Effects of Climate Change, COVID-19 Spell Concern for Embattled US Health System

The combined toll of the COVID-19 pandemic and the health effects of climate change tests an already beleaguered US health system.

In a series of events reminiscent of those seen last summer, wildfires are once again burning across the American west, bringing smoke, ash, and dust to the skies of the eastern seaboard, resulting in poor outdoor air quality conditions across the nation.

The wildfires, triggered in part by deadly heat and droughts recorded in parts of the United States and Canada, have also now been linked with increased risks of COVID-19.

Writing in the Journal of Exposure Science & Environmental Epidemiology, researchers found that in Reno, Nevada, “a 10 µg/m3 increase in the 7-day average particulate matter 2.5 (PM2.5) concentration was associated with a 6.3% relative increase in the SARS-CoV-2 [the virus which causes COVID-19] test positivity rate.”

According to authors, this finding “corresponded to an estimated 17.7% (95% CI, 14.4–20.1%) increase in the number of [COVID-19] cases during the time period most affected by wildfire smoke,” from August 16 to October 10, 2020, in the region.

This could be due to the fact that PM2.5 enhances viruses' pathogenicity through modifying immune responses and enabling the transport of the virus into the lungs, or because elevated concentrations of pollutants result in over-expression of the ACE2 receptor—the molecular target for SARS-CoV-2—in respiratory epithelial cells, which could also increase the virus' pathogenicity, researchers wrote.

The results underscore the role air pollution plays in exacerbating the COVID-19 pandemic and stress the importance of reducing exposure to poor air quality this year, as both the pandemic and wildfires continue to rage in 2021.

But one difference between the events of 2021 and those of 2020 is that this time, the extreme weather experienced by residents of North America were coupled with catastrophic flooding across parts of Europe and Asia.

In conjunction, these scenarios have experts and politicians alike decrying the effects of climate change that have started to seep into the everyday lives of residents in developed nations.

“All over the country, people are being impacted now by climate change in ways that are adversely affecting their health,” said Mona Sarfaty, MD MPH FAAFP, a family physician and director of the Medical Society Consortium on Climate and Health, in an interview with The American Journal of Managed Care® (AJMC®). Sarfaty’s group has been working for years to inform the public and policymakers about the health harms of climate change and the health benefits of climate solutions.

Despite these renewed calls made in the wake of recent catastrophes, Sarfaty stressed the importance of recognizing the “network around the [United States] of doctors and other health professionals who are trying to let their representatives know just how important it is to put in place solutions to climate change.”

In 2019, Regina LaRocque, MD, MPH, co-authored a piece in The New England Journal of Medicine deeming climate change a health emergency. “Disruption of our climate system, once a theoretical concern, is now occurring in plain view — with a growing human toll brought by powerful storms, flooding, droughts, wildfires, and rising numbers of insect borne diseases,” LaRocque wrote.

When asked to reflect on any progress made in the past 2 years, LaRocque cited increased calls from physicians and health organizations to respond to these ramifications. “On the other hand, I feel we are in a very worrisome time because I think what we have the political will to achieve is insufficient to meet the biological problems that we are facing,” she told AJMC® in an interview.

LaRocque is an infectious disease physician and scientist in the division of infectious diseases at Massachusetts General Hospital and an associate professor of medicine at Harvard Medical School. She also serves as the representative for the Infectious Disease Society of America to the Medical Society Consortium on Climate and Health and is an advisor to the Mass General Hospital Center for the Environment and Health.

“The climate crisis has worsened in the last 2 years, I think, in a way that's visible to many people now in their daily lives in a way that it has not been in the past,” LaRocque said.

But concurrent wildfires, droughts, and extreme heat do not mark the first time Americans have felt the acute ramifications of climate change.

Back in 2016, a Native American tribe in Louisiana felt some of the first impacts of climate change in North America, in that their island of residence began sinking. As a result, the Biloxi-Chitimacha-Choctaw tribe received $48 million in natural disaster grant money to resettle away from the sinking land.

“A potent combination of accelerating sea level rise, saltwater intrusion and subsidence of the land has caused devastating erosion and flooding, exacerbated further by regional oil and gas development and the shipping industry. Today, less than a quarter of the original inhabitants still live on the island, which has lost 98% of its landmass since the 1950s,” The Guardian reported at the time.

The ordeal experienced by residents of Isle de Jean Charles marks one of the first times a community in the United States undertook a complete relocation due to climate change—a pattern that has been unfolding around the globe as more populations are forced to leave their now inhabitable homelands.

As with any emergency, disproportionate ramifications are far from uncommon as vulnerable individuals tend to suffer the most from disasters.

“People who live at the margins of society are always the ones who suffer the most in an emergency situation,” LaRocque explained. “And for a long time, climate change has been relegated to being other peoples' problem, other countries' problems.”

