It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, September 25, 2020
Modern slavery rife in NZ and Pacific Islands, charity claims
Riley Kennedy of RNZ Aug 01 2020 MARTY SHARPE/STUFF
Stephen Vaughan from Immigration NZ, left, and Detective Inspector Mike Foster speak after Matamata's sentencing.
This story was originally published on RNZ.co.nz and is republished with permission.
One in 150 people are living in "modern slavery" in New Zealand, Australia and the Pacific Islands, according to a new report by a human rights charity.
The Walk Free report identifies cases of forced labour, commercial sexual exploitation of children, and forced marriage in the Pacific.
The report, Murky waters: A qualitative assessment of modern slavery in the Pacific region, said exploitation was fuelled by widespread poverty, migration, and the abuse of cultural practices.
Senior researcher Elise Gordon said they had conducted interviews with law enforcement officers, victim support workers, policy and advocacy stakeholders, and people in the education and training industry in New Zealand, Australia, Fiji, Papua New Guinea, Samoa, the Solomon Islands, Tonga, and Vanuatu.
123RF Walk Free, a human rights charity, says New Zealand isn’t doing enough to stop modern slavery.
"We have heard reports of signs of modern slavery among migrant workers in the construction industry, stemming from increasing foreign investment in Pacific Island communities," Gordon said.
"Also fishing, a major industry in the region, brings with it a poor track record as being notorious for forced labour and human trafficking for labour exploitation."
Modern slavery was likely to increase as climate change exacerbated poverty and migration, Gordon said.
It said only a third of 54 Commonwealth countries had criminalised forced marriage and 23 nations had failed to criminalise the commercial sexual exploitation of children.
New Zealand did not do enough to stop modern slavery through its supply chain, the report stated.
Walk Free director Grace Forrest said the introduction of a modern slavery Bill should be among the New Zealand government's top priorities after the election.
The Australian government passed a Modern Slavery Act last year.
Two die in Solomon Islands bomb blast
Sep 21 2020 MORNING REPORT/RNZ Two people in Solomon Islands have died after being injured after what's thought to be a bomb from the Second World War blew up in the capital Honiara.
This story was originally published on RNZ.co.nz and is republished with permission.
Two people in the Solomon Islands have died after suffering injuries from a bomb blast in Honiara.
Police said the two, an Australian and a British citizen, were working for a Norwegian aid agency conducting a survey on unexploded ordnance.
The agency has named them as Trent Lee and Stephen Atkinson.
Inspector Clifford Tunuki said police were working overnight to clear the site of the explosion, which took place in a residential area in west Honiara. GOOGLE MAPS Police worked overnight to clear the site of the explosion, which took place in a residential area in west Honiara in the Solomon Islands.
Investigators will try to determine why explosives were present at a block of residential flats, which also serve as the project office.
The project aims to locate unexploded bombs dating back to the Second World War.
Authorities save 88 whales from Australia's worst mass beaching
Rod McGuirk, Sep 24 2020
The enduring mystery of whale beaching
As rescuers try to free a pod of around 470 stranded whales off the Australian island of Tasmania, scientists puzzle over the cause of the mysterious phenomenon.
Authorities have rescued 88 pilot whales and are attempting to free 20 others that survived Australia’s worst mass stranding, as crews prepare to remove 380 decomposing carcasses from the shallows of Tasmania state, officials said Thursday.
Crews found the 20 whales that are still alive on the fourth day of the rescue operation, Tasmania Parks and Wildlife Service Manager Nic Deka said.
“Whenever we've got live animals that have a chance and we have the resources, then we'll certainly give it a go,” Deka said.
Almost 500 whales were discovered on Monday and Wednesday beached on the shore and sand bars along the remote west coast of the island state near the town of Strahan.
As rescuers try to free a pod of around 470 stranded whales off the Australian island of Tasmania, scientists puzzle over the cause of the mysterious phenomenon.
The task of removing hundreds of tons of whale carcasses begins Friday and is likely to take days, Marine Conservation Programme wildlife biologist Kris Carlyon said.
Methods under consideration include towing the carcasses or loading them on barges to take them out to sea to be dumped somewhere where they will not drift ashore or create navigational hazards.
Carlyon said rescue crews were working 12-hour days. PATRICK GEE/AP Authorities revised up the number of pilot whales rescued from Australia's worst-ever mass stranding from 50 to 70 on Thursday.
