Climate change is, quite literally, making us ill.
The Centers for Disease Control and Prevention reported this spring that diseases from mosquito, flea and tick bites tripled in the U.S. between 2004 and 2016, with more than 640,000 cases seen during that period of time. Maine alone saw a 20-fold increase in cases of the tick-borne illness Lyme disease. The danger showed no sign of abating this year, with ticks crawling into Mainers’ lives as early as May.
Their premature arrival was largely a product of warmer temperatures in the region ― temperatures that reflect the broader trend of global climate change. It is perhaps for this reason that Lyme disease—once a regional problem largely confined to New England—has now been detected in all 50 states.
Warm weather-loving ticks and the Lyme disease they bring with them is just one example of how our rapidly-heating planet is undermining our health.
It operates much like a disease. Climate change’s “symptoms” include storms and fires, fever and smoke, and the mental and physical health challenges that characterize the long aftermath of disasters. It is through these hazards that climate change has gotten under our skin, into our lungs and weighed on our minds to the detriment of our wellbeing.
“It’s not hard to imagine how we'd respond if any other disease created all this havoc; we’d work to find the cause of the disease so we could develop a vaccine as soon as possible.”
Climate change’s most visible symptoms are the natural disasters we’ve seen so often in recent years. Shifting weather patterns caused by rising global temperatures have significantly increased the occurrence of such events, from hurricanes to floods to wildfires. According to the United Nations Refugee Agency, the worldwide number of recorded natural disasters has doubled in the last 20 years.
When a disaster strikes, the most immediate threat to health is, of course, the danger posed by the event itself. During the devastating 2017 wildfires in California and Oregon, for example, many living near the smoke reported respiratory distress and other health complications from breathing the dangerous fumes. But this initial hazard is often just a prologue to the damage these disasters can have on our health ― damage that unfolds over the course of weeks, months or even years.
Take standing flood water, for example. It’s a ripe breeding ground for mosquitoes and bacteria and can pose a serious threat in the period following a major storm. Climate change’s impact is combined with the destruction of basic infrastructure ― like power grids and drinking water delivery systems ― and the loss of core services ― like health care and waste disposal. It can both create new health challenges and complicate the treatment of existing ones.
As the threat to our physical health lingers after a disaster, so too can the threat to our mental health. As many as 30 to 60 percent of adult disaster victims experience the effects of post-traumatic stress disorder. Affected populations are also at risk of depression and the substance abuse they might initially turn to as a coping strategy. While each person’s capacity for resilience is, of course, different, the mental and physical scars of disasters have the potential to last a lifetime.
“... those who stand in the way of addressing climate change in 2018 have declared themselves friends of disease and foes of health.”
A subtler symptom of climate change is its effect on the transmission of infectious disease. In epidemiology, anything that transmits an infectious disease from one organism to another is known as a disease “vector.” A tick is an example of a disease vector. Beyond Lyme disease, climatic conditions also affect the spread of diseases like malaria, dengue fever, Zika and yellow fever by shaping the life and migration of a common disease vector: the mosquito.
A primary vector of dengue fever, for example, is the Aedes genus of mosquito. Whether or not this mosquito can live and breed in a given area largely depends on the temperature, precipitation, humidity and vapor pressure in the region. Climate change has the potential to broaden the range of where this disease can thrive ― and it appears to already be doing so. Over the last 50 years, the incidence of dengue has increased 30-fold. The disease is now poised to spread among low- and middle-income countries, where health systems are ill-equipped to shoulder this increased burden.
We’re facing a global pandemic whose symptoms include polluted air, flooded streets, burning forests, the destruction of cities and towns, injury, death, depression, PTSD, substance abuse and legions of bloodsucking, disease-carrying insects. It’s not hard to imagine how we’d respond if any other disease created all this havoc; we’d work to find the cause of the disease so we could develop a vaccine as soon as possible. But time and again, we’ve failed to take this step when it comes to climate change.
This is especially inexcusable considering we already know the main cause of the illness: global CO2 emissions. But rather than address this cause head-on, we’ve wasted valuable time while one of America’s two major political parties largely refuses to acknowledge the problem even exists, much less act to solve it by cutting back on emissions and investing in renewable energy.
“Climate change’s 'symptoms' include storms and fires, fever and smoke, and the mental and physical health challenges that characterize the long aftermath of disasters.”
Last January, for example, Paul LePage, the Republican Governor of Maine, issued an executive order placing a moratorium on the development of new wind power in the state. In taking this action just a few months before the ticks began their early approach, LePage chose to ignore the evidence before him ― and gamble with the health of his constituents. This echoed the actions of President Donald Trump, whose decision to withdraw the U.S. from the Paris climate agreement last year was, as far as health is concerned, equivalent to denying a city stricken with plague access to a supply of lifesaving cure.
The one difference is that Trump’s move has the potential to cause misery and death on a far larger scale. And this is no overstatement. Given all we know about global warming—what causes it, what we can do about it and the necessity of speed in heading off its worst effects—those who stand in the way of addressing climate change in 2018 have declared themselves friends of disease and foes of health. We cannot afford to wait for them to act any more than a doctor can afford to dally when a patient lies critically ill before her. We must collectively fight the disease of climate change ― before the symptoms worsen.
Sandro Galea is a professor and Dean of Boston University School of Public Health. His book Healthier: Fifty Thoughts on the Foundations of Population Health was published in June 2017. Follow him on Twitter at @sandrogalea.