World Health Organization: Climate Change is World’s Most Pressing Health Problem

Climate change is the “single biggest health threat facing humanity,” and governments must “act with urgency” to tackle the crisis, a World Health Organization (WHO) special report warns.

In advance of a United Nation’s climate change summit in early November, groups representing 45 million nurses, doctors and health professionals worldwide signed an open letter urging action on the climate crisis, CNN reported.

Both the WHO report and the open letter outline major climate issues already affecting public health. They include: air pollution from the burning of fossil fuels that causes climate change; more intense heat waves, floods and storms; extreme weather worsening food insecurity and hunger; and rising sea levels wrecking homes and livelihoods.

“As health professionals and health workers, we recognize our ethical obligation to speak out about this rapidly growing crisis that could be far more catastrophic and enduring than the COVID-19 pandemic,” the letter states. “Those people and nations who have benefited most from the activities that caused the climate crisis, especially fossil fuel extraction and use, have a great responsibility to do everything possible to help those who are now most at risk.”

“Protecting health requires action well beyond the health sector, in energy, transport, nature, food systems, finance and more,” WHO Director-General Tedros Adhanom Ghebreyesus wrote in the report’s foreword, CNN reported.

“The health arguments for rapid climate action have never been clearer,” Tedros added. “I hope this report can guide policymakers and practitioners from across sectors and across the world to implement the transformative changes needed.”

He said the report includes 10 recommendations that “provide concrete examples of interventions that, with support, can be scaled up rapidly to safeguard our health and our climate.”

They included creating climate-resilient and environmentally sustainable health systems, sustainable food production and designing sustainable cities and transportation systems, CNN reported.

“Even as they have been battling to end the COVID-19 pandemic, health leaders everywhere have been sounding the alarm on climate change,” Maria Neira, director of WHO’s Department of Environment, Climate Change and Health, said in a new release. “It is time we listened.”

Source: HealthDay

Years of Exposure to Air Pollution and Road Traffic Noise May Raise Heart Failure Risk

Exposure to air pollution and road traffic noise over the course of many years may be associated with an increased risk of developing heart failure, and the correlation appears to be even greater in people who are former smokers or have high blood pressure, according to new research published today in the Journal of the American Heart Association, an open access journal of the American Heart Association.

“We found that long-term exposure to specific air pollutants and road traffic noise increased the risk of incident heart failure, especially for former smokers or people with hypertension, so preventive and educational measures are necessary,” said Youn-Hee Lim, Ph.D., lead author of the study and assistant professor in the section of environmental health within the department of public health at the University of Copenhagen in Copenhagen, Denmark. “To minimize the impact of these exposures, broad public tactics such as emissions control measures should be implemented. Strategies like smoking cessation and blood pressure control must be encouraged to help reduce individual risk.”

This analysis examined the impact of long-term environmental exposure, specifically from air pollution and road traffic noise, on the development of heart failure in a group of female nurses in Denmark over a 15-to-20-year period.

Researchers collected data from a prospective study of over 22,000 members of the all-female Danish Nurse Cohort study. The women were 44 years of age and older at study enrollment and living in Denmark. Participants were recruited in 1993 or 1999, and when they enrolled, each woman completed a comprehensive questionnaire on body mass index, lifestyle factors (smoking, alcohol consumption, physical activity and dietary habits), pre-existing health conditions, reproductive health and working conditions. Information on heart failure diagnoses was gathered throughout the 20-year follow by linking study participants to the Danish National Patient Register, which includes records on all health care provided at hospitals in Denmark. Patient data was collected through December 31, 2014.

The study group lived in rural, urban and suburban areas throughout Denmark. To best measure individual exposure to air pollution and road traffic noise, researchers maintained records of each individual’s residential addresses, including any moves to new residences from 1970 and 2014. To determine levels of air pollution, the yearly average concentrations of two components, fine particulate matter (PM2.5) and nitrogen dioxide (NO2), were measured using a Danish air pollution modeling system. Road traffic noise levels within a three-kilometer radius from the participants’ residential addresses were estimated using a validated model system called Nord2000 and measured in decibels (dB), the standard unit for the intensity of sound.

The analysis of various pollutants and their effects on incident heart failure found:

  • For every 5.1 µg/m3 increase in fine particulate matter exposure over three years, the risk of incident heart failure increased by 17%;
  • For every 8.6 µg/m3 increase in NO2 exposure over three years, the risk of incident heart failure increased by 10%;
  • For every 9.3 dB increase in road traffic noise exposure over three years, the risk of incident heart failure increased by 12%; and,
  • Increased exposure to fine particulate matter and status as a former smoker were associated with a 72% increased risk of incident heart failure.