In one study published in 2018, researchers found “an enormous global inequality where 20 of the 36 highest [greenhouse gas (GHG)] emitting countries are among the least vulnerable to negative impacts of future climate change. Conversely, 11 of the 17 countries with low or moderate GHG emissions, are acutely vulnerable to negative impacts of climate change.”

But this gap has been steadily closing over the years as more and more natural disasters occur, and first-world nations begin to suffer consequences in real time.

“It was never really the case that this was not our problem,” LaRocque said. “But now we see what's happening before our very eyes, even in our own country, and in Europe.”

Although everyone is at risk of the negative health effects of climate change, some populations, including the elderly, children, pregnant women, those with an underlying heart or lung condition, and poor populations face an increased threat for a host of reasons, Sarfaty explained.

For example, “poor people, including many people who live in communities of color who have experienced environmental injustice in the past…are also more exposed,” she said, citing the urban heat island effect.

“It turns out that there's a tremendous overlap between areas that have severe urban heat island and those areas that experienced redlining, that banks wouldn't make loans to,” in the early-to-mid 1900s, Sarfaty explained. “Those areas are concrete and asphalt and get a lot hotter in the hot weather and place people at greater risk.”

Outlining another scenario, Sarfaty stressed that when extreme weather events take place and evacuation calls are issued, populations without cars are often left with restricted options, increasing the risk of poor outcomes.

Health Impacts of a Changing Climate

According to The Lancet Countdown on Health and Climate Change’s Policy Brief for the United States of America, published in December 2020, the 6 warmest years in recorded history occurred between 2014 and 2019, while Alaska, Georgia, and North Carolina all experienced record high temperatures in 2019.

“Eight out of the 10 highest ranking years of heatwave exposure among older adults, a population especially vulnerable to heat, have occurred since 2010 in the United States,” the report reads. “In the past 2 decades, heat-related mortality for older persons has almost doubled, reaching a record high 19,000 deaths in 2018.”

All the negative health outcomes associated with increased heat, pollution exposure, and natural disasters call into question whether existing infrastructure—and particularly health care systems—will be equipped to handle the rising demand for care.

Throughout the past 18 months, American hospitals have been struggling to cope with the influx of COVID-19 patients and those suffering from conditions exacerbated by the pandemic.

In a survey conducted in February 2021—prior to the passage of the American Rescue Plan— responses from 320 hospitals across the country laid bare challenges wrought by the pandemic and the crisis’ implications in the years to come.

The report detailed officials’ fears of worsening quality of care provided to current and future patients due largely to financial struggles and staffing shortages, while administrators worried that patients who delayed care due to fears of contracting SARS-CoV-2 could result in higher hospitalization rates and increased demand for more complex care in the future.

Staff shortages resulted in administrators assigning more patients to staff, and this higher ratio can lead to mistakes as less attention is given to each patient. For example, one hospital network found an increase in central-line infections—which can be life-threatening—that they attributed to a lack of sufficient staff.

All these factors contribute to individuals deciding to retire early or seek jobs outside of the health care industry, all the while discouraging individuals from pursuing a career in the medical field. “We can’t overstate the staffing gap that exists now that’s likely to get worse over the next few years,” an administer stressed.

As the delta variant continues to spread among the nation’s unvaccinated, and states begin to report challenges of dealing with a fourth wave of cases, it seems the pandemic is far from over in the United States.

“What if we have a COVID-19 surge while we have a prolonged heatwave?” LaRocque posited, noting this combination of factors poses a double stressor on the health system. “I am very concerned that we are going to be in a consistent reactive position to a series of crises, and each time it will get harder and harder to respond.”

Some report that the influx of patients with heat-related conditions admitted to hospitals in the past months do resemble case spikes seen in the early stages of the pandemic.

“It felt very much like what happened in the initial days of trying to deal with the original outbreak [of the coronavirus],” Steve Mitchell, MD, FACEP, medical director of the emergency department at Harborview Medical Center, told The Seattle Times. “We got to the point where facilities were struggling with basic equipment, like ventilators.”

During the first heat wave in late June, Washington state reported a death toll of 78. In comparison, the state saw just 39 heat-related deaths between 2015 and 2020. In Montana, temperatures are averaging 15 to 20 degrees above normal, increasing the risk for heat-related illnesses.

With time, the situation is expected to deteriorate.

“I'm terrified by 130-degree temperatures in the west. Humans cannot live in those types of temperatures. I'm terrified by unbreathable air in my backyard,” LaRocque said. In Boston, in July “we could smell wildfire smoke from the west; the air was hazy, and the air quality index was in the dangerous level. I've lived in Boston for more than 20 years, and I've never seen anything like that. My children could smell smoke when they stepped out of the house. If that's not an emergency, I don't know what is.”

