Dramatic loss of food plants for insects

by University of Bonn

Credit: © Armin Heitzer

Just a few weeks ago, there were news headlines about plummeting insect numbers. Academic discourse focused on three main causes: the destruction of habitats, pesticides in agriculture and the decline of food plants for insects. A team of researchers from the Universities of Bonn and Zurich and the Swiss Federal Institute for Forest, Snow and Landscape Research WSL have now demonstrated for the first time that the diversity of food plants for insects in the canton of Zurich has dramatically decreased over the past 100 years or so. This means that bees, flies and butterflies are increasingly deprived of their food base. The study, which is representative for all of Central Europe, has now been published in the journal Ecological Applications.

"Over the past 100 years, there has been a general decline in food plants for all kinds of insects in the canton of Zurich," says Dr. Stefan Abrahamczyk from the Nees Institute for Biodiversity of Plants at the University of Bonn. The homogenization of the originally diverse landscape has resulted in the disappearance of many habitats, especially the wetlands, which have shrunk by around 90 percent. Human settlements have spread more and more at the expense of cultivated land, and the general intensification of pasture and arable farming has led to a widespread depletion of meadows and arable habitats. The researchers compared the abundance of food plants of different insect groups, based on current mapping for the years 2012 to 2017, with data-based estimates from the years 1900 to 1930 in the canton of Zurich (Switzerland).

The food plants of specialized groups of flower visitors are particularly affected by the decline. For instance, the Greater Knapweed (Centaurea scabiosa) is pollinated by bumblebees, bees and butterflies, as their tongues are long enough to reach the nectar. The decline is particularly dramatic for plant species that can only be pollinated by a single group of insects. In the case of Aconite (Aconitum napellus), for example, this can only be done by bumblebees because the plant's toxin evidently does not affect them.

Overall, all plant communities have become much more monotonous, with just a few dominant common species. "It's hard for us to imagine what vegetation looked like 100 years ago," says Dr. Michael Kessler from the Department of Systematic and Evolutionary Botany at the University of Zurich. "But our data show that about half of all species have experienced significant decline in their abundance, while only ten percent of the species have increased."

Credit: © Beat Wermelinger

250 volunteers helped with mapping

Residents with appropriate botanical knowledge helped with the current survey. They mapped the entire canton of Zurich by plotting an area of one square kilometer each at intervals of three kilometers. The focus here was on the different types of vegetation and the abundance of different plants. "Without the assistance of more than 250 volunteers, who not only mapped the current flora but also processed the historical collections, a project of this scope would not have been feasible," says Dr. Thomas Wohlgemuth of the Swiss Federal Institute for Forest, Snow and Landscape Research WSL, who initiated the mapping project ten years ago with the Zurich Botanical Society.

The most important source on the earlier flora in the canton of Zurich was the unpublished manuscript of Eugen Baumann, a collection of about 1200 handwritten pages. It contains precise and detailed information on the abundance and distribution of plant species before 1930. Dr. Abrahamczyk researched which of the listed species belong to those flowering plants that are visited by insects in search of pollen and nectar. The "customers" include bees, bumblebees, wasps, butterflies, hoverflies, flies and beetles.

Results are largely transferable to Central Europe

Dr. Abrahamczyk has been working on pollination biology for about ten years. He wrote his doctoral thesis at the University of Zurich, then conducted research at the LMU Munich and joined the Nees Institute of the University of Bonn in 2014. When, in late 2018, his former doctoral supervisor, Dr. Michael Kessler, suggested that the recently completed mapping of the canton's flora be combined with pollinator data, Dr. Abrahamczyk was immediately enthusiastic—also because this subject is highly topical. "The laborious literature search and analysis then took some time, and now the study could finally be published," says the scientist from the University of Bonn. "The results are transferable to the whole of Central Europe with minor regional restrictions."

