Tackling the growing disease burden of dengue across the country

Dengue has become a significant public health concern in India, driven by factors such as an increased concentration of population across specific pockets, rapid urbanisation, internal migration patterns, inadequate wastewater management, and challenges in the existing disease control measures which lack the ability to predict outbreaks.  India has witnessed a twenty-five-fold rise in reported cases since 2010, with 94,918 cases reported until September 2023 (1) highlighting the growing concern around dengue and the escalating health challenges the disease poses. This surge can be associated with climate change increasing both the temperature and frequency of heavy rainfalls, promoting mosquito activity and expanding their geographic range. (2)

The World Health Organization (WHO) in its global overview of dengue published in May 2024, stressed improving detection, with strengthened global surveillance and monitoring temporal trends and disease incidence through its Global Dengue Surveillance Dashboard (3). Such approaches, driven by public-private partnerships and robust community engagement replicated at local and national levels can lead to sustainable public health responses to combat the rise of dengue. The Pune Knowledge Cluster (PKC), established under the Office of the Principal Scientific Adviser, has proactively responded to this growing threat with several key initiatives. These include mapping dengue incidence to identify hotspots and trends, conducting dengue whole genome sequencing to understand the virus’s genetic variations, and implementing training programs for health workers. These programs focus on the detection of dengue, recognising its symptoms, and understanding the impact of climate change on the disease’s spread. Additionally, PKC also developed a comprehensive policy brief to enhance the capacity of public health systems to manage and mitigate the effects of dengue outbreaks effectively.

Dengue is generally known to follow a pattern associated with the monsoon season; however, empirical evidence now highlights the drastic increase in incidence rates across India, even during the pre-monsoon period. Studies conducted during 2012-2014 estimated that India had close to 5.8 million cases, highlighting the underreporting of cases as the public surveillance system reported only 1 in 282 cases. The gross economic costs calculated exceed over 1.1 billion USD, of which 49 per cent were associated with direct medical costs and 51 per cent to the loss in productivity (4). As the incidence of dengue continues to escalate due to climate change, the associated economic costs will also increase substantially. Strengthening disease surveillance and improving vector control measures are crucial to mitigate this growing burden.

However, the management of disease reporting and data management in India remains extremely complex due to a preexisting hierarchical structure, which often leads to the underreporting of cases. The dengue cases are first reported by Primary Healthcare Centres (PHCs) or Community Healthcare Centres (CHCs). They are then reported at the state level by the National Centre for Vector Borne Disease Control (NCVBDC). Parallelly, the Integrated Disease Surveillance Program (IDSP) operates with its own structures and reporting mechanism that differs from NCVBDC. The existence of a dual reporting system complicates surveillance and leads to underreporting due to the lack of integrated testing channels and limited interaction between the various autonomous bodies managing surveillance.

To improve dengue surveillance and reporting in the country, a multi-faceted approach is essential. Due focus must be provided to develop early warning systems to identify specific disease hotspots within a city and locale. This can be achieved by integrating real-time data tracking of positive tests with long-term retrospective data from private hospitals and clinics. Such integration will enable researchers and government surveillance systems to build reliable predictive models of disease incidence. Additionally, consolidating dengue data for surveillance should also include factors like social, behavioural and environmental data such as climate, urbanisation, and human activities. This comprehensive data integration will enhance predictive models of dengue incidence and severity. Moreover, incorporating dengue research into the public health ecosystem would foster better information exchange and synergy to combat the disease. 

Public-private partnerships are crucial to establishing a successful disease management ecosystem, strengthening the health infrastructure and facilitating healthcare provision. This will aid India’s private health sector in identifying micro-clusters and interrupt the transmission of vector-borne diseases (5).  Such a mechanism would mandate all entities within public health systems as the bulk of dengue detection occurs outside of the government surveillance system, i.e. private laboratories. This integration will aid in accurately mapping the true disease burden for a reliable prediction system. The correlations associated with presumptive, suspected, and confirmed cases can help track disease progression in patients with symptoms. 

Well-trained personnel are one of the most indispensable aspects of disease outbreak management. Hence, emphasis has to be placed on departments to prioritise capacity building and ensure quick identification and pre-emptive measures are in place targeting disease incidence reduction.  As dengue is a seasonal disease, staffing needs can be identified in advance of an outbreak based on empirical data. In tandem, implementing dengue awareness campaigns and providing at-risk populations with accurate information and prevention strategies to aid communities in their mitigation efforts is also required.

Addressing the rising incidence of dengue requires a coordinated and comprehensive approach that includes interdisciplinary studies to help develop resilient predictive capacities. It is necessary to build and replicate a model of perpetual surveillance and dengue detection at local and state levels to enable effective public health response. Lastly, it is imperative that policymakers, healthcare professionals, and the public collaborate and implement the policy recommendations for effective dengue control.

References: 

1.https://ncvbdc.mohfw.gov.in/index4.php?lang=1&level=0&linkid=431&lid=3715

2. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021GH000477

3. https://www.who.int/emergencies/disease-outbreak-news/item/2024-DON518

4.https://www.sciencedirect.com/science/article/pii/S1201971219300219#:~:text=India%20had%20about%2053%20million,%2C8%25%20of%20total%20costs.

5. https://www.financialexpress.com/business/healthcare-public-private-partnership-will-help-effectively-address-mosquito-menace-2789847/