“We were surprised by how two environmental factors – air pollution and road traffic noise – interacted,” Lim said. “Air pollution was a stronger contributor to heart failure incidence compared to road traffic noise; however, the women exposed to both high levels of air pollution and road traffic noise showed the highest increase in heart failure risk. In addition, about 12% of the total study participants had hypertension at enrollment of the study. However, 30% of the nurses with heart failure incidence had a previous history of hypertension, and they were the most susceptible population to air pollution exposure.”

The study has several limitations. Researchers did not have information on additional variables that may have affected the results of the analysis, such as measures for each individual’s exposure to indoor air pollution or occupational noise; the amount of time spent outdoors; glass thickness of the windows of their home, which may influence noise pollution levels; if they had a hearing impairment; or individual socioeconomic status. Additionally, almost one-fourth of the original participants in the Danish Nurse Cohort were excluded from the final analysis because information was missing at the beginning of the study or at the study’s completion, so selection bias may be a contributing factor. The researchers also note that since they investigated Danish female nurses’ exposure levels and health outcomes, a generalization of the results to men or other populations warrants caution.

Previous research has shown an association between air pollution and cardiovascular disease, and the American Heart Association detailed a collection of research on the risks of pollution in a scientific statement in 2004, with additional updated findings added in 2010. In 2020 the American Heart Association American Heart Association published a scientific statement and policy guidance to address the implications of air pollution amid the COVID-19 pandemic and beyond. The policy statement discusses policy guidance at the local, state and federal levels to improve the health of our communities. Short-term exposure to high levels of some air pollutants has also been linked to heart failure.

Source: American Heart Association

The Plan to Stop Every Respiratory Virus at Once

Sarah Zhang wrote . . . . . . . . .

When London vanquished cholera in the 19th century, it took not a vaccine, or a drug, but a sewage system. The city’s drinking water was intermingling with human waste, spreading bacteria in one deadly outbreak after another. A new comprehensive network of sewers separated the two. London never experienced a major cholera outbreak after 1866. All that was needed was 318 million bricks, 23 million cubic feet of concrete, and a major reengineering of the urban landscape.

The 19th and early 20th century saw a number of ambitious public-health efforts like this. The United States eliminated yellow fever and malaria, for example, with a combination of pesticides, wide-scale landscape management, and window screens that kept mosquitoes at bay. One by one, the diseases that people accepted as inevitable facts in life—dysentery, typhoid, typhus, to name a few more—became unacceptable in the developing world. But after all this success, after all we’ve done to prevent the spread of disease through water and insects, we seem to have overlooked something. We overlooked air.

This turned out to have devastating consequences for the beginning of the coronavirus pandemic. The original dogma, you might remember, was that the novel coronavirus spread like the flu, through droplets that quickly fell out of the air. We didn’t need ventilation or masks; we needed to wash our hands and disinfect everything we touched. But a year and half of evidence has made clear that the tiny virus-laden particles indeed linger in the air of poorly ventilated areas. It explains why outdoors is safer than in, why a single infected person can super-spread to dozens of others without directly speaking to or touching them. If we are to live with this coronavirus forever—as seems very likely—some scientists are now pushing to reimagine building ventilation and clean up indoor air. We don’t drink contaminated water. Why do we tolerate breathing contaminated air?

It’s not just about COVID-19. The scientists who recognized the threat of airborne coronavirus early did so because they spent years studying evidence that—contrary to conventional wisdom—common respiratory illnesses such as the flu and colds can also spread through the air. We’ve long accepted colds and flus as inevitable facts of life, but are they? Why not redesign the airflow in our buildings to prevent them, too? What’s more, says Raymond Tellier, a microbiologist at McGill University, SARS-CoV-2 is unlikely to be the last airborne pandemic. The same measures that protect us from common viruses might also protect us from the next unknown pathogen.

To understand why pathogens can spread through the air, it helps to understand just how much of it we breathe. “About eight to 10 liters a minute,” says Catherine Noakes, who studies indoor air quality at the University of Leeds, in England. Think four or five big soda bottles per minute, multiply that by the number of people in a room, and you can see how we are constantly breathing in one another’s lung secretions.

The particles emitted when people cough, talk, or breathe come in a range of sizes. We’ve all been unwittingly sprayed by large droplets of saliva from the mouth of an overenthusiastic talker. But smaller particles called aerosols can also form when the vocal cords vibrate to air rushing out from the lungs. And the smallest aerosols come from deep inside the lungs. The process of breathing, says Lidia Morawska, an aerosol scientist at Queensland University of Technology, in Australia, is essentially a process of forcing air through the lungs’ moist passages. She compares it to spraying a nebulizer or perfume bottle, in which liquid—lung secretions, in this case—becomes suspended in exhaled air.