Flies and bees act like plant cultivators

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More information: Stefan Abrahamczyk et al, Shifts in food plant abundance for flower‐visiting insects between 1900 and 2017 in the canton of Zurich, Switzerland, Ecological Applications (2020). DOI: 10.1002/EAP.2138

Journal information: Ecological Applications 

INDOOR AIR/ENVIRONMENTAL QUALITY

A five-layered approach to safely reopening workplaces

by Alvin Powell, Harvard University

Credit: Kate Sade/Unsplash

A Harvard healthy-buildings expert has laid out a lower-cost, five-layered approach for employers and building managers as they consider how to safely reopen their establishments and get America back to work.

Joseph Allen, assistant professor of exposure, assessment science at Harvard T.H. Chan School of Public Health and director of the School's Healthy Buildings Program, said existing safety guidelines called the "hierarchy of controls," normally used to reduce risk in situations such as hazardous chemicals in the workplace, would be suitable for blocking exposure to COVID-19.

The system used by the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH) consists of five steps, with the use of personal protective equipment being the last, Allen said. They include:

• Hazard elimination, which means keeping employees home, a tactic that works for some, but not others, and won't lead to full economic recovery.
• Personnel substitution, in this case initially bringing back just those key employees who need to be physically present to get and keep the business running.
• Engineering controls, including healthy-building strategies such as increasing the flow of outside air, using portable air purifiers, and swapping existing filters in air circulating systems for ones that can capture smaller particles.
• Administrative controls, such as de-densify buildings by having portions of the workforce come in on alternate days or staggering shifts within a day. This might also include spreading workers out in space and limiting the use of conference rooms for large gatherings.
• Use of personal protective equipment (PPE), such as the now-familiar cloth face coverings, respirators, and other gear in common areas and situations where other controls don't achieve the required level of safety.

"I haven't yet come across an environment where putting in sensible controls isn't able to significantly reduce the risk," said Allen, who is deputy director of the NIOSH Education and Research Center on Worker Health and Safety.

There are additional actions that could be tailored to each workplace, Allen said. Employers could rearrange desks so workers would be offset instead of sitting directly across from each other; ensure hard surfaces are regularly disinfected; or position portable air purifiers near employees. Things like managing lines near elevators and ensuring PPE is used inside them would also be important.

Allen, who spoke to the media on a conference call Thursday, said the guidelines constitute a relatively low-cost roadmap for employers thinking about bringing people back to work. He cautioned against assuming any one action will provide complete protection, but said it's rather a matter of understanding and managing risks, not just putting a mask on everyone who walks through the door.

"There is no silver bullet here," Allen said. "You don't give someone a mask and say, "Our responsibilities are done.'"

Credit: Josh Lasky

Allen also cautioned that managing risks doesn't mean there will be no transmission.

"Everyone has to be really clear. There's no such thing as zero risk," Allen said.

And these guidelines don't mean businesses should reopen before it's safe to do so. Several Chan School epidemiologists and infectious disease experts have urged current social-distancing restrictions remain in place until case numbers have declined, health care system capacity is sufficient to handle a new increase in cases, and adequate testing is in place to detect any new surge in cases.

"I'm not talking about 'when,'" Allen said. "I'm talking about when they say it's clear, how you go about this safely."

There's a common misperception that strategies will necessarily be expensive, he said, but simple things like installing more efficient filters, increasing the supply of fresh air, and enhancing disinfection are well within the reach of most business owners.

"There are technology solutions that are being considered that are more expensive, require a big capital outlay, might take a couple of months to implement. But … I'm being cognizant we have to put in right now strategies that people can take and deploy in almost any situation," Allen said. "Broadly, these are strategies that people can put in and the costs are low or manageable."

Steps taken in the workplace, however, don't get everyone safely through their commutes. Those who drive or walk may have fewer concerns, but those who take public transportation face a tougher challenge, Allen said. For those taking car transport—taxis, Ubers, Lyfts—models have shown that simply opening a window three inches significantly decreases concentrations of airborne contaminants inside. For those whose commutes include time on subway trains and buses, however, he said more work still needs to be done.

"It's a vexing problem, everything about this pandemic is," Allen said. "I'm confident that we'll get there."

