Spatiotemporal analysis of dengue outbreaks in Samanabad town, Lahore metropolitan area, using geospatial techniques

Dengue is endemic to Pakistan with its usual peak incidence in the post-monsoon period. In the last decade, dengue outbreaks have occurred in major urban areas particularly Karachi and Lahore, affecting large numbers of people. This study is an attempt to analyze the spatiotemporal variation of dengue fever (DF) in Samanabad town, Lahore metropolitan area. The study is based on secondary data, acquired from concerned government departments. Point level geo-coding is used to transform the relative location to the absolute location using Google Earth, and Global Position System (GPS) is used to validate the geo-coded location. Geographic information system (GIS) has been used to perform spatial analysis. It has been found that temporally DF prevalence varies from month to month and year to year. Major outbreak was observed in the year 2013 with more than 900 confirmed DF cases. Rainfall, temperature, and humidity have played a central role in outbreaks. The land cover pattern and population density further intensified the outbreak. Spatially, the number of DF incidence was high in those localities where the entire land is built-up and with little/no green space areas. Analysis reveals that DF is still a major threat to the area as socioeconomic and geographic conditions favor vector breeding and transfer of disease from one person/place to another. This study presents useful information regarding spatiotemporal patterns of dengue outbreak and may bring the attention of public health departments to formulate dengue-combating strategies. The methodology is general for spatiotemporal analysis and can be applied to other infectious diseases as well.