Climate change threatens malaria control efforts, WHO warns: 6 mitigation strategies to adopt

Malaria, a mosquito-borne infectious disease, continues to be a major public health concern, particularly in tropical and subtropical regions but while significant strides have been made in recent decades to control and eliminate malaria, a new threat is emerging – climate change. The World Health Organization (WHO) has identified climate change as a growing threat to malaria control efforts, with changes in temperature, humidity, and rainfall patterns influencing the behaviour and survival of malaria-carrying mosquitoes.

Climate Change and Malaria Transmission

In an interview with HT Lifestyle, Dr RR Dutta, HOD and Senior Consultant - Internal Medicine at Paras Health in Gurugram, shared, “Climate change can directly influence malaria transmission by affecting the development and survival of malaria-carrying mosquitoes, such as the Anopheles species. Warmer temperatures can accelerate the parasite's development within the mosquito, increasing the likelihood of transmission. Additionally, changes in rainfall patterns and humidity can alter the availability of breeding sites for mosquitoes, potentially leading to increased vector populations.”

He pointed out, “Studies suggest that temperatures between 22-30°C provide optimal breeding grounds for the Anopheles mosquitoes that carry malaria. Furthermore, changes in rainfall patterns can significantly impact mosquito populations. Increased rainfall can create more stagnant water bodies, ideal breeding sites for mosquitoes. Conversely, droughts can concentrate existing water sources, further amplifying mosquito breeding. The unpredictable nature of these climate shifts makes it difficult to predict malaria outbreaks, posing a challenge for control programs that often rely on seasonal trends.”

The Expanding Reach of Malaria

Dr RR Dutta opined, “Perhaps the most concerning consequence of climate change for malaria is the potential geographical expansion of the disease. Warmer temperatures could allow malaria-carrying mosquitoes to thrive at higher altitudes and latitudes, bringing the disease to regions previously unaffected.”

Implications for Public Health

Highlighting that the impact of climate change on malaria transmission is not uniform across regions, Dr RR Dutta explained, “While some areas may experience an increase in malaria transmission due to climate change, others may see a reemergence of the disease in regions where it was previously controlled. The WHO's annual malaria report for 2023 emphasizes the growing threat of climate change to malaria control efforts, with changes in temperature, humidity, and rainfall patterns potentially leading to increased transmission and disease burden, particularly in vulnerable regions.”

He elaborated, “Climate variability is also expected to have indirect effects on malaria trends through reduced access to essential malaria services, disruptions to the supply chain of insecticide-treated nets, medicines, and vaccines, and population displacement due to climate-induced factors. Existing control measures, such as insecticide-treated bed nets and indoor residual spraying, might become overwhelmed by the sheer increase in mosquito populations and transmission rates. Additionally, changes in malaria seasonality could require adjustments to the timing of control programs, demanding greater flexibility and adaptability.”

The Need for Proactive Measures

To address the challenges posed by climate change to malaria control efforts, Dr RR Dutta suggested some adaptive responses and mitigation strategies that are essential -

1. Strengthening health systems: Ensuring that health systems are resilient and adaptive to the impacts of climate change is crucial. This includes improving access to essential malaria services, strengthening disease surveillance and response systems and investing in research and development for climate-resilient interventions.
2. Promoting climate-resilient agriculture: Agricultural practices that reduce greenhouse gas emissions and promote resilience to climate change can help reduce the risk of malaria transmission in rural areas. This includes sustainable land use management, agroforestry and the promotion of climate-smart agriculture.
3. Community engagement and empowerment: Empowering communities to participate in malaria control efforts and adapt to the impacts of climate change is essential. This includes raising awareness about the risks of malaria and climate change, promoting community-based surveillance and response systems and supporting the development of climate-resilient livelihoods.
4. Public Education on Malaria Transmission: Public education plays a vital role in mitigating the impact of malaria. Educating communities on preventative measures, such as using bed nets, reducing mosquito breeding sites around homes and seeking prompt medical attention if symptoms arise, is crucial.
5. International cooperation: Addressing the global challenge of climate change requires international cooperation and commitment. This includes supporting global efforts to reduce greenhouse gas emissions, promoting technology transfer and capacity building and strengthening international cooperation on health and climate change.
6. Research and New Interventions: The healthcare sector must also look towards the future. Research into new malaria interventions, such as potential vaccines and innovative drug therapies, holds immense promise. While these advancements might still be under development, Paras Hospitals emphasizes the importance of staying updated on such progress and potentially offering these advancements in the future, subject to necessary approvals and regulations.

Dr RR Dutta concluded, “Undoubtedly, climate change presents a complex and evolving challenge for controlling malaria. However, through proactive public health measures, collaboration across sectors, and a commitment to research and innovation, these challenges can be mitigated. The fight against malaria requires not only scientific advancements but also a shift in human behaviour. Climate change mitigation strategies to reduce greenhouse gas emissions are essential for long-term success. Sustainable land-use practices that minimize mosquito breeding grounds are crucial. The challenge we face is significant, but the potential for a healthier future is within reach. By acknowledging the threat posed by climate change, investing in proactive solutions, and fostering collaboration across sectors, we can ensure a world where malaria is no longer a looming threat but a relic of the past.”