“Everyone’s tired, feeling the fatigue, long days," Carlyon said. “The emotional toll can be significant."
Why the whales ran aground is a mystery.
Theories include that the pod followed sick whales or made a navigational error. PATRICK GEE/AP Rescue workers make a survey from a boat as they check on stranded whales near Strahan, Australia.
Tasmania is the only part of Australia prone to mass strandings, although they occasionally occur on the Australian mainland.
Australia’s largest mass stranding had previously been 320 pilot whales near the Western Australia state town of Dunsborough in 1996.
Tasmania’s previous largest stranding involved 294 whales on the northwest coast in 1935. PATRICK GEE/AP Whale carcasses are scattered along the water's edge near Strahan, Australia.
Covid-19: Leaders in Europe and Canada issue stark warnings as pandemic winter looms Emily Rauhala 12:12, Sep 25 2020
Johnson calls for 'spirit of togetherness' to survive tough coronavirus winter
Prime Minister Boris Johnson has urged the country to "summon the discipline, and the resolve, and the spirit of togetherness that will carry us through".
Brace yourselves. That's the message coming from leaders in Europe, Britain and Canada as autumn arrives, bringing with it crisp air and predictions of a dark pandemic winter. Europe faces a "decisive moment." Britain is at a "perilous turning point." Canadians probably shouldn't gather for Thanksgiving next month. KIRSTY WIGGLESWORTH/AP Leaders in Britain and Canada are issuing stark warnings as a Covid winter approaches .
Leaders are emphasising the risks ahead for countries heading into cooler months with case counts now growing again, not shrinking, and populations already fed up with pandemic restrictions.
They're highlighting the deadly seriousness of a disease that has killed nearly one million people worldwide in the first nine months of this year - and is expected to kill many more.
Experts long predicted that a summer respite from strict coronavirus measures, plus the return to schools and offices, would lead to more cases come fall. Now fall is here and cases are rising - fast.
There's little doubt they'll climb further as the weather gets colder, activities move indoors and the cold and flu season hits. Leaders see a limited window to blunt the force of the next wave.
"It is only September," said Isaac Bogoch, an infectious-disease specialist at Toronto General Hospital. "If you live in the northern hemisphere, there is a long fall and winter ahead."
There isn't much mystery as to why cases are climbing - or why it's happening now. After a brutal spring, many countries relaxed coronavirus restrictions through June, July and August, allowing citizens some simple pleasures: Visits with family, a drink at the pub, even parties for some. VICTORIA JONES/AP Leaders in Europe and Canada see a limited window to blunt the force of the next wave.
Then, through late August and September children in many countries started returning to school, allowing more parents to return to offices.
It's clear that the return to semi-normalcy has exacted a cost. The fear is that community transmission will continue, leading to a surge in hospitalisations and deaths.
Top European officials have been issuing dire warnings about the wave of new cases engulfing many countries.
"We are at a decisive moment," Stella Kyriakides, the European Union's top official for health issues, said on Thursday.
"Everyone has to act decisively," she said. "It might be our last chance to prevent a repeat of last spring."
Kluge told reporters last week that half of European countries had reported increases in cases of more than 10 per cent in the past two weeks. In seven countries, they'd doubled.
Prime Minister Jean Castex last week spoke of a "clear deterioration of the situation."
On Wednesday, the French health ministry imposed new restrictions to curb what epidemiologists are calling a "second wave" and to ease the load on hospitals. In certain urban areas, including Paris, group sizes will now be limited and bars will be required to stop serving after 10pm.
But the government has shied away from imposing another nationwide lockdown, after a strict shutdown from mid-March to mid-May.
In Britain, the mood has shifted from optimism to alarm.
Earlier this month, Prime Minister Boris Johnson said he was hopeful that some aspects of ordinary life would be "back to normal by Christmas" thanks in part to "Operation Moonshot," the government's plan to test 10 million Brits every day.
But on Monday, Patrick Vallance, the British government's chief scientific adviser, and Chris Whitty, chief medical officer for England, said cases were doubling roughly every seven days. If that rates holds, they warned, there could be 50,000 per day by mid-October.
In a televised address he explained the need: "As in Spain and France and many other countries, we have reached a perilous turning point."
Pubs and restaurants in England will now be required to close by 10pm. Masks will be mandatory for certain types of workers, including taxi drivers, retail workers and bar and restaurant staff.