In addition to increased susceptibility to viruses resulting from air pollution, this exposure, along with stratospheric ozone depletion and rising heat, also contributes to rising rates of other conditions—one of which is skin cancer.

“Because the human population has doubled in last 50 years, the critical pressures of climate change act as force multipliers, increasingly magnifying the health impact of those pressures,” explained Eva R. Parker, MD, FAAD, an assistant professor of dermatology at Vanderbilt University Medical Center, during a panel at the American Academy of Dermatology Virtual Meeting Experience this year.

In her talk, Parker outlined how the United States already sees 5 million cases of skin cancer annually but is experiencing a steady upward trend in melanoma incidences, coinciding with increasing rates around the globe.

“As the planet continues to warm, there’s the possibility that rising temperatures could amplify the induction of skin cancer by UV radiation, further driving increased rates of skin cancer,” she said.

Not only will climate change increase rates of physical health ailments like cancer, but more natural disasters at increased frequency could result in an uptick of mental health conditions in repeatedly exposed populations.

According to The Atlantic, data show between 10% and 30% of wildfire survivors develop diagnosable mental-health conditions, including posttraumatic stress disorder (PTSD) and depression. Although another 50% may suffer from serious subclinical effects that fade with time, investigations found rates of substance abuse and domestic violence both increase after natural disasters.

LaRocque notes that just the sheer depletion of the natural world around us will also lead to adverse mental health effects.

“Loss of the natural world is a profoundly spiritually taxing experience for human beings and children in particular. It is very hard to comprehend, witnessing mass extinction,” she said.

Cognitively, increased heat will also result in negative outcomes. “Criminal activity worsens when it's hot. Children don't learn as well when it's hot. There are very profound impacts. It crosses all kinds of areas of health and humanity.”

The mental health impact of climate change is “definitely increasing,” Sarfaty noted. “Around the country, people who are displaced by storms often have long lasting anxiety, depression, PTSD. It's showing up in kids.” She continued, “Then you have young people who are just becoming increasingly distressed about what this means for the future, for their own ability to enjoy life, and have a family eventually.”

What Can Be Done?

Both LaRocque and Sarfaty agree cutting carbon emissions is paramount to reduce the impact of climate change on human health.

“There is a need for urgent decarbonization of our entire economy, which is a huge undertaking,” said LaRocque. “And that requires a focused commitment from our leaders at all levels and I'm not sure we have that yet.”

But according to Sarfaty, now is the perfect time to have this critical conversation. “Right now, as we're talking, there's the first opportunity in a decade through congressional action to address some of the underlying contributors to climate change,” Sarfaty said, alluding to the democratic congressional majority in conjunction with the Biden administration.

Although the numerous resignations of climate scientists from federal government positions may undermine efforts to meet these challenges, Sarfaty underscored the consensus among most Americans who agree on the importance of clean water and air.

“Every effort to understand public opinion shows that people are very bullish on clean air and clean water. It appeals to everyone,” she said. And as more time passes during which climate change is not addressed, the risk of poor health outcomes will only increase.

“We know what we need to do,” Sarfaty said. Cutting rates of carbon and greenhouse gas emissions by transitioning the transportation and energy sectors to clean and renewable sources is just one step that will result in less pollution and subsequent health benefits.

Currently, transportation accounts for around 28% of greenhouse gas emissions, while energy accounts for around 27%, Sarfaty explained.

For example, nitrous oxide—a greenhouse gas that has 300 times the impact of carbon dioxide when it comes to warming—is commonly emitted via transportation or agricultural processes.

When farmers use nitrogen-based fertilizers, “the nitrogen combines with the oxygen in the air, and it forms nitrous oxide….The nitrogen washes out of the ground with the increasingly heavy rains that we have—because of climate change—it washes into the waterways, and then it nurtures algae. And then that algae uses up the oxygen, leaving the water depleted of oxygen that would normally be used by the fish.” This phenomenon leads to dead zones that in turn, become uninhabitable for marine life, Sarfaty explained.

Regenerative farming is one solution to this destructive cycle, and Sarfaty stressed the valuable role renewable energy standards and carbon pricing can play in this effort.

While clean energy standards may pertain to products in the United States, working carbon pricing into the market system could help reduce the proportion of goods or services used that generated high levels of carbon in production.

As the US health care system accounts for around 10% of greenhouse gases emitted, eliminating waste in hospitals and using less energy overall could also lead to improvements.

Medical professionals see this problem and they understand the long-term impacts our current way of life will have on health outcomes, Sarfaty said.

“From a health point of view, [health impacts from climate change] is a very widespread phenomenon and there are many doctors all over the country who are seeing this in their own patients,” she said.

“They're being impacted, and they are concerned, many are alarmed. And they think that we have reached the point where we're in a public health emergency, and that we need to do something.”