Arjun VK Sharma
The threat of climate change brings to mind a particular scene. Smoke rising from a burning forest. A suffocating heat clinging to the warped asphalt of a dense street. Glaciers crashing into the rising sea. Another scenario would be equally terrifying, but it’s hard to imagine. It is the separation of the virus from the animals that have played blind hosts for the invading humans.
For years, scientists have warned us of an unsettling reality. Climate change is increasing the likelihood of a pandemic in our collective future.
Much like climate change’s impact on our environment, its impact on our health appears to be insidious. Considering we’re almost three years under COVID-19 and after the recent monkeypox outbreak, the changing climate puts us closer to thousands of potentially devastating viruses.
Changes in temperature and precipitation shift the geographic range of animals such as mosquitoes, ticks, birds and small mammals into the vicinity of humans. Storms and floods drive people off the land and bring them closer to disease-spreading animals. This means more and more contact with wildlife, the organisms they carry, and the diseases that come with them.
The recent floods in Pakistan after an unprecedented monsoon season are a striking example. The country is already experiencing an increase in cholera caused by the bacterium Vibrio that pollutes water sources. Since then, floods have disrupted vaccination, medical care and disease surveillance strategies vital to controlling the epidemic. Where large bodies of water are stagnant, mosquitoes harboring dengue and other viruses and parasites such as malaria thrive and infect people with them. Pakistan’s looming waterborne health crisis is feared to worsen in the coming weeks.
Ebola, Lyme disease and Lassa fever are also transmitted to humans through other species, and all three could become more widespread in a warming world. But Lassa virus, a high-priority pathogen listed by the World Health Organization that could cause a public health emergency, has a entrenched presence in West Africa, and its spread is driven by climate. This is particularly worrisome because
During periods of low rainfall and an extended dry season, the common African rat Mastomys natalensis harbored the virus and had little choice but to forage in nearby human dwellings, urinating on rice, cassava, and other crops. and saliva left, stored in barrels or left alone. Hinata. When people consume these foods or have other direct exposures, it can lead to infection, usually resulting in fever and general malaise. It can also cause unpleasant symptoms, such as permanent hearing loss. The virus is estimated to infect nearly 500,000 people and claim 5,000 lives each year. In parts of Liberia and Sierra Leone, he accounts for more than 10% of hospital admissions each year.
Climate hazards may further enhance the virulence of pathogens. Heat waves can make certain viruses more resilient to heat. It causes malnutrition and stress, weakens the immune system and leaves cells vulnerable. A recent study identified 1,006 unique ways climate change could trigger the next global epidemic.
As infectious diseases emerge one after another, efforts are needed to bring them under control. The US government has invested hundreds of millions of dollars in virus surveillance programs with dramatic names such as DEEP VZN, STOP Spillover, and late HIS PREDICT. These intrepid groups of scientists put down roots deep in the crucible regions of Asia, Africa and Latin America, where human settlements, domestic animals and wildlife overlap, and zoonotic viruses are fragile. We are collecting data to model possible pathways to humans. Biomes generate new diseases.
Such interventions can predict and even speed up response to outbreaks. But no matter how sophisticated these systems are, that doesn’t stop them from having problems in the first place. While this study helps predict and theoretically contain viruses poised to invade humans, it does not address the underlying factors that prepare the microbial trampoline.
That is why we need to focus on climate change and mitigating its impacts. Reducing emissions from the biggest culprits, such as the energy, transportation and healthcare industries, can help reverse the conditions that fuel floods, heatwaves, droughts and other diseases. Minimizing our carbon footprint also reduces air pollution, reduces other environmental impacts, and improves the baseline health of our population. This will help curb the chronic diseases that leave us vulnerable during the COVID-19 pandemic, such as cardiovascular disease, diabetes and cancer, making us more vulnerable to the next threat.
But the biggest factor in preventing the pathogen leap is rethinking how we change the landscape. The biodiversity that carefully balances the numbers of rats, bats and other animals that spread infectious diseases is lost. And when urban centers stretch beyond reasonable boundaries, animal and human habitats are irrevocably bridged.
The ecological networks that connect us with our natural environment have never been clearer. It’s a relationship that we must respect. Otherwise, an unwinnable biological conflict will escalate.
Arjun VK Sharma is a writer and infectious disease specialist based in Ontario, Canada. @ArjunVKSharmaMD