"Now is the time for us all to summon the discipline and the resolve and the spirit of togetherness that will carry us through," he said.
In Canada, where the weather is already turning, the situation is also worrying.
A spike in cases in the country's four largest provinces has reversed gains made during the late spring and early summer.
Public health officials say most of the new cases are concentrated in adults aged 20 to 39, but it's only a matter of time before the virus spreads to people at greater risk.
Hospitalisations, a lagging indicator of infections, are slowly climbing. Some testing centres in Ontario have been so overwhelmed that they have reached capacity and had to turn people away before even opening.
If the country continues on its current path, public health officials say, it will reach 5000 cases a day by late October - more than at the height of its spring wave.
As in Europe, officials so far have opted for smaller and more targeted localised restrictions, keen to avoid another widespread shutdown.
Prime Minister Justin Trudeau stressed that people needed to change their behaviour to avert a winter lockdown - and save the holiday season. Thanksgiving - October 12 in Canada - is likely a wash, he said in a nationally televised address on Wednesday. But depending on how Canadians respond now, they might "have a shot" at Christmas.
"The second wave isn't just starting," he said. "It's already underway."
The Washington Post's Michael Birnbaum in Riga, Latvia, Karla Adam in London, James McAuley in Paris and Amanda Coletta in Toronto contributed to this report.
The Washington Post
China, the world's top emitter, aims to go carbon-neutral by 2060 Sep 25 2020
Net zero by 2060: China’s bold new carbon emissions goal
As US President Donald Trump dismisses climate change, Chinese President Xi Jinping says China will aim to be carbon-neutral by 2060.
Chinese President Xi Jinping says his country will aim to stop adding to the global warming problem by 2060.
Xi's announcement during a speech on Tuesday (local time) to the UN General Assembly is a significant step for the world's biggest emitter of greenhouse gases.
Calling for a “green revolution”, Xi said the coronavirus pandemic had shown the need to preserve the environment.
“Humankind can no longer afford to ignore the repeated warnings of nature,” he said.
SAM MCNEIL/AP Smoke and steam rise from a coal processing plant in Hejin in central China's Shanxi Province.
Citing the Paris Agreement that he and former US President Barack Obama helped forge in 2015, Xi said his country would raise its emissions reduction targets with “vigorous policies and measures”.
“We aim to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060,” he said.
The term “carbon neutrality” means releasing no additional CO2 into the atmosphere, though technically it allows countries to keep emitting if they ensure that an equal amount is captured again in some form.
The announcement was cheered by climate campaigners. Greenpeace executive director Jennifer Morgan called it “an important signal” that showed climate change is “top of agenda for China”.
“A big shift for curbing emissions and a significant step forward in international cooperation,” UN climate chief Patricia Espinosa said.
MARY ALTAFFER/AP Chinese President Xi Jinping remotely addresses the 75th session of the UN General Assembly.
The goal will be a challenge for China, which relies heavily for its electricity on coal, one of the most carbon-intensive fossil fuels.
China released the equivalent of 10 billion tons of carbon dioxide, or CO2, into the atmosphere in 2018, according to the Global Carbon Project that tracks emissions worldwide. That was almost twice as much as the United States and three times as much as the European Union.
Several other major emitters have set earlier deadlines, with the EU aiming to be carbon neutral by 2050. Frans Timmermans, who leads the EU executive’s efforts on climate change, welcomed Xi’s announcement.
“We need decisive action from every country to keep temperatures under control, tackle climate change and keep our planet inhabitable,” he said.
The United States has so far not set such a goal. US President Donald Trump, who once described climate change as a hoax invented by China, has started the process of pulling the US out of the Paris accord.
If China fulfils Xi’s goal, it could prevent 0.2 to 0.4 degrees Celsius further warming for the world, according to “very rough estimates” by MIT management professor John Sterman, who models and tracks emission reductions and pledges with Climate Interactive. EVAN VUCCI/AP US President Donald Trump once described climate change as a hoax invented by China.
But much depends on how they do their emissions reduction and how soon they cut them, he said, adding he has to do a more thorough analysis.
“That’s a lot,” Sterman said. “China’s by far the world’s big emitter. They're emitting more than the EU and US together.’’
“It puts a lot more pressure on the United States,” Sterman said.
