In a shack that now sits below sea level, a mother in Bangladesh struggles to grow vegetables in soil inundated by salt water. In Malawi, a toddler joins thousands of other children perishing from drought-induced malnutrition. And in China, more than one million people died from air pollution in 2012 alone.
Around the world, climate change is already having an effect on human health.
In a recent paper, Katherine Burke and Michele Barry from the Stanford Center for Innovation in Global Health, along with former Wellesley College President Diana Walsh, described climate change as “the ultimate global health crisis.” They offered recommendations to the new United States president to address the urgently arising health risks associated with climate change.
Bangladeshi children make their way through flood waters.
The authors, along with Stanford researchers Marshall Burke, Eran Bendavid and Amy Pickering who also study climate change, are concerned by how little has been done to mitigate its effects on health.
There is still time to ease — though not eliminate — the worst effects on health, but as the average global temperature continues to creep upward, time appears to be running short.
“I think we are at a critical point right now in terms of mitigating the effects of climate change on health,” said Amy Pickering, a research engineer at the Woods Institute for the Environment. “And I don’t think that’s a priority of the new administration at all.”
Health effects of climate change
Even in countries like the United States that are well-equipped to adapt to climate change, health impacts will be significant.
“Extremes of temperature have a very observable direct effect,” said Eran Bendavid, an assistant professor of medicine and Stanford Health Policy core faculty member.
“We see mortality rates increase when temperatures are very low, and especially when they are very high.”
Bendavid also has seen air pollutants cause respiratory problems in people from Beijing to Los Angeles to villages in Sub-Saharan Africa.
“Hotter temperatures make it such that particulate matter and dust and pollutants stick around longer,” he said.
In addition to respiratory issues, air pollution can have long-term cognitive effects. A study in Chile found that children who are exposed to high amounts of air pollution in utero score lower on math tests by the fourth grade.
“I think we’re only starting to understand the true costs of dirty air,” said Marshall Burke. “Even short-term exposure to low levels can have life-long effects.”
Low-income countries like Bangladesh already suffer widespread, direct health effects from rising sea levels. Salt water flooding has crept through homes and crops, threatening food sources and drinking water for millions of people.
“I think that flooding is one of the most pressing issues in low-income and densely populated countries,” said Pickering. “There’s no infrastructure there to handle it.”
Standing water left over from flooding is also a breeding ground for diseases like cholera, diarrhea and mosquito-borne illnesses, all of which are likely to become more prevalent as the planet warms.
On the flip side, many regions of Sub-Saharan Africa — where clean water is already hard to access — are likely to experience severe droughts. The United Nations warned last year that more than 36 million people across southern and eastern Africa face hunger due to drought and record-high temperatures.
Residents may have to walk farther to find water, and local sources could become contaminated more easily. Pickering fears that losing access to nearby, clean water will make maintaining proper hygiene and growing nutritious foods a challenge.
Climate change will affect health in all sectors of society.
All of these effects and more can also damage mental health, said Katherine Burke and her colleagues in their paper. The aftermath of extreme weather events and the hardships of living in long-term drought or flood can cause anxiety, depression, grief and trauma.
Climate change will affect health in every sector of society, but as Katherine Burke and her colleagues said, “….climate disruption is inflicting the greatest suffering on those least responsible for causing it, least equipped to adapt, least able to resist the powerful forces of the status quo.
“If we fail to act now,” they said, “the survival of our species may hang in the balance.”
What can the new administration do to ease health effects?
If the Paris Agreement’s emissions standards are met, scientists predict that the world’s temperature will increase about 2.7 degrees Celsius – still significant but less hazardous than the 4-degree increase projected from current emissions.
The United States plays a critical role in the Paris Agreement. Apart from the significance of cutting its own emissions, failing to live up to its end of the bargain — as the Trump administration has suggested — could have a significant impact on the morale of the other countries involved.
