Rising Dengue Cases Linked to Climate Change: Experts Highlight Vaccination as Crucial Defense

Climate change results in unpredictable weather patterns that can lead to alarming situations. Data from the World Health Organization (WHO) shows that healthcare is one of the sectors significantly impacted by climate change. As a result, the geographic range of several vector-borne human infectious diseases is expected to expand.

“Currently, dengue is on the rise, with climate change being a significant factor contributing to the increased disease transmission. The most critical factors associated with dengue are temperature, rainfall, and relative humidity,” said Dr. Bayo Segun, WHO representative, during his presentation at the first Dengue Summit held in Manila.

The president of the Philippine Medicine Association (PMA), Dr. Hector Santos,  underscored the potential rise in dengue cases in the coming months, attributing it to climate change and urging the public to be vigilant. He emphasized the need for collaboration among key stakeholders in strategically preparing to combat dengue.

“The rising number of dengue cases serves as a stark reminder of the urgent need for a unified front in the battle against this disease,” Santos stated, reaffirming the commitment to “Zero Dengue Death by 2030” in alignment with the United Nations’ Sustainable Development Goal 3.

The 1st Dengue Summit, a collaborative effort led by the Philippines Medical Association (PMA), the Philippines College of Physicians (PCP), and the Philippine Pediatric Society, Inc (PPS), aims to galvanize a national action against the urgent public health threat posed by dengue fever.

The Dengue Summit aims to drive transformative change through enhanced collaboration among key stakeholders. While current vector control methods have shown its effectiveness, the summit emphasized the crucial role of integrating innovative interventions such as vaccination into a holistic dengue management framework alongside robust surveillance systems, enhanced healthcare infrastructure, and active community engagement to decisively combat dengue in the Philippines.

The role of vaccination in achieving zero dengue death

Health Secretary Ted  Herbosa said that reaching such a goal was  “ambitious yet within our grasp,” provided that there would be collaboration and concerted action from government agencies, healthcare providers, community organizations, and the private sector.

“The journey to achieving zero dengue deaths by 2030 will not be easy, but it is a journey we must undertake with determination and unity. Let us be inspired by the progress we have made and be motivated to push further, innovate more,  and collaborate better. Together, we can create a future where dengue is no longer a threat to every Filipino,” he said via recorded message.

“I want to add something very important about management, surveillance, capacity, and communication. We now have a new tool to fight dengue: a vaccine. Dengue is now a vaccine-preventable disease. It is crucial to communicate to all healthcare professionals and the public about the safety and efficacy of the vaccine, promote its use, and incorporate it into the national immunization program,” noted Dr. Renato de Avila Kfouri, President, Department of Immunizations, Brazilian Society of Pediatricians.

Brazil has exceeded its worst-case forecast for dengue cases this year, with a record of over 5 million infections. This increase is attributed to the effects of El Niño,  which has led to higher temperatures and changes in wet and dry weather patterns , creating favorable conditions for mosquito breeding. Similarly, the Philippines is facing a rise in dengue cases as it braces for the onset of La Niña. Data from the Department of Health shows a concerning increase in reported dengue cases compared to the previous year, with 59,267 cases from January 1 to May 4, surpassing the figures for the same period in 2023 of 45,722 cases.

“The parallel between the weather trends and escalating dengue cases in Brazil and the Philippines serves as a cautionary tale about the potentially devastating impact of dengue fever in the Philippines. This comparison highlights the urgent need for immediate and innovative actions to address the rapidly growing threat of dengue disease in the country,” highlighted Dr. Dr. Imelda M. Mateo, President of Philippine College of Physicians.

Lessons learned and best practices

“Dengue remains challenging in Indonesia. However, dengue vaccine is one of the important ways to reach the goal of zero dengue death in the country. A comprehensive evaluation of the national strategy of dengue prevention should be planned,” said Dr. Eggi Arguni, Pediatric Consultant, Faculty of Medicine, Public Health and Nursing Universitas Gadjah Mada.

According to Philippine Foundation for Vaccination Executive Director Lulu Bravo, the dengue vaccine, QDENGA, had been licensed in Indonesia last year. The Philippines’ other neighbors – Thailand,  Malaysia, and Vietnam – have also approved the vaccine.

“As a vaccine investigator, I will assure you the safety of QDENGA because we’ve been doing it for eight years now, since 2016,” she said. “I did a study on the vaccine, and we did not see safety signals at all and it can be given to those who have not had previous Dengue. Which is what is different from the previous first-generation Dengue vaccine – that it was meant to be given only to those who had previous Dengue,” she added.

Infectious disease expert Dr. Rontgene Solante supports this, believing that Filipinos are now more prepared to accept a new dengue vaccine compared to previous years. He noted that the COVID-19 vaccination efforts have particularly taught the public an important lesson about the significance of vaccination.

“I would say most likely we have matured in terms of vaccination because of our experience with COVID-19,” said Solante, who was the previous president of the Philippine College of Physicians.

As the summit concluded, stakeholders reaffirmed the need for governments, public health agencies, researchers, and communities to collaborate in prioritizing the research and development of new tools and strategies. Investing in vector control technologies, digital health solutions, and innovative tools like next-generation dengue vaccines is essential to strengthening our defenses against dengue and reducing its impact on vulnerable populations.

The 1st Dengue Summit, organized by the Philippine Medical Association, the Philippine College of Physicians, and the Philippine Pediatric Society, was supported by Takeda Healthcare Philippines, Inc. and managed by Rise Above Now Business Consulting Group (RAN BCG+).