Perhaps even more important than the carbon neutrality pledge is the effort to peak carbon dioxide emissions before 2030 instead of by 2030, Sterman said. Carbon dioxide’s more than 100-year lifetime in the air makes earlier emission cuts more effective than promises in the future, he said.
“Emissions that don’t happen between now and 2030 are going to reduce warming a lot more than the same emission reductions after 2060,” Sterman said.
However, pledges are not the same as actions. What’s needed is signs of action, such as eliminating plans to build new coal-fired power plants, cutting subsidies for coal power and getting off coal entirely, Sterman said. Coal is the biggest carbon dioxide emitter of power sources.
Twenty-nine nations before China have pledged to achieve climate neutrality in different years, according to the Carbon Neutrality Coalition.
With China, the 30 countries that have some kind of carbon neutrality pledges, account for about 43 per cent of the world’s carbon dioxide emissions from the burning of fossil fuels. The largest polluting countries not on the list are the United States, India, Russia, Iran, Saudi Arabia, Indonesia, South Africa, Turkey, Brazil and Australia.
AP
New research strengthens evidence for climate change increasing risk of wildfires, review finds
New scientific publications reviewed since January 2020 strengthen the evidence that climate change increases the frequency and/or severity of fire weather in many regions of the world.
Published today at ScienceBrief.org, the updated review on the link between climate change and risks of wildfires focuses on articles relevant to the fires ongoing in the western United States, new findings relevant to the southeastern Australian wildfires that raged during the 2019-2020 season, and new findings published since an initial review of research was conducted in January 2020.
The ScienceBrief Review in January looked at 57 peer-reviewed papers on the link between climate change and wildfire risk published since the IPCC's Fifth Assessment Report in 2013.
The update, led by Dr Matthew Jones of the Tyndall Centre for Climate Change Research at the University of East Anglia (UEA), covers 116 scientific articles. It involved researchers from UEA, the University of California, the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia, and Met Office Hadley Centre, at the University of Exeter.
Fire weather refers to periods with a high fire risk due to a combination of high temperatures, low humidity, low rainfall and often high winds.
The western US is among the regions where the trends in fire weather have been most pronounced in the past at least 40 years. Fire activity is influenced by a range of other factors including land management practices. However, the authors say land management alone cannot explain recent increases in wildfire extent and intensity in the western US or southeast Australia because increased fire weather from climate change amplifies fire risk where fuels remain available.
Dr Jones, a senior research associate, said: "The western US is a hot spot for increases in fire weather caused by climate change, and it is completely unsurprising that wildfires are becoming more frequent and intense in the region.
"The western US is now more exposed to fire risks than it was before humans began altering the global climate by using fossil energy on a grand scale. Regardless of the ignition source, warmer, drier forests are primed to burn more regularly than they were in the past.
"Climate models indicate that fire weather will continue to rise this century in many parts of the world, and increasingly so for each added degree of global warming. A switch to an economy supported by renewable energy sources is needed to avoid the worst impacts of climate change on fire risk."
Key messages from the new analysis:
More than 100 studies published since 2013 show strong consensus that climate change promotes the weather conditions on which wildfires depend, increasing their likelihood.
Natural variability is superimposed on the increasingly warm and dry background conditions resulting from climate change, leading to more extreme fires and more extreme fire seasons.
Land management can enhance or compound climate-driven changes in wildfire risk, either through fuel reductions or fuel accumulation as unintended by-product of fire suppression. Fire suppression efforts are made more difficult by climate change.
There is an unequivocal and pervasive role of climate change in increasing the intensity and length in which fire weather occurs; land management is likely to have contributed too, but does not alone account for recent increases in wildfire extent and severity in the western US and in southeast Australia.
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The original literature review and the update were carried out using the new ScienceBrief online platform, set up by researchers at UEA and the Tyndall Centre. Written by scientists, it helps make sense of peer-reviewed publications and keep up with science. ScienceBrief Reviews support transparent, continuous, and rapid reviews of current knowledge.
IMAGE: DATA ANALYZED FOR THE STUDY CAME FROM SOIL PROFILES, SUCH AS THIS ONE, GATHERED BY THE NATIONAL ECOLOGICAL OBSERVATORY NETWORK. view more
CREDIT: NATIONAL ECOLOGICAL OBSERVATORY NETWORK
A new way of analyzing the chemical composition of soil organic matter will help scientists predict how soils store carbon -- and how soil carbon may affect climate in the future, says a Baylor University researcher.