“The reason that Paris is going to work is because we’re in this together,” said Marshall Burke. “If you don’t meet your target, you’re going to be publicly shamed.”
The Trump administration has also discussed repealing the Clean Power Plan, Obama-era legislation to decrease the use of coal, which has been shown to contribute to respiratory disease.
“Withdrawing from either of those will likely have negative short- and long-run health impacts, both in the U.S. and abroad,” said Marshall Burke.
Scott Pruitt, who was confirmed today as the head of the Environmental Protection Agency (EPA), is expected to carry out Trump’s promise to dismantle environment regulations.
Despite the Trump administration’s apparent doubts about climate change, a few prominent Republicans do support addressing its effects.
Secretary of State Rex Tillerson, the former chairman and CEO of Exxon Mobile, supports a carbon tax, which would create a financial incentive to turn to renewable energy sources. He also has expressed support for the Paris Agreement. It is possible that as secretary of state, Tillerson could help maintain U.S. obligations from the Paris Agreement, though it is far from certain whether he would choose to do so or how Trump would react.
More promising is a recent proposal from the Climate Leadership Council. Authored by eight leading Republicans — including two former secretaries of state, two former secretaries of the treasury and Rob Walton, Walmart’s former chairman of the board — the plan seeks to reduce emissions considerably through a carbon dividends plan.
Already an issue, malnutrition will increase with droughts in Sub-Saharan Africa.
Their proposal would gradually increase taxes on carbon emissions but would return the proceeds directly to the American people. Americans would receive a regular check with their portion of the proceeds, similar to receiving a social security check. According to the authors, 70 percent of Americans would come out ahead financially, keeping the tax from being a burden on low- and middle-income Americans while still incentivizing lower emissions.
“A tax on carbon is exactly what we need to provide the right incentives and induce the sort of technological and infrastructure change needed to reduce long-term emissions,” said Marshall Burke.
Pickering added, “This policy is a ray of hope for meaningful action on climate.”
It remains to be seen whether the new administration and congress would consider such a program.
What can academics do to help?
Meanwhile, academics can promote health by researching the effects of climate change and finding ways to adapt to them.
“I think it’s fascinating that there’s just so little data right now on how climate change is going to impact health,” said Pickering.
Studying the effects of warming on the world challenges traditional methods of research.
“You can’t create any sort of experiment,” said Bendavid. “There’s only one climate and one planet.”
The scholars agree that interdisciplinary study is a critical part of adapting to climate change and that more research is needed.
“If ever there was an issue worthy of a leader’s best effort, this is the moment, this is the issue,” said Katherine Burke and her colleagues. “Time is short, but it may not be too late to make all the difference.”
Prof. Stephen Luby studied philosophy and earned a Bachelor of Arts summa cum laude from Creighton University. He then earned his medical degree from the University of Texas Southwestern Medical School at Dallas and completed his residency in internal medicine at the University of Rochester-Strong Memorial Hospital. He studied epidemiology and preventive medicine at the Centers for Disease Control and Prevention.
Prof. Luby's former positions include leading the Epidemiology Unit of the Community Health Sciences Department at the Aga Khan University in Karachi, Pakistan, for five years and working as a Medical Epidemiologist in the Foodborne and Diarrheal Diseases Branch of the U.S. Centers for Disease Control and Prevention (CDC) exploring causes and prevention of diarrheal disease in settings where diarrhea is a leading cause of childhood death. Immediately prior to joining the Stanford faculty, Prof. Luby served for eight years at the International Centre for Diarrhoeal Diseases Research, Bangladesh (icddr,b), where he directed the Centre for Communicable Diseases. He was also the Country Director for CDC in Bangladesh.
During his over 25 years of public health work in low-income countries, Prof. Luby frequently encountered political and governance difficulties undermining efforts to improve public health. His work within the Center on Democracy, Development, and the Rule of Law (CDDRL) connects him with a community of scholars who provide ideas and approaches to understand and address these critical barriers.