How buildings, masks can be barriers to coronavirus

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Provided by Harvard University 

Most firms neglected to include pandemic in annual risk assessments despite warning signs, study shows

by University of Notre Dame

Credit: CC0 Public Domain

Public companies in the United States are required to file annual reports that, among other things, disclose the risk factors that might negatively affect the price of their stock.

The risk of a pandemic was known prior to the current health crisis, yet managers, in disclosing their companies' risk factors to shareholders in 2018, showed little foresight in terms of the impact and likelihood of a pandemic, according to new research from the University of Notre Dame.

In "Management Disclosure of Risk Factors and COVID-19," Bill McDonald and Timothy Loughran, finance professors at Notre Dame's Mendoza College of Business, examine all 10-K filings (annual reports filed with the Securities and Exchange Commission) from 2018, before the current pandemic, and find that less than 21 percent of the filings contain any pandemic-related terms.

"Pandemic risk was well known before today's crisis and we now know the impact for shareholders is significant and negative for the majority of companies," McDonald said. "Given management's presumably deep understanding of their businesses and general awareness that, for at least the past decade, pandemics have been identified as a significant global risk, the percentage of firms listing it among other low-probability events, like earthquakes, asteroids and volcanoes, should have been higher."

McDonald and Loughran applied their ongoing research, which utilizes textual analysis to gauge the tone of financial documents, to the coronavirus pandemic. And while they found many firms listed other low-probability events among potential risks, McDonald says legitimate warnings about pandemics dominated any real concerns about other types.

"Of course, hindsight makes things obvious," McDonald said, "but I think the risk of a pandemic was significant and, more importantly, it has the potential to cause more damage to most firms. A small portion of those firms, including Disney and Carnival Cruise Lines, acknowledged the risk."

Stock values have taken an enormous hit as a result of the pandemic, and McDonald says managers should have known better.

"Health organizations and reputable news sources had been emphasizing that a pandemic was a likely event," he said. "Informing shareholders of all potential risks associated with investing in a company is a critical part of the disclosure process. Perhaps companies need to go beyond standard templates in identifying unusual but relevant events that could impact the value of their firm."

Guidance issued for breast cancer care during COVID-19

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More information: Tim Loughran et al. Management Disclosure of Risk Factors and COVID-19, SSRN Electronic Journal (2020). DOI: 10.2139/ssrn.3575157

Provided by University of Notre Dame 

Video: How does alcohol kill coronavirus?

by Pennsylvania State University

Credit: CC0 Public Domain

How does alcohol kill this virus? With the onset of the COVID-19 pandemic, alcohol-based hand sanitizer became a much-sought item by hospitals and the general public alike for its ability to inactivate the coronavirus.

CIDD's Dr. Nita Bharti explains how the alcohol does this, and which concentrations are effective.

Credit: Pennsylvania State University

Hand sanitizer has an expiration date. Does it matter amid coronavirus outbreak?

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Provided by Pennsylvania State University

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Contagion, xenophobia and leadership can trigger a misguided search for a scapegoat

by Martin J. Smith, Stanford University

Credit: Oula Lehtinen/Wikipedia

The ongoing COVID-19 outbreak has been a sort of Rorschach test. In addition to revealing deep strengths and ingenuity in the American community, it also has exposed some of America's deepest fears, xenophobic tendencies, and dysfunctions of leadership.

Those are among the conclusions of Hayagreeva "Huggy" Rao, the Atholl McBean Professor of Organizational Behavior and Human Resources at Stanford Graduate School of Business. Rao coauthored two studies in recent years that form the basis of his strong conclusions.

In one study, published in 2018, he studied the predictable rise of contamination rumors and ethnic violence that often follow an outbreak of an infectious disease. Rao says he and coauthor Sunasir Dutta of the University of Minnesota found that "exposure to discourse about contagious disease activates xenophobic tendencies in people. When you're exposed to this discourse, you're much more likely to believe rumors."

Rao's more recent study, done with colleagues Chelsea Galoni of the University of Iowa and Gregory Carpenter of Northwestern, looked at the underlying emotions triggered by contagious diseases.