Even before SARS-CoV-2, studies of respiratory viruses like the flu and RSV have noted the potential for spread through fine aerosols. The tiny liquid particles seem to carry the most virus, possibly because they come from deepest in the respiratory tract. They remain suspended longest in the air because of their size. And they can travel deeper into other people’s lungs when breathed in; studies have found that a smaller amount of influenza virus is needed to infect people when inhaled as aerosols rather than sprayed up the nose as droplets. Real-world evidence stretching back decades also has suggested that influenza could spread through the air. In 1977, a single ill passenger transmitted the flu to 72 percent of the people on an Alaska Airlines flight. The plane had been grounded for three hours for repairs and the air-recirculation system had been turned off, so everyone was forced to breathe the same air.

In official public-health guidance, however, the possibility of flu-laden aerosols still barely gets a mention. The CDC and World Health Organization guidelines focus on large droplets that supposedly do not travel beyond six feet or one meter, respectively. (Never mind that scientists who actually study aerosols knew this six-foot rule violated the laws of physics.) The coronavirus should get us to take the airborne spread of flu and colds more seriously too, says Jonathan Samet, a pulmonary physician and epidemiologist at the Colorado School of Public Health. At the very least, it should spur research to establish the relative importance of different routes of transmission. “We had done such limited research before on airborne transmission of common infections,” Samet told me. This just wasn’t seen as a major problem until now.

At the University of Maryland, Donald Milton—one of the few longtime airborne-transmission researchers—is about to embark on a multiyear, controlled trial aimed at understanding influenza. Flu patients and healthy participants will share a room in this study. And they will take different precautions, such as hand-washing plus face shields or having good ventilation, which would presumably stop either droplet or aerosol transmission. The trial is meant to prove which intervention works the best, and thus which transmission route is dominant. When Milton had managed to get funding for a different aerosol study in the 2000s, he said a public-health official told him, “We’re funding you to put the nail in the coffin of the idea that aerosols are important.” Now, Milton says, “We’ll find out which direction the nail is being driven here.”

A virus that lingers in the air is an uncomfortable and inconvenient revelation. Scientists who had pushed the WHO to recognize airborne transmission of COVID-19 last year told me they were baffled by the resistance they encountered, but they could see why their ideas were unwelcome. In those early days when masks were scarce, admitting that a virus was airborne meant admitting that our antivirus measures were not very effective. “We want to feel we’re in control. If something is transmitted through your contaminated hands touching your face, you control that,” Noakes said. “But if something’s transmitted through breathing the same air, that is very, very hard for an individual to manage.”

The WHO took until July 2020 to acknowledge that the coronavirus could spread through aerosols in the air. Even now, Morawska says, many public-health guidelines are stuck in a pre-airborne world. Where she lives in Australia, people are wearing face masks to walk down the street and then taking them off as soon as they sit down at restaurants, which are operating at full capacity. It’s like some kind of medieval ritual, she says, with no regard for how the virus actually spreads. In the restaurants, “there’s no ventilation,” she adds, which she knows because she’s the type of scientist who takes an air-quality meter to the restaurant.

Earlier this year, Morawska and dozens of her colleagues in the fields of building science, public health, and medicine published an editorial in Science calling for a “paradigm shift” around indoor air. Yes, vaccines and masks work against the coronavirus, but these scientists wanted to think bigger and more ambitious—beyond what any single person can do to protect themselves. If buildings are allowing respiratory viruses to spread by air, we should be able to redesign buildings to prevent that. We just have to reimagine how air flows through all the places we work, learn, play, and breathe.

The pandemic has already prompted, in some schools and workplaces, ad hoc fixes for indoor air: portable HEPA filters, disinfecting UV lights, and even just open windows. But these quick fixes amount to a “Band-Aid” in poorly designed or functioning buildings, says William Bahnfleth, an architectural engineer at Penn State University who is also a co-author of the Science editorial. (Tellier, Noakes, and Milton are authors too; the author list is a real who’s who of the field.) Modern buildings have sophisticated ventilation systems to keep their temperatures comfortable and their smells pleasant—why not use these systems to keep indoor air free of viruses too?

Indeed, hospitals and laboratories already have HVAC systems designed to minimize the spread of pathogens. No one I spoke with thought an average school or office building has to be as tightly controlled as a biocontainment facility, but if not, then we need a new and different set of minimum standards. A rule of thumb, Noakes suggested, is at least four to six complete air changes an hour in a room, depending on its size and occupancy. But we also need more detailed studies to understand how specific ventilation levels and strategies will actually reduce disease transmission among people. This research can then guide new indoor air-quality standards from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), which are commonly the basis of local building codes. Changing the building codes, Bahnfleth said, is what will actually get buildings to change their ventilation systems.

