Our Environment and World Malaria Day 2025

By – Dr. N. Munal Meitei
World Malaria Day is observed on April 25 since 2008 to bring global attention to an end to malaria and encourage action to reduce suffering and death from the disease. Through its 2025 theme, ”Malaria Ends with Us: Reinvest, Reimagine, Reignite,” WHO emphasizes the need for renewed commitment, innovative strategies and sustained investment in the fight against malaria.
According to WHO’s latest report, there are an estimated 263 million cases and 597000 malaria deaths worldwide in 2023and 67% of affected are children under five, that’s 1320 dead per day. This represents about 11 million more cases in 2023 compared to 2022 and nearly the same number of deaths. Approximately 95% of the deaths occurred in the developing countries, where they are still lack of services needed to prevent, detect and treat the disease.
In 2022, India accounted for a staggering 66% of malaria cases with Plasmodium vivax, contributed to almost 46% of cases in the country. Despite a 55% reduction since 2015, India being the most populous country remains a significant contributor to the global malaria burden. The country faced the surge in malaria cases in 2023 which linked to the unseasonal rainfall.
Malaria cases in Manipur have significantly decreased in recent years. While there were over 200 official cases in 2015, the number dropped to 19 in 2021. Manipur has been considered a candidate for being the first state or union territory in the country to reach zero malaria cases, although it didn’t achieve this. While the state has fewer cases compared to neighboring states, health experts still caution that outbreaks can occur anytime including the challenges from dengue and Japanese encephalitis etc.
The 2023 World malaria report delves into the nexus between climate change and malaria. Changes in temperature, humidity and rainfall can influence the behaviour and survival of the malaria-carrying Anopheles mosquito. Extreme weather events, such as heat waves and flooding, can also directly impact transmission and disease burden. Catastrophic flooding in Pakistan in 2022, for example, led to a five-fold increase in malaria cases in the country.
Scientists have described the malaria as involving a complex interplay between humans, mosquitoes, the plasmodium and the Environment. Data collected over recent decades has shown that changes in temperature, rainfall, humidity and other climatic conditions have a great impact on important factors that dictate the transmission of malaria, such as the lifespan of the mosquito and the development of malaria parasites in the insect.
The rising in temperature and environmental changes accelerate the distribution of mosquitoes and mosquito-borne diseases. The warmer climate is helping to proliferate the mosquito population at higher altitudes and other geographical areas as well as the risk of transmission rates by adjusting the growth cycle of the parasite and allowing it to develop faster. On the other hand, droughts can also favour the mosquito by converting even the rivers, lakes and ponds into the optimal breeding sites.
Environmental factor plays a key role in malaria intensity and seasonality of the disease. Like chess, malaria is played with a few pieces, but is capable of an infinite variety of situations. The triad human–vector–parasite exists within and interacts with the environment, resulting in a variety of unique transmission requiring a tailored package of control interventions.
In this world of resource scarcity, improving our environment is essential for malaria control. To control the malaria, more funding should be prioritized for the highest-risk populations and countries. Investment in innovation, research and development has played a critical role in reducing the global malaria burden to achieve the malaria cases and deaths to at least 90% by 2030, the global target.
Climate-based factors, temperature and precipitation, are the primary environmental determinants of malaria. The extrinsic development of the parasite is constrained within a certain temperature range, extremely high temperatures are likely to produce smaller and less fecund mosquitoes and increasing temperatures reduce the time for mosquito maturation from larva to adult and increase the feeding frequency. Recent models indicate that malaria transmission is constrained to temperatures between 16°C and 34°C, with optimal transmission at 25°C.
The presence of natural predators of mosquito larvae can contribute to control the population size of malaria vectors, depending on the physicochemical properties of the water habitat. Another important aspect is poverty, as the disease get higher risk with the houses without screens, doors and/or windows. Malaria also concentrated in remote areas and/or among highly mobile or hard-to-reach populations, including forest goers, migrants, indigenous people, military and refugees.
Better environmental management benefits go beyond malaria and are expected to reduce the incidence of dengue, lymphatic filariasis, yellow fever and other diseases. Thus, by promoting a healthier environment, we are directly benefited from vector borne diseases.
However, the adoption of environmental strategies demands local knowledge and expertise. One study estimated that with the cost of saving one life by cutting down on carbon, 78,000 lives may be saved annually by using mosquito nets, environment safe sprays and subsidies for effective therapies.
Realistically, it is probably the case that most malaria control programs do not have the proper knowledge and expertise to effectively account for the local environment in control efforts and maybe do not even have comprehensive entomological information. Thus, filling in these gaps is imperative and the task could be better accomplished by fostering an integrated collaboration between the health workers, donors, the industry, academia, civil societies, NGOs and different sectors of the government.
Malaria is an acute febrile disease and number one enemy for the world today. The disease knows no national boundaries. But malaria is a preventable and treatable disease though it has a devastating impact on the health and livelihood of people all over the world. Effective vector control along with a better environment are crucial to prevent and control the transmission of the malaria. To ensure a healthier and more prosperous future for all, let’s protect our environment for a malaria-free world.
(The author is Environmentalist, presently working as DFO/Chandel. [email protected])