Dengue Epidemic : Causes and Consequences

The government epidemiology unit reports that the dengue cases have already exceeded the 20,000 mark in the first six months of 2014. If the trend continues in the next few months, it can exceed the 2009 figure of 32, 7000. Nearly 60% of all cases are reported from the western province, while the other high concentrations are in larger urban centres in other parts of the country like Ratnapura, Kurunegala, Kandy, Batticaloa, Jaffna and Galle.



The above figures show that Dengue is very much an urban phenomenon, associated with high population and residential density and poor environmental management. The Western province today has nearly one third of the country’s population. This is not surprising because the province also accounts for over 50% of the country’s wealth. People naturally flock to this region because wealth is concentrated here.



It is true that the incidence of dengue follows the pattern of annual rainfall. The epidemic usually coincides with the rainy season. On the other hand, if we blindly follow this logic, we should simply expect a dengue epidemic to follow the rainy season, a natural course of events! But, a dengue epidemic is a serious matter and cannot be simply treated as a mere natural phenomenon. It costs human lives. It puts enormous pressure on health institutions. It poses a grave threat to the lives of thousands of people. It disrupts the social and economic life of families affected by the disease, etc. So, not many people want to accept it in a fatalistic manner.



The above situation naturally compels us to explore ways and means of arresting the worsening trend. How can we prevent periodic dengue epidemics? In order to find an answer to this question, we should look at the statistics more closely, in terms of their historical trends and spatial patterns. As I already mentioned, statistics closely correspond to the trend in internal population mobility in the country over time. Moreover, there is a clear correlation between population density and the incidence of dengue.
But, the factors that create conditions conducive for the spread of the disease are not obvious and need to be identified in order to find a way to respond to the epidemic. The present tendency on the part of the authorities to simply blame the people for the spread of the disease prevents us from identifying underlying factors that are actually at the root of the epidemic. This does not mean that we should not take measures to educate and encourage citizens to be civic minded and environmentally conscious.



As mentioned earlier, the extremely high concentration of population in and around Colombo has resulted in a built environment and settlement pattern that are highly conducive for the spread of dengue. Increasing demand for land in the Colombo metropolitan region has led to an unprecedented rise in land values which are beyond the means of a large majority of people.
This has also led to land fragmentation and the spread of low income disadvantaged settlements everywhere. Buildings have come up everywhere, often obstructing public infrastructures like canals, open spaces, access roads, railway lines, etc.
 Most of the people who have migrated to the western province from other parts of the country in recent years are low income persons and families in search of livelihoods.



They mostly engage in informal sector activities like three wheeler driving, pavement hawking, construction work, personal services, private security and retail trade. Given the fact that there is no major publicly or privately funded low income housing programme in the country, most of these people live in low income settlements which are characterized by extreme congestion, the lack of open space, poor and irregular constructions, inadequate facilities for drainage and waste disposal, etc.
Given the low and irregular incomes of the vast majority of people living in the Colombo metropolitan region and other urban centres across the country, one cannot expect a different pattern of human settlement. In more developed Asian countries like Singapore, Malaysia and Taiwan, the situation is different largely because more carefully planned low income housing has prevented the kind of haphazard development that has taken place in this country.



Another major issue that has a bearing on the spread of dengue is the poor physical infrastructure in low income areas.
Proper storm water management is a near impossibility in urban areas due to poorly constructed and poorly maintained minor roads, canals and drains. This is the general picture that one finds in almost all urban areas, not just in the Colombo metropolitan region. After each spell of rain, water gets collected in pot holes, dilapidated drains and unevenly paved footpaths in almost all urban neighbourhoods.



Local authorities are incapable of doing much to address these issues. In the case of local authorities, the priorities are different; they want to build supermarkets, office buildings, etc., to collect revenue rather than develop and implement systems for the proper management of the built environment. As is well known, the local councils receive only a small fraction of the state revenue. This is grossly inadequate to meet the cost of a much needed environmental improvement programme within their jurisdictions.



Given the above state of affairs, it is unrealistic to expect a significant change in the incidence of dengue in the near future, unless a major programme of integrated environmental management is introduced in order to revamp low income settlements and streamline storm-water management in the Colombo metropolitan region and beyond. Whether the necessary resources could be mobilized to do so is a question that only the relevant authorities can answer. Meanwhile, the authorities will continue to blame the people for the worsening dengue epidemic in the country, for not doing enough in their neighbourhoods to prevent the spread of the disease that many of them suffer from. On the other hand, the cost of the epidemic is mounting, not just for the victims but for the entire country. While the quality of life of the people living in affected areas is significantly undermined by the threat of dengue, those who are infected and their families are naturally traumatized by the life threatening nature of the illness. Moreover, the epidemic is not good advertising for the tourist industry as some may think twice before travelling to the country in the mildest of an epidemic.