"The conventional wisdom is that, if there is contamination, our response is one of disgust," Rao says. "But Chelsea, Greg, and I felt this was a somewhat incomplete account."

They concluded that perceived contamination actually triggers two emotions: disgust and fear. "There's a big difference between fear and disgust," he says. "With disgust, you know the cause is certain and that's why you shrink away. But with fear, the outcome is uncertain. That's why you're afraid. You don't quite know what's going to happen."

What does all of this show? "It lends credence to the idea that when you have a contagious disease, you become xenophobic and you perceive everyone else as a threat."

Is COVID-19 exacerbating cultural biases in ways you didn't expect, or is it playing out as your studies predicted?

If we know contagious disease can lead to xenophobia and loss of trust in strangers, what we need most is leadership. It's essential.

What kind of leadership?

First, we expect them to anticipate the unexpected. That doesn't mean they need to divine all of this by themselves, but we presume they have good people working for them and they listen to those people. However, leaders systematically underestimate the coordination difficulties going in. Some studies show that if you're in a leadership position, you're likely to underestimate coordination difficulties by at least 50%.

Second?

Leaders need to bear in mind that citizens are in a room called Fear, and they want to be taken to a room called Safe. Creating psychological safety is very important for leaders when you have contagious diseases. People expect to be assured that the community is committed to solving the problem. Even though the government may not be able to assure their continued existence, people need to be assured that everyone is doing their best.

So how is the U.S. leadership doing in that regard?

It's difficult for people to feel a sense of safety when they get conflicting messages, and when they see leaders display a blaming or scapegoating mentality. It's sort of weird that in the American narrative, exigencies, emergencies, and crises are frequently likened to war. Everything is a war. The war on drugs. The war on COVID. I'm a "wartime leader." Whatever. But if you really look at wartime leaders, they behave in a striking manner.

Striking in what way?

I think the best military leader America ever had was Matthew Ridgway. Ridgway was a brigadier general during World War II. He replaced Douglas MacArthur on the Korean operation. He'd never fought in Asia, never led a land battle. He had no idea about Korea. As soon as he took charge, he spent the first couple of days flying around Korea. He took the navigator's seat. They flew all over, noting rivers, lakes, mountains. Once he understood the geography and topography of Korea, he met regimental commanders and would ask them a series of questions to assess their leadership readiness. Often, his first questions had to do with geography. Where's the nearest river? How deep is it? If the commander wasn't able to answer, he was fired instantly because he was going to endanger their troops. That is wartime leadership.

Do you feel public officials typically help or hinder in terms of community cooperation?

Most of them want to do the right thing, including mayors and other community leaders. This morning I was reading about the school superintendent in the poorest county in Mississippi who is using his buses to deliver food to children who otherwise might starve. And he's doing it at some risk to himself. I find that extraordinary. That's leadership.

One key takeaway from one of your earlier studies was that the fear of contagion makes people irrational, as happened in the AIDS epidemic in San Francisco in the 1980s, when conservative groups focused on the morality of homosexuality rather than on managing the risks to public health. What's the most effective way to combat that sort of irrationality during a public health crisis?

The place to begin is to understand we're involved in a team sport. What's our job now? To help all of the people in the hospitals. How? By staying at home so we don't infect more people. In a team sport, everybody needs to commit.

What is it about the fear of contagion that makes otherwise rational people buy into unfounded rumors about those they consider to be outsiders?

One thing is that your own mortality becomes very salient. And then you add to that a fear of the unknown. You know you could die, but with no idea when or how. So there's all this uncertainty, and uncertainty is paralyzing. A good way to tame your fear—especially if leaders make it available—is to blame some other group for the origin of this. You have the Black Plague in the Middle Ages, and who got blamed? Jews got blamed. Take different contagious disease outbreaks, and usually a different group gets blamed every time. You can see this now in America.

How so?