Director of Research, Stanford Center for Innovation in Global Health
Affiliated faculty at the Center on Democracy, Development and the Rule of Law
Objective: To study when and how an urgent public health message about a boil-water order reached an urban population after the Massachusetts water main break. Methods: In-person surveys were conducted in waiting areas of clinics and emergency departments at a large urban safety net hospital within 1 week of the event. Results: Of 533 respondents, 97% were aware of the order; 34% of those who lived in affected cities or towns were potentially exposed to contaminated water. Among those who were aware, 98% took action. Respondents first received the message through word of mouth (33%), television (25%), cellular telephone calls (20%), landline calls (10%), and other modes of communication (12%). In multivariate analyses, foreign-born respondents and those who lived outside the city of Boston had a higher risk of exposure to contaminated water. New modes (eg, cellular telephones) were used more commonly by females and younger individuals (ages 18 to 34). Individuals who did not speak English at home were more likely to receive the message through their personal networks. Conclusions: Given the increasing prevalence of cellular telephone use, public officials should encourage residents to register landline and cellular telephone for emergency alerts and must develop creative ways to reach immigrants and non-English-speaking groups quickly via personal networks. (Disaster Med Public Health Preparedness. 2011;5:235-241)
Few studies have examined the link between health system strength and important public health outcomes across nations. We examined the association between health system indicators and mortality rates.
Methods
We used mixed effects linear regression models to investigate the strength of association between outcome and explanatory variables, while accounting for geographic clustering of countries. We modelled infant mortality rate (IMR), child mortality rate (CMR), and maternal mortality rate (MMR) using 13 explanatory variables as outlined by the World Health Organization.
Results
Significant protective health system determinants related to IMR included higher physician density (adjusted rate ratio [aRR] 0.81; 95% Confidence Interval [CI] 0.71-0.91), higher sustainable access to water and sanitation (aRR 0.85; 95% CI 0.78- 0.93), and having a less corrupt government (aRR 0.57; 95% CI 0.40- 0.80). Out-of-pocket expenditures on health (aRR 1.29; 95% CI 1.03- 1.62) were a risk factor. The same four variables were significantly related to CMR after controlling for other variables. Protective determinants of MMR included access to water and sanitation (aRR 0.88; 95% CI 0.82- 0.94), having a less corrupt government (aRR 0.49; 95%; CI 0.36- 0.66), and higher total expenditures on health per capita (aRR 0.84; 95% CI 0.7 0.92). Higher fertility rates (aRR 2.85; 95% CI: 2.02- 4.00) were found to be a significant risk factor for MMR.
Conclusion
Several key measures of a health system predict mortality in infants, children, and maternal mortality rates at the national level. Improving access to water and sanitation and reducing corruption within the health sector should become priorities.
The complete article is available as a provisional PDF. The fully formatted PDF and HTML versions are in production.
BACKGROUND: Evidence suggests that gut flora may play an important role in the pathophysiology of the irritable bowel syndrome (IBS). We evaluated rifaximin, a minimally absorbed antibiotic, as treatment for IBS.
METHODS: In two identically designed, phase 3, double-blind, placebo-controlled trials (TARGET 1 and TARGET 2), patients who had IBS without constipation were randomly assigned to either rifaximin at a dose of 550 mg or placebo, three times daily for 2 weeks, and were followed for an additional 10 weeks. The primary end point, the proportion of patients who had adequate relief of global IBS symptoms, and the key secondary end point, the proportion of patients who had adequate relief of IBS-related bloating, were assessed weekly. Adequate relief was defined as self-reported relief of symptoms for at least 2 of the first 4 weeks after treatment. Other secondary end points included the percentage of patients who had a response to treatment as assessed by daily self-ratings of global IBS symptoms and individual symptoms of bloating, abdominal pain, and stool consistency during the 4 weeks after treatment and during the entire 3 months of the study.
