Early detection crucial to combat dengue

The recent outbreak of dengue fever has claimed several deaths and incapacitations in Karnataka. Hospitals are flooded with people suffering from the fever and the blood banks are inadequate to keep pace with the rising demand for blood platelets.

Dengue fever is a major health problem in tropical and sub-Saharan regions of the world. It is the most important mosquito-borne viral disease affecting humans. Globally over two million cases of dengue occur annually, and approximately 21,000 deaths are attributable to it.

Transmitted by the mosquito Aedes aegypti, the disease is accompanied by high fever and severe muscle pain. Symptoms include intermittent fever and head ache, pain in the joints, rashes over the body and pain behind the eyeballs. Unless treated immediately, a patient can slip into coma and die within 48 hours.

Children and the elderly are more vulnerable because of their low immunity. The victims are incapacitated for a long time unable earn a living. Dengue disease presents highly complex pathophysiological, economic and ecologic problems.

The lost productivity is an economic loss to the nation.Dengue fever’s recent emergence seems to have a definite correlation with the change in climate. The outbreak occurs with the onset of the south-west monsoon accounting for 60-65 per cent of total rainfall. Epidemics in Karnataka in the last ten years are either waterborne or carried by mosquitoes. Water logging and unsanitary conditions during rainy season, poor waste management systems, ineffective vector control programme, and stagnant water in polluted ponds continue to provide fertile breeding grounds for mosquitoes.
The health system in Karnataka is ill equipped to face the outbreak of epidemics such as dengue fever. The poor disease monitoring systems and defunct Pollution Control Board are adding to its helplessness. Local bodies such as village panchayats and municipalities are failing to maintaining clean surroundings. Erosion of the grassroots-level public healthcare system and the dysfunctional municipal systems that don’t deal effectively with waste-disposal, are the main reasons for  outbreak.

Vector borne diseases are on the rise and prevention is the best solution. Dengue fever is of particular concern since there is no curative treatment for it. As no vaccines are available, reducing the habitat and the number of disease causing mosquitoes and limiting exposure to bites are considered to be the best preventive strategies. Careful local assessment of the ecology of Aedes aegypti larvae and pupae can help target environment management and other control measures.

Integrated Vector Control Programme of the WHO suggests the following:

a) Advocacy, social mobilisation and legislation to ensure that public health bodies and communities are strengthened
b) Collaboration between the health and other sectors
c) An integrated approach to disease control to maximise use of resources
d) Evidence-based decision making to ensure any interventions are targeted appropriately
e) Capacity-building to ensure an adequate response to the local situation.”

Preventive measure
Eliminating the habitats of Aedes aegypti is considered to be the best method of controlling it. Emptying water containers and applying insecticides or biological control agents to stagnant water helps in eliminating the disease causing mosquitoes. Since the application of insecticides can generate negative health effects, reducing stagnant water collections through environmental modifications is the ideal method. Wearing clothes that fully cover the skin, using mosquito nets and applying insect repellents are all effective measures. People should be encouraged to clean their fridge trays, pots, flower vases and other places where clean water gets accumulated.

The government has to organise disease prevention camps and visits by health professionals to the areas severely affected by the fever. The state should have a system to maintain dengue surveillance data. It should include incidence, hospitalisation rates, and deaths by age groups. The focus should be on early detection and prediction of dengue outbreaks.

Since the disease is caused by poor health awareness, public campaigns and mass-based preventive methods are the best ways to tackle it. Revival of primary health centres can help in such an approach. It is time for the state health system leadership to revive the public health delivery with a focus on cost effective methods of preventive care. Accelerating the already delayed anti-dengue measures is the need of the hour.
(The writer is professor of health economics at Christ University, Bengaluru)