We've had incidents of Chinese-Americans, Japanese-Americans, Korean-Americans who've been threatened, castigated, or criticized because the virus came out of Asia. That's the danger always with these contagious diseases. To put it simply, when we look at disasters, we often think the disaster is the problem. But what we need to understand is that disasters become catastrophes only when a society's cultural protections wither away or collapse. Our norms of civility, our norms of solidarity, begin to crumble when fear is coupled with disgust.

Is what's happening now just a continuation of the kind of xenophobia we've seen during past pandemics? Or is this something altogether different?

Xenophobia tendencies are always latent. They need opportunities to bubble up. You can think of COVID as one ramp by which this bubbling up happens. There are many, but that's one of them. It's not that COVID creates something out of nothing. The virus accentuates what's already there, lurking in the background, dormant. What COVID does is intensify it.

You sound pretty discouraged by what you've seen so far. But are there signs that give you hope?

I love what our students are doing, despite the fact that they're all afraid and thinking, "Am I gonna get a job? Am I gonna get an internship?" They're doing amazing things on campus, all on their own initiative. That gives me confidence. There are always tributaries of goodwill, solidarity, bringing out the best in people. My sincere hope is that this has been an education to the American people as to what government can and should do, and what venality can and cannot do.

In 2018 you concluded that a community's resilience hinges on two critical factors: How the disaster is framed by the community and its leaders, and how cooperative the community is in dealing with challenges. How prepared do you think the U.S. was for the coronavirus outbreak in terms of community cooperation?

We often think of preparedness as capability, but if you ask psychologists, they tell you preparedness is also motivation. It's a state of adaptive readiness. The short answer is that parts of the government, universities, public health people, and schools of medicine were certainly aware, and they were all highly concerned. The U.S. has some of the best contagious disease experts in the world. They're like Navy SEALs who specialize in vector-borne diseases. And yet we were not able to take advantage of their help. There was no understanding of all of this so it could translate into some sort of legislative strategy or set of executive priorities. It's been a confederacy-of-dunces kind of planning.

You've described charities and nonprofit organizations as critical factors in a society's resilience during a crisis such as this, because they help absorb the shock.

They are vital shock absorbers in any community. Take them away and you'll be in trouble. To my mind, this is another omission. I see all these budgets and outlays for businesses, and of course that's a useful thing to have, but what about nonprofits? Who's going to help them? They're the ones running the soup kitchens and doing the feeding and distribution. Without those shock absorbers, it's going to be very tragic.

You cite the work of public policy professor Robert Putnam of Harvard University, who compares social cooperation to the lubricant WD-40, which reduces friction. How do you rate our social cooperation during the coronavirus pandemic?

We need a lot more WD-40, sadly. In the end, be compassionate, be kind, and be generous. Period.

How different societies react to pandemics

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More information: Chelsea Galoni, et al. (2017), Pathogen Fear and the Familiar, in NA - Advances in Consumer Research Volume 45, https://www.acrwebsite.org/volumes/1023625

Coronavirus calm reveals flourishing Venice Lagoon ecosystem

by Giovanna Girardi

Coronavirus has emptied Venice of millions of tourists and its waters are no longer stirred by the thousands of boats, usually cross it

"The flora and fauna of the lagoon have not changed during lockdown. What has changed is our chance to see them," says zoologist Andrea Mangoni, plunging his camera into Venice's normally murky waters to observe life.

A crab tries to grab the intruding lens, jellyfish propel themselves along near the surface, schools of fish swim peacefully by, crustaceans cling to the city's famous jetties, and seaweed of every colour wafts gently on the current.

The coronavirus has emptied Venice of millions of tourists since the beginning of March and its waters are no longer stirred by the thousands of boats, taxis, vaporetti, and gondolas that usually cross it.

For Mangoni, this is an opportunity to rediscover the very diverse ecosystem that populates the Venice Lagoon. His film of a jellyfish swimming slowly though translucent canal water has gone viral on social media.

"Now we can see 50 or 60 centimetres, and sometimes even a metre from the surface. As a result, we can see animals that were literally hidden in the murky waters."