A study by scientists from Iowa State University and Baylor University, published in the academic journal Nature Geoscience, used an archive of data on soils from a wide range of environments across North America -- including tundra, tropical rainforests, deserts and prairies -- to find patterns to better understand the formation of soil organic matter, which is mostly composed of residues left by dead plants and microorganisms.
Researchers analyzed samples of 42 soils from archives of the National Ecological Observatory Network and samples taken from additional sites, representing all of the major soil types on the continent.
The soils were analyzed by William C. Hockaday, Ph.D., associate professor of geosciences at Baylor University, and visiting scientist Chenglong Ye, a postdoctoral scientist at Nanjing Agricultural University, in the Molecular Biogeochemistry Lab at Baylor. They used a technique called nuclear magnetic resonance spectroscopy, which allowed them to analyze the chemical structure and composition of natural organic molecules in the soil.
"Soils are a foundation of society by providing food, clean water and clean air," Hockaday said. "Soils also have a major role in climate change as one of the largest reservoirs of carbon on the planet. Even so, the chemical makeup of this carbon has been debated by scientists for over 100 years."
"With this study, we wanted to address the questions of whether organic matter is chemically similar across environments or if it varies predictably across environments," said Steven Hall, Ph.D., the study's lead author and assistant professor of ecology, evolution and organismal biology at Iowa State.
The study revealed patterns in soil organic matter chemistry that held true across climates. Understanding these patterns, or rules for how and why organic matter forms and persists in soil, will help scientists predict how soils in various ecosystems store carbon. Carbon can contribute to climate change when released from soil into the atmosphere as a greenhouse gas. An improved understanding of what kinds of soil carbon exist in different environments can paint a clearer picture of how soil carbon may affect climate and how future climate changes may affect the reservoir of soil carbon, researchers said.
"This study brought together a strong team of scientists, and for me, it was the first time to consider chemical patterns at a continental scale," Hockaday said. "It is exciting and gratifying when you inform a long-standing debate and offer an explanation of a major pattern that exists in nature."
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Tree rings show scale of Arctic pollution is worse than previously thought
IMAGE: WIDESCALE POLLUTION HAS CAUSED DEVASTATING FOREST DECLINE EAST OF NORILSK, RUSSIA. view more
CREDIT: DR ALEXANDER KIRDYANOV
The largest-ever study of tree rings from Norilsk in the Russian Arctic has shown that the direct and indirect effects of industrial pollution in the region and beyond are far worse than previously thought.
An international team of researchers, led by the University of Cambridge, has combined ring width and wood chemistry measurements from living and dead trees with soil characteristics and computer modelling to show that the damage done by decades of nickel and copper mining has not only devastated local environments, but also affected the global carbon cycle.
The extent of damage done to the boreal forest, the largest land biome on Earth, can be seen in the annual growth rings of trees near Norilsk where die off has spread up to 100 kilometres. The results are reported in the journal Ecology Letters.
Norilsk, in northern Siberia, is the world's northernmost city with more than 100,000 people, and one of the most polluted places on Earth. Since the 1930s, intensive mining of the area's massive nickel, copper and palladium deposits, combined with few environmental regulations, has led to severe pollution levels. A massive oil spill in May 2020 has added to the extreme level of environmental damage in the area.
Not only are the high level of airborne emissions from the Norilsk industrial complex responsible for the direct destruction of around 24,000 square kilometres of boreal forest since the 1960s, surviving trees across much of the high-northern latitudes are suffering as well. The high pollution levels cause declining tree growth, which in turn have an effect of the amount of carbon that can be sequestered in the boreal forest.
However, while the link between pollution and forest health is well-known, it has not been able to explain the 'divergence problem' in dendrochronology, or the study of tree rings: a decoupling of tree ring width from rising air temperatures seen since the 1970s.
Using the largest-ever dataset of tree rings from both living and dead trees to reconstruct the history and intensity of Norilsk's forest dieback, the researchers have shown how the amount of pollution spewed into the atmosphere by mines and smelters is at least partially responsible for the phenomenon of 'Arctic dimming', providing new evidence to explain the divergence problem.
