 16 ). Model-based spatial patterns assessment of Zika risk have been developed for the 33 departments in Colombia by using Poisson models for the RR for Zika ( 17 ).…”