[Answered]The spread of dengue in India has been related to unplanned urbanisation, changes in environmental factors, and a host of other factors. Elaborate.

Dengue is a major public health problem in India. It is a tropical disease caused by the dengue virus through mosquitoes bite. For the past ten years, the number of dengue cases has gradually increased in India. The spread of dengue is due to various factors especially due to unplanned urbanisation and climate change.

Factors responsible for spread of dengue in India:

1. Unplanned urbanisation: As more people move to cities, human-mosquito contact increases contributing to risk of infection. Urbanisation, poor town planning, and improper sanitation are the major risk factors for the multiplication of such mosquitoes. The open sewerage, improper handling of wastage, urban slums, open drains are providing breeding ground for dengue.
2. Climate change: Recent studies have shown that seasonal mean temperature in India has increased significantly over the past years. Slight increases in temperature increase the dengue risk by increasing the mosquito development rate and the virus, thereby increasing the rate of transmission.
3. Poor control measures: Inadequate vector (mosquito) control measures have created favourable conditions for dengue virus transmission and its mosquito vectors. Lack of proper planning to control the vector has led to the spread of dengue. Lack of funding, interrupted fumigation campaigns, and poor management of mosquito eradication programs contribute to the mosquito resistance.
4. Favourable climate: Dengue is a tropical disease that occurs in the countries around the Equator. Hot weather, monsoon and intermittent rainfall favour the sustenance of the vector transmitting the dengue virus.
5. Lack of manpower: The number of skilled workers available for preventing spread of dengue is low. Delhi and Mumbai have 1,260 and 895 employees per 100,000 population respectively vis-a-vis New York’s 5,338 and London’s per 100,000 population respectively. Many posts in government departments remain vacant. Due to this deficiency of manpower, active surveillance against dengue is not being done in India.
6. Under-reporting: Dengue cases are often under-reported due to political reasons and also to avoid spreading panic among the common people. This increases the risk of dengue spreading.
7. Lack of coordination: There is a lack of coordination between the local bodies and health departments in the delivery of public health measures. This leads to an unplanned approach to deal with the dengue epidemic.

 Some measures to prevent spread of dengue:

1. Disease surveillance: Effective surveillance of dengue cases is essential to detect outbreaks to initiate timely and effective control measures. Singapore uses one successful model of mapping and analysing data on dengue, using Geographical Information System (GIS). This involves mapping the streets with dengue cases for vector densities.
2. Strengthening healthcare system: Dengue mortality can be reduced by implementing early case detection. Health services must be strengthened to cope with dengue outbreaks. Training health personnel at all levels of the health system is important.
3. Effective Planning: An effective plan should be prepared on how to tackle any outbreak. It is an important element of the overall strategy to prevent dengue spread. The plan should include all the stakeholders.
4. Effective vector control measures: Effective vector control measures are critical to prevent dengue outbreak. Preventive and vector control interventions like fumigation, awareness campaign, cleanliness drive etc. is needed with an aim to reduce dengue transmission. The integrated vector management approach to vector control as promoted by who should be adopted.
5. Coordination: Dengue prevention and control needs an effective inter-sectoral approach. It requires coordination between the the Ministry of Health) and other relevant ministries and governmental agencies, the private sector, nongovernmental organizations and local communities.

Dengue is endemic to India. An integrated approach is needed to tackle the epidemic. Various causal factors must be controlled. Swachh Bharat mission is important to prevent dengue and must be used to raise awareness about dengue. Without collaborative efforts, fighting the dengue epidemic is not easy.