"Using the information stored in thousands of tree rings, we can see the effects of Norilsk's uncontrolled environmental disaster over the past nine decades," said Professor Ulf Büntgen from Cambridge's Department of Geography, who led the research. "While the problem of sulphur emissions and forest dieback has been successfully addressed in much of Europe, for Siberia, we haven't been able to see what the impact has been, largely due to a lack of long-term monitoring data."
The expansion of annually-resolved and absolutely dated tree ring width measurements compiled by the paper's first author Alexander Kirdyanov, along with new high-resolution measurements of wood and soil chemistry, allowed the researchers to quantify the extent of Norilsk's devastating ecosystem damage, which peaked in the 1960s.
"We can see that the trees near Norilsk started to die off massively in the 1960s due to rising pollution levels," said Büntgen. "Since atmospheric pollution in the Arctic accumulates due to large-scale circulation patterns, we expanded our study far beyond the direct effects of Norilsk's industrial sector and found that trees across the high-northern latitudes are suffering as well."
The researchers used a process-based forward model of boreal tree growth, with and without surface irradiance forcing as a proxy for pollutants, to show that Arctic dimming since the 1970s has substantially reduced tree growth.
Arctic dimming is a phenomenon caused by increased particulates in the Earth's atmosphere, whether from pollution, dust or volcanic eruptions. The phenomenon partially blocks out sunlight, slowing the process of evaporation and interfering with the hydrological cycle.
Global warming should be expected to increase the rate of boreal tree growth, but the researchers found that as the pollution levels peaked, the rate of tree growth in northern Siberia slowed. They found that the pollution levels in the atmosphere diminished the trees' ability to turn sunlight into energy through photosynthesis, and so they were not able to grow as quickly or as strong as they would in areas with lower pollution levels.
"What surprised us is just how widespread the effects of industrial pollution are - the scale of the damage shows just how vulnerable and sensitive the boreal forest is," said Büntgen. "Given the ecological importance of this biome, the pollution levels across the high-northern latitudes could have an enormous impact on the entire global carbon cycle."
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Simpler models may be better for determining some climate risk
IMAGE: HOUSE IN RHODE ISLAND IN THE MIDST OF A FLOOD IN 2007. view more
CREDIT: NOAA
Typically, computer models of climate become more and more complex as researchers strive to capture more details of our Earth's system, but according to a team of Penn State researchers, to assess risks, less complex models, with their ability to better sample uncertainties, may be a better choice.
"There is a downside to the very detailed, very complex models we often strive for," said Casey Helgeson, assistant research professor, Earth and Environmental Systems Institute. "Sometimes the complexity of scientific tools constrains what we can learn through science. The choke point isn't necessarily at the knowledge going into a model, but at the processing."
Climate risks are important to planners, builders, government officials and businesses. The probability of a potential event combined with the severity of the event can determine things like whether it makes sense to build in a given location.
The researchers report online in Philosophy of Science that "there is a trade-off between a model's capacity to realistically represent the system and its capacity to tell us how confident it is in its predictions."
Complex Earth systems models need a lot of supercomputer time to run. However, when looking at risk, uncertainty is an important element and researchers can only discover uncertainty through multiple runs of a computer model. Computer time is expensive.
"We need complex models to simulate the interactions between Earth system processes," said Vivek Srikrishnan, assistant research professor, Earth and Environmental Systems Institute. "We need simple models to quantify risks."
According to Klaus Keller, professor of geosciences, multiple model runs are important because many events of concern such as floods are, fortunately, the exception, not what is expected. They happen in the tails of the distribution of possible outcomes. Learning about these tails requires many model runs.
Simple models, while not returning the detailed, complex information of the latest complex model containing all the bells and whistles, can be run many times quickly, to provide a better estimate of the probability of rare events.
"One of the things we focus on are values embedded in the models and whether the knowledge being produced by those models provides decision makers with the knowledge they need to make the decisions that matter to them," said Nancy Tuana, DuPont/Class of 1949 Professor of Philosophy and Women's, Gender, and Sexuality Studies.
Determining an appropriate model that can address the question and is still transparent is important.
"We want to obtain fundamental and useful insights," said Keller. "Using a simple model that allows us to better quantify risks can be more useful for decision-makers than using a complex model that makes it difficult to sample decision-relevant outcomes."
Srikrishnan added, "We need to make sure there is an alignment between what researchers are producing and what is required for real-world decision making."
The researchers understand that they need to make both the producers and users happy, but sometimes the questions being asked do not match the tools being used because of uncertainties and bottlenecks.
