By Bhabna Banerjee, Inside Climate News
Health professionals are issuing warnings about the impact of climate change on the spread and evolution of infectious diseases. Dr. Angelle Desiree LaBeaud, a physician-scientist, epidemiologist, and professor in the Division of Pediatric Infectious Diseases at Stanford University’s School of Medicine, highlighted the growing connection between climate change and vector-borne diseases in an interview with ‘Inside Climate News’.
Dr. LaBeaud emphasized that in Kenya, there is a significant transmission of these infections, but much of it goes unnoticed. She stated, “In Kenya, where I have direct experience, we have observed a substantial transmission of these infections, yet many cases remain undetected. Outbreaks occur, but often go unrecognized. People fall ill without understanding the cause of their illness.”
Dr. LaBeaud has highlighted the implementation of various initiatives aimed at improving the current situation in Kenya. She emphasized the importance of projects that connect climate variables with disease outbreaks to provide policymakers with early warnings, enabling them to allocate resources effectively.
“Several projects are working to link climate variables with disease outbreaks to provide policymakers with advanced notice so they can allocate resources accordingly. But that’s not easy. We helped develop an early warning system for policymakers in Kenya, but even with good forecasting, if you don’t have the resources to respond, it’s incredibly challenging.”
According to Dr LaBeaud, infections—particularly vector-borne diseases—are increasingly re-emerging and emerging in new areas around the world for a lot of different reasons: Climate change is definitely part of that, with rising temperatures and more extreme weather events like floods and droughts. But the way we live our lives and interact with the environment also plays a huge role,” she says.
“The major categories of infectious diseases that are impacted by climate change are respiratory, waterborne, and vector-borne diseases. The convergence of crises—the climate crisis overlapping with the pollution crisis creates the intersection between air pollution and respiratory diseases, and then infectious diseases more broadly, all layered on top of a changing climate.
“When it comes to waterborne and foodborne diseases, the link to climate change is even more direct. As temperatures rise, you create more favorable conditions for bacteria and other pathogens to multiply. They thrive in warm environments—soil, water, contaminated areas—so warming can increase their abundance.
“When flooding happens, those pathogens that were sitting in soil or contaminated areas can get swept into the water supply. They move around and people end up exposed, especially during crises when sanitation and access to clean water break down,” Dr LaBeaud explained.
According to Dr LaBeaud, climate plays a really significant role in the spread of infections such as dengue, chikungunya, Zika and yellow fever that are transmitted by the Aedes aegypti mosquito: “This mosquito loves the heat. So as global temperatures rise, she thrives.” In recent years, there has been an increase in the outbreak of these diseases in Kenya, mainly in the North Eastern region and coastal areas.
“Extreme weather events are also a big factor here. Aedes mosquitoes need water to complete their life cycle—from egg to larva to pupa, it all happens in water. When floods occur, all the discarded plastic and trash lying around fill with water and become the ideal breeding ground for mosquitoes.
“What is interesting is that these diseases aren’t just associated with floods—they’re also linked to droughts. In many parts of the world, people don’t have safe, reliable access to clean water, especially during drought conditions. So, they store water in containers that aren’t properly sealed or protected, which can also become the perfect breeding sites for mosquitoes,” she expounded.
She says there is a need for environmentally conscious, thriving communities that live sustainably to make communities healthier and environments more resilient. She also expresses the need for early warning systems, effective treatments, cleaning up the environment, educating people so they understand why they’re doing it, and creating a sense of collective responsibility.
“When you clean up your environment, you’re not just reducing mosquito breeding sites and vector-borne disease, you’re also likely reducing things like rodent infestations and food and waterborne illnesses in the neighborhood,” she advises.
Dr LaBeaud also calls for the protection of forests as a way of protecting against infectious diseases: “On the topic of emerging infections, there’s this huge link between deforestation and disease. As humans move closer to forest edges and fragment natural habitats, we come into contact with mosquito species—and the pathogens they carry—that we’ve never encountered before.
“In pristine, balanced ecosystems, nature regulates itself. You have predators that eat mosquitoes. Things are kept in check. But when we disrupt those systems, we lose that balance… These infections don’t just impact us, they affect animals and ecosystems too. We need to think about how we can use nature-based solutions to promote health for humans and all the other living beings that share this planet.”
This article originally appeared on Inside Climate News https://insideclimatenews.org/news/26042025/climate-change-shifting-spread-of-infectious-disease/ a nonprofit, non-partisan news organization that covers climate, energy and the environment. It has been edited to suit the Kenyan context