Mangoni says he has never seen such clear waters in the 20 years he has worked in Venice.

"The only difference is that some animals that before were relegated to bigger or wider canals in the lagoon, can now go as far as in the city centre since the traffic of gondolas, motorboats and smaller boats has ceased," he said.

Urban jelly fish

Marco Sigovini, researcher at the Institute of Marine Sciences of Venice (ISMAR-CNR), says he has seen marine species in the centre of the former city state for the first time.

With the boat traffic halted, marine species are being seen in the centre of the former city state for the first time

"Fauna and flora of Venice Lagoon are much more diversified and interesting than what one might think," he said.

"What decreased in the city is not only traffic with pollution produced by boats, but also the noise, which is another kind of pollution and disturbs many lagoon organisms."

Nevertheless, he is not surprised at how many jellyfish are being observed.

"Over the last 20-30 years jellyfish have increased in numbers generally. They come into the lagoon more and more frequently, particularly at certain times of year, perhaps carried by the current," he said.

"Normally, there's a lot of traffic so it's likely many of them are often killed."

Mangoni takes pictures and videos on his way to work and says life in Venice these days is "like being on a coral reef".

"The number of colours and lifeforms is extraordinary, which makes the lagoon unique," he said.

But Sigovini does not think much will change long-term for Venetian fauna.

"Most likely these few months of lockdown won't suffice to really change the quality of our ecosystem," he said.

Image: Deserted Venetian lagoon

Poor Amazonians go hungry despite living in one of the most biodiverse places on Earth

by Lancaster University

A fish's eye view of today's catch from inside the canoe on a lake beside the River Purus during the low water season. Credit: Daniel Tregidgo

Poorer rural Amazonians are going hungry despite living in one of the most biodiverse areas on the planet—a new study reveals.


Massive seasonal floods mean many ribeirinhos, a marginalised social group who live alongside rivers in Brazil's Amazonian floodplain forests, struggle to catch enough fish to eat and can go hungry.

The Purus River, which flows towards the regional capital city of Manaus, undergoes one of the largest annual variations in water levels on the planet. When it floods, large areas of forest become submerged. River fish populations disperse making them much harder to catch.

The difficulty in catching fish during the floods might partially explain widespread malnutrition among vulnerable Amazonians, having serious lifelong health consequences, especially when affecting pregnant women and young children.

Policy makers and scientists had assumed that tropical areas containing very large forests contain enough food for the relatively sparse rural population.

Today, a team of scientists from Brazil and the UK are publishing the results of the first study linking food security for wildlife-dependent people in the Amazon with 'catch rates' - which is the amount of fish caught for each hour spent fishing.

Largely invisible to many policy makers and wider Brazilian society, the ribeirinhos, are some of the poorest people in Brazil, living in small communities dispersed over thousands of kilometres along Amazonian river systems. They often live far away from shops and lack electricity, refrigeration, or the ability to keep livestock. Therefore, ribeirinhos obtain a large proportion of their calories, macronutrients and micronutrients from catching fish.

Fishing for the world's largest freshwater scaled fish, pirarucu (Arapaima gigas), in a lake beside the River Purus. Credit: Daniel Tregidgo

During seasonal floods local people must spend around three times as long fishing compared to low water levels, using different techniques including more hooks, and fishing in different habitats—such as shallow flooded forests.

Despite their increased efforts fish catches fall by around half with catch rates reduced by 73 per cent.

This reduced food security during floods means families are forced to go without food for whole days, skip meals, or eat smaller portions.


Daniel Tregidgo, of the Federal University of Lavras in Brazil and Lancaster University in the UK is lead author on the study. He said: "The study highlights how the food security of marginalised rural communities living in a biologically rich area relies heavily on the stable supply of wildlife. Seasonal floods bring severe food insecurity among wildlife-reliant people by disrupting that supply despite being in an area of great natural wealth.

"This high prevalence of food insecurity seems paradoxical for Amazonian várzea forests which are biologically rich and have low human population densities but the population is highly dependent on this seasonally