"We need to ask 'what do we need to know and how do we go about satisfying the needs of stakeholders and decision makers?'" said Tuana.
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The National Science Foundation through the Network for Sustainable Climate Risk Management supported this work.
Herd immunity an impractical strategy, study finds
Results provide insight for public health policymakers fighting COVID-19
IMAGE: PEJMAN ROHANI SOUGHT TO DETERMINE IF AND HOW COUNTRIES COULD ACHIEVE HERD IMMUNITY WITHOUT OVERBURDENING THE HEALTH CARE SYSTEM, AND TO DEFINE THE CONTROL EFFORTS THAT WOULD BE REQUIRED TO... view more
CREDIT: (PHOTO BY ANDREW DAVIS TUCKER/UGA)
Achieving herd immunity to COVID-19 is an impractical public health strategy, according to a new model developed by University of Georgia scientists. The study recently appeared in Proceedings of the National Academy of Sciences.
Controlling COVID-19 has presented public health policymakers with a conundrum:
How to prevent overwhelming their health care infrastructure, while avoiding major societal disruption? Debate has revolved around two proposed strategies. One school of thought aims for "suppression," eliminating transmission in communities through drastic social distancing measures, while another strategy is "mitigation," aiming to achieve herd immunity by permitting the infection of a sufficiently large proportion of the population while not exceeding health care capacity.
"The herd immunity concept is tantalizing because it spells the end of the threat of COVID-19," said Toby Brett, a postdoctoral associate at the Odum School of Ecology and the study's lead author. "However, because this approach aims to avoid disease elimination, it would need a constant adjustment of lockdown measures to ensure enough--but not too many--people are being infected at a particular point in time. Because of these challenges, the herd immunity strategy is actually more like attempting to walk a barely visible tightrope."
This study carried out by Brett and Pejman Rohani at the University of Georgia's Center for the Ecology of Infectious Diseases, investigates the suppression and mitigation approaches for controlling the spread of SARS-CoV-2, the virus that causes COVID-19.
While recent studies have explored the impacts of both suppression and mitigation strategies in several countries, Brett and Rohani sought to determine if and how countries could achieve herd immunity without overburdening the health care system, and to define the control efforts that would be required to do so.
They developed an age-stratified disease transmission model to simulate SARS-CoV-2 transmission in the United Kingdom, with spread controlled by the self-isolation of symptomatic individuals and various levels of social distancing.
Their simulations found that in the absence of any control measures, the U.K. would experience as many as 410,000 deaths related to COVID-19, with 350,000 of those being from individuals aged 60-plus.
They found that using the suppression strategy, far fewer fatalities were predicted: 62,000 among individuals aged 60-plus and 43,000 among individuals under 60.
If self-isolation engagement is high (defined as at least 70% reduction in transmission), suppression can be achieved in two months regardless of social distancing measures, and potentially sooner should school, work and social gathering places close.
When examining strategies that seek to build herd immunity through mitigation, their model found that if social distancing is maintained at a fixed level, hospital capacity would need to greatly increase to prevent the health care system from being overwhelmed. To instead achieve herd immunity given currently available hospital resources, the U.K. would need to adjust levels of social distancing in real time to ensure that the number of sick individuals is equal to, but not beyond, hospital capacity. If the virus spreads too quickly, hospitals will be overwhelmed, but if it spreads too slowly, the epidemic will be suppressed without achieving herd immunity.
Brett and Rohani further noted that much is unknown about the nature, duration and effectiveness of COVID-19 immunity, and that their model assumes perfect long-lasting immunity. They cautioned that if immunity is not perfect, and there is a significant chance of reinfection, achieving herd immunity through widespread exposure is very unlikely.
"We recognize there remains much for us to learn about COVID-19 transmission and immunity, but believe that such modeling can be invaluable in so-called 'situational analyses,'" said Rohani. "Models allow stakeholders to think through the consequences of alternative courses of action."
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Pejman Rohani is the Regents' and UGA Athletic Association Professor in Ecology and Infectious Diseases in the Odum School of Ecology and department of infectious diseases, College of Veterinary Medicine. Tobias Brett is a postdoctoral research associate in the Rohani lab. Research reported in this news release was supported by the National Institute of General Medical Sciences of the National Institutes of Health through a MIDAS (Models of Infectious Disease Agent Study) Program grant under award No. 5R01GM123007. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
