In the midst of the global coronavirus disease 2019 (COVID-19) pandemic, countries are attempting to either recover or brace for the first wave of cases and devastating deaths. While the seasonality of COVID-19 transmissibility is largely speculation at this stage, it is suspected that the upcoming warmer months will help to attenuate the spread.[1] This will not protect us from a second wave later this year, though the belief is that it may afford us time to engage in large-scale testing, the study of antibody effectiveness, and the development of a vaccine. How climate change – a global health risk factor – is going to impact the ongoing nature of COVID-19 is not the only concern, though. Arguably the greatest concern is the lack of commensurate attention it receives in the context of global disasters, in spite of decades-old publications related to the need for preventive, integrated data and surveillance.

The concept of improved conditions during warmer months seems to be an idea that guides the lack of attention being placed on global climate change. Our immune systems are impacted by increased flux of ultraviolet radiation,[2] such that they are less capable of effectively defending against dangerous pathogens. As these pathogens are exposed to higher temperatures over time, their abilities to survive and reproduce are likely to improve within those conditions – fevers will not suffice. The same individuals who have fought against social-distancing – and continue to fight against the shutdown of the economy – are those who may be eager to enjoy warmer temperatures. These will be the cases that are asymptomatic but dangerous to others. We lack the time series data to sufficiently explain or understand what will occur in a virus that has proven to possess a transmissibility that demonstrably outweighs that of other known viruses.  

Summer months set aside, the ongoing trend of increased global temperatures has the ability to make us more susceptible to a range of viruses, even those most sensitive to climate.[2,3-5] As those with COVID-19 are recovering – assuming countries can provide equally-adequate care – they could be differentially impacted by other infectious diseases based on geography, lifestyle, and other risk factors. Recovering from acute respiratory syndromes, particularly in those who experience significant symptoms, will not benefit from increased air pollution caused by dangerous and prolonged wildfires seen across the globe.[6] This is likely the most concerning area of climate change that is underappreciated. This is not an unusual trend in many countries during times of novel and complicated situations, however. Science does not always serve as the basis for actions. This is unfortunate given how long we have been aware of concerns related to climate change and infectious diseases. Even the previously-referenced 1996 paper suggested that increased surveillance of diseases would allow for anticipatory measures,[2] yet we were globally unprepared for COVID-19.

We must not neglect the very real concern for the aggravation of another simultaneous pandemic – suicide – the peak months for deaths by suicide are generally late spring and early summer.[7] Mental health is impacted by socioecological, politico-economic, and psychological components of climate change and its ramifications. As a risk factor for suicide, those of rural communities who experience agricultural difficulties due to crop-damaging temperatures are likely to experience increased risk of financial burden.[8-9] COVID-19 is already expected to exacerbate suicidal behaviors and deaths by suicide,[7] through the very same risk factors that are equally at the mercy of climate change. Individuals experiencing anxiety disorders are at increased risk of worsening systems due to concerns related to accessing appropriate healthcare and uncertainty related to the current state of affairs.[10] This is such a concern that psychological effects are being studied at a rate greater than in the past due to perceived associations,[11] in spite of the fact that climate change is ongoing. However, climate change occurs at such a rate – and at such an unobservable fashion to those not focused on the cause – that it receives disproportionate attention while it plays a role in each of these public health concerns.

Global climate change serves as an ongoing risk factor for infectious disease, ongoing air pollution through environmental disaster, public and mental health concerns, and a host of other phenomena that negatively impact the world we know.[6,12-14] The political atmosphere in many countries undermines substantial progress in the multidisciplinary work necessary to combat these ongoing concerns. Rather than viewing the gestalt, it is not uncommon for political leaders to focus on one issue at a time, under the false premise that they are discrete events or problems unperturbed by others. Public and private companies make alterations due to external pressures to reduce their footprint, without the understanding that events are recursive and require ongoing modifications. It is not until global consensus on the deleterious effects of climate change is met that we may begin to view the catastrophic, deadly events occurring around us as mere components of a larger problem. Politics and dogma must take a backseat to the scientific processes of investigation, discovery, and implementation. 

References

 [1] Prem K, Liu Y, Russel TW, Kucharski AJ, Eggo RM, Davies N. The effect of control strategies to reduce social mixing on outcomes of the COVID-19 epidemic in Wuhan, China: A modelling study [published online March 25, 2020]. Lancet Public Health. doi:10.1016/S2468-2667(20)30073-6

[2] Patz JA, Epstein PR, Burke TA, Balbus JM. Global climate change and emerging infectious diseases. JAMA 1996;275(3):217-223. doi:10.1001/jama.1996.03530270057032

[3] Friedrich MJ. Climate change linked with increase in diarrheal disease. JAMA 2013;309(19):1985. doi:10.1001/jama.2013.5879

[4] Semenza JC, Menne B. Climate change and infectious diseases in Europe. Lancet Infectious Diseases 2009;9(6):365-375. doi:10.1016/S1473-3099(09)70104-5

[5] Altizer S, Ostfeld RS, Johnson PTJ, Kutz S, Harvell D. Climate change and infectious diseases: From evidence to a predictive framework. Science 2013;341(6145):514-519. doi:10.1126/science.1239401

[6] Vardoulakis S, Marks, G, Abramson MJ. Climate change, air pollution, and public health [published online February 28, 2020]. JAMA Intern Med. doi:10.1001/jamainternmed.2020.0703

[7] Reger MA, Stanley IH, Joiner TE. Suicide mortality and coronavirus disease 2019 – A perfect storm? [published online April 10, 2020]. JAMA Psychiatry. doi:10.1001/jamapsychiatry.2020.1060

[8] Willox AC, Harper SL, Ford JD, et al. Climate change and mental health: An exploratory case study from Rigolet, Nunatsiavut, Canada. Climatic Change 2013;121:255-270. doi:10.1007/s10584-013-0875-4

[9] Carleton TA. Crop-damaging temperatures increase suicide rates in India. PNAS 2017;114(33):8746-8751. doi:10.1073/pnas.1701354114

[10] Qiu J, Shen B, Zhao M, Wang Z, Xie B, Xu Y. A nationwide survey of psychological distress among Chinese people in the COVID-19 epidemic: Implications and policy recommendations. Gen Psychiatr 2020;33(2): e100213. doi:10.1136/gpsych-2020-100213

[11] World Health Organization. Mental health and psychosocial considerations during the COVID-19 outbreak [published March 18, 2020]. No. WHO/2019-nCoV/MentalHealth/2020.1. World Health Organization.

[12] Epstein, PR. Climate change and infectious disease: Stormy weather ahead? Epidemiology 2002;13(4):373-375.

[13] Lafferty KD. The ecology of climate change and infectious diseases. Ecology 2009;90(4):888-900. doi:10.1890/08-0079.1

[14] Greer A, Ng V, Fisman D. Climate change and infectious diseases in North America: The road ahead. CMAJ 2008;178(6):715-722. doi:10.1503/cmaj.081325