RESULTS: Significantly more patients in the rifaximin group than in the placebo group had adequate relief of global IBS symptoms during the first 4 weeks after treatment (40.8% vs. 31.2%, P=0.01, in TARGET 1; 40.6% vs. 32.2%, P=0.03, in TARGET 2; 40.7% vs. 31.7%, P<0.001, in the two studies combined). Similarly, more patients in the rifaximin group than in the placebo group had adequate relief of bloating (39.5% vs. 28.7%, P=0.005, in TARGET 1; 41.0% vs. 31.9%, P=0.02, in TARGET 2; 40.2% vs. 30.3%, P<0.001, in the two studies combined). In addition, significantly more patients in the rifaximin group had a response to treatment as assessed by daily ratings of IBS symptoms, bloating, abdominal pain, and stool consistency. The incidence of adverse events was similar in the two groups.
CONCLUSIONS: Among patients who had IBS without constipation, treatment with rifaximin for 2 weeks provided significant relief of IBS symptoms, bloating, abdominal pain, and loose or watery stools. (Funded by Salix Pharmaceuticals; ClinicalTrials.gov numbers, NCT00731679 and NCT00724126.).
Prevention of pressure ulcers is fundamental to safe care of nursing home residents yet the role of hydration in pressure ulcer prevention has not been systematically examined. This randomized clinical trial was undertaken to determine whether administration of supplemental fluid to nursing home residents at risk for pressure ulcers would enhance collagen deposition, increase estimated total body water, augment subcutaneous tissue oxygenation, and was safe. After a baseline period, 64 subjects were randomized to receive the fluid volume prescribed or additional fluid (prescribed plus 10 mL/kg) for 5 days. Participants' potential to heal as measured with hydroxyproline was low at baseline and did not increase significantly during treatment when additional fluid was systematically provided. Fluid intake increased significantly during treatment. Estimates of total body water and subcutaneous oxygen did not increase, indicating hydration was not improved. Supplemental fluid did not result in overhydration as measured by clinical parameters. Further work is needed to examine the relationship between fluid intake and hydration in nursing home residents as well as the role of hydration in pressure ulcer prevention.
Mortality rates in the United States fell more rapidly during the late nineteenth and early twentieth centuries than in any other period in American history. This decline coincided with an epidemiological transition and the disappearance of a mortality "penalty" associated with living in urban areas. There is little empirical evidence and much unresolved debate about what caused these improvements, however. In this article, we report the causal influence of clean water technologies -- filtration and chlorination -- on mortality in major cities during the early twentieth century. Plausibly exogenous variation in the timing and location of technology adoption was used to identify these effects, and the validity of this identifying assumption is examined in detail. We found that clean water was responsible for nearly half the total mortality reduction in major cities, three quarters of the infant mortality reduction, and nearly two thirds of the child mortality reduction. Rough calculations suggest that the social rate of return to these technologies was greater than 23 to 1, with a cost per person-year saved by clean water of about $500 in 2003 dollars. Implications for developing countries are briefly considered.
Health Economist Mark Smith is a Vice President at CATHEXIS and a Stanford Health Policy Adjunct Affiliate. From 2001-2011 he was an economist at VA Palo Alto. At Truven Health Analytics (2012-2016) and IBM Watson Health (2016-2020) he led projects in quality measurement and reporting and provided technical assistance to state Medicaid agencies.
His research focuses primarily on quality measurement, mental health and substance abuse, and economic analyses. He led a team that collaborated with Stanford Health Policy and others to develop health care quality indicators based on emergency department services. International projects have included implementation of health care quality measurement in the Emirate of Abu Dhabi and determining predictors of sustainability in water-quality improvement projects in Nicaragua. He earned a B.A. at Oberlin College and M.A., M.Phil., and Ph.D. degrees at Yale University, all in economics.
Adjunct Affiliate at the Center for Health Policy and the Department of Health Policy