The challenge ahead is cost. Piping more outdoor air into a building or adding air filters both require more energy and money to run the HVAC system. (Outdoor air needs to be cooled, heated, humidified, or dehumidified based on the system; adding filters is less energy intensive but it could still require more powerful fans to push the air through.) For decades, engineers have focused on making buildings more energy efficient, and it’s “hard to find a lot of professionals who are really pushing indoor air quality,” Bahnfleth said. He has been helping set COVID-19 ventilation guidelines as chair of the ASHRAE Epidemic Task Force. The pushback based on energy usage, he said, was immediate. In addition to energy costs, retrofitting existing buildings might require significant modifications. For example, if you add air filters but your fans aren’t powerful enough, you’re on the hook for replacing the fans too.

The question boils down to: How much disease are we willing to tolerate before we act? When London built its sewage system, its cholera outbreaks were killing thousands of people. What finally spurred Parliament to act was the stench coming off the River Thames during the Great Stink of 1858. At the time, Victorians believed that foul air caused disease, and this was an emergency. (They were wrong about exactly how cholera was spreading from the river—it was through contaminated water—but they had ironically stumbled upon the right solution.)

COVID-19 does not kill as high a proportion of its victims as cholera did in the 19th century. But it has claimed well over 600,000 lives in the U.S. Even a typical flu season kills 12,000 to 61,000 people every year. Are these emergencies? If so, what would it take for us, collectively, to treat them as such? The pandemic has made clear that Americans do not agree on how far they are willing to go to suppress the coronavirus. If we can’t get people to accept vaccines and wear masks in a pandemic, how do we get the money and the will to rehaul all our ventilation systems? “The costs of that kind of large-scale infrastructure remodeling are astronomical, and the tendency is to look for other kinds of fixes,” Nancy Tomes, a historian of medicine at Stony Brook University, said. It’s also a problem distributed across millions of buildings, each with its own idiosyncrasies in layout and management. Schools, for example, have struggled to get the funds and make the ventilation upgrades in time for the school year.

In their Science editorial, Morawska and her co-authors wrote, “While the scale of the changes required is enormous, this is not beyond the capabilities of our society, as has been shown in relation to food and waterborne disease, which have largely been controlled and monitored.” Morawska is optimistic, which perhaps you have to be to embark on this endeavor. The changes might take too long to matter for this current pandemic, but there are other viruses that spread through the air, and there will be more pandemics. “My whole drive is to do something for the future,” she told me.

How much actually changes “depends on the momentum created now,” she said. She pointed out that the vaccines looked like they were going to quickly end the pandemic—but then they didn’t, as the Delta variant complicated things. The longer this pandemic drags on, the steeper the cost of taking indoor air for granted.

Source: The Atlantic

Chart: Association of Global Crude Oil, Atmospheric Pollutants and Pesticide Production with Population Growth and Chronic Disease Trends

Enlarge image . . . . .

Source: Elsevier

Study: Greener Neighborhoods Bring Healthier Hearts

The greener your neighborhood, the lower your risk of heart disease.

That’s the takeaway from a new study, which reported that adding to a neighborhood’s green space can have a big payoff for public health.

“For the cost of one emergency room visit for a heart attack, trees could be planted in a neighborhood with 100 residents and potentially prevent ten heart diseases,” said study leader Dr. William Aitken, a cardiology fellow at the University of Miami.

His team analyzed data from more than 243,000 Medicare recipients who lived in the same area of Miami between 2011 and 2016.

During that time, folks in neighborhoods with high greenness were 16% less likely to develop new heart conditions than those in areas with low greenness, the study found.

Among seniors diagnosed with a new heart condition, the rate was 4% lower among those in high green neighborhoods.

Making neighborhoods more green paid off, too, the study found.

Folks whose neighborhoods where greenness increased from low to high had a 15% lower risk of new heart disease than those in neighborhoods with low greenness throughout the study.

Among participants diagnosed with a new heart condition, the rate was 9% lower for those in neighborhoods that got greener.

“Higher levels of greenness were associated with lower rates of heart conditions and stroke over time, both when an area maintained high greenness and when greenness increased,” Aitken said. “It was remarkable that these relationships appeared in just five years, a relatively short amount of time for a positive environmental impact.”

Researchers suspect several factors undergird the health benefits.

“People living in greener areas may do more outdoor exercise and might feel less stressed due to being surrounded by nature,” Aitken said. “In addition, vegetation could provide some protection from air and/or noise pollution. This is an area for further exploration.”

The findings were presented Friday at an online meeting of the European Society of Cardiology.

Research presented at meetings is typically considered preliminary until published in a peer-reviewed journal.

Source: HealthDay