Why we need comprehensive dengue management to achieve zero deaths

In recent years, dengue fever epidemics in South and Southeast Asian countries such as India, Bangladesh, Thailand, Malaysia, Indonesia, Vietnam, Singapore and the Philippines have become more severe than usual ahead of the traditional peak season.

As climate change alters epidemiological trends, the number of cases in non-endemic countries is also likely to increase in the coming years.

Changing weather patterns are leading to the emergence and re-emergence of climate-sensitive diseases such as dengue fever, which has seen a 30-fold increase in global cases over the past 50 years.

Dengue fever not only impacts public health but also causes an economic burden of up to US$8.9 billion globally. Therefore, a comprehensive strategy with targeted measures is needed to manage dengue fever to achieve zero mortality by 2030.

Together with existing surveillance and vector control measures, a safe and effective vaccine may play an important role in reducing the burden of dengue. Importantly, the efforts of public and private sector stakeholders are critical to prevent, manage and control this health threat.

How dangerous is dengue fever?

Dengue fever is a viral infection caused by Aedes aegypti Mosquito and dengue infections range from subclinical illness to severe flu-like symptoms.

Some patients develop severe dengue, with severe bleeding, organ damage and plasma leakage – the leading cause of dengue hospitalization and death in adults and children.

Additionally, as infection demographics shift toward older age groups, these individuals have higher rates of comorbidities, resulting in more severe illness and mortality.

The prevalence of dengue fever has increased dramatically, and first outbreaks have been reported in countries where it had not previously been endemic. Without effective solutions, nearly half of the world’s population is at risk of dengue fever.

Closer to home, there were more than 650,000 dengue cases in Southeast Asia in 2019, and the incidence rate increased by 46% between 2015 and 2019. Scientists speculate that factors such as urbanization and climate change have contributed to dengue becoming a global epidemic. The fastest spreading mosquito-borne viral disease.

In fact, with an estimated 100 million cases annually, dengue causes more illness and death than any other disease caused by arboviruses.

Large-scale dengue outbreaks can quickly overwhelm health systems, and the annual economic burden of dengue in Southeast Asia is estimated at US$950 million, higher than other infectious diseases including upper respiratory tract infections and hepatitis B.

Meeting the challenge of dengue fever

Dengue is a complex disease because the virus has four serotypes, each of which interacts differently with antibodies in the human body.

A person may develop immunity after being infected with one of the dengue serotypes but remain susceptible to infection by the other three serotypes. In addition, individuals are at increased risk of developing more severe dengue fever after a second infection with a different dengue serotype.

Tackling dengue is a difficult task because development and research on all four serotypes is complex and resource-intensive. Dengue has also historically received limited investment because the disease burden was previously limited to underserved areas.

There is currently no universal treatment for dengue fever, but common prevention methods exist, including personal protection, chemical control, and environmental management. Aedes aegypti

mosquito.

World Mosquito Project uses a method to create mosquitoes that carry naturally occurring bacteria Wolbachiaand release them into the environment. This bacterium makes it difficult for viruses such as dengue fever to replicate in mosquitoes and reduces the risk of the virus spreading to humans.

While existing dengue methods work in controlling dengue, they are only partially effective. As we increase the utilization of vector control strategies, the concurrent decline in population immunity poses a major challenge to efforts to further control the disease.

The situation is similar to the Singapore paradox, where declining levels of immunity against dengue fever lead to increasingly frequent outbreaks.

We must consider population immunity in the context of integrated dengue management, and vaccines will be a key solution to this challenge.

Vaccination, along with other pillars such as surveillance, robust healthcare systems and sustainable community awareness, were widely recognized at this year’s Asia Dengue Summit, where a comprehensive approach is expected to help eliminate the growing global burden of dengue.

Towards dengue eradication

Despite the challenges of developing a dengue vaccine that protects against all four virus serotypes, safe and effective vaccines have been developed.

Earlier this month, the World Health Organization’s vaccine expert group SAGE recommended that vaccination be considered in settings where dengue disease burden is high and transmission intensity is high.

One of the vaccines has recently been approved in more than 30 countries, and the other is undergoing phase 3 clinical trials. It is expected that governments in South and Southeast Asia will provide a safe and effective vaccine within the next year and consider launching vaccination campaigns to the public.

To complement vaccine innovation, public health communication about the benefits of dengue vaccines is critical to combating any vaccine hesitancy, misconceptions and fears. The COVID-19 pandemic has shown us the negative impact of misinformation, which contributes to widespread distrust in the safety and effectiveness of vaccines.

Lessons can be learned and applied to the introduction of dengue vaccines, including the importance of working with stakeholders and health authorities to ensure evidence-based content is used to promote educational trust in public health agencies.

This is critical to ensuring the successful rollout of the vaccine and preventing the spread of misinformation. We need to learn from these events to ensure continued confidence in new interventions.

At the heart of the dangers of dengue is complacency in taking regular action to break the dengue transmission cycle. However, we should not lose hope of preventing future outbreaks in our region.

The path to zero dengue deaths may seem far away, but together we can start making progress towards this goal.

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Written by

Dr. Wu ZhumingHead of Medical Affairs, India and Southeast Asia, Takeda Pharmaceuticals

Professor Tiki PangastuCo-Chairman of Asia Pacific Immunization Alliance, Visiting Professor of Yong Loo Lin School of Medicine, National University of Singapore

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This article was originally published by world economic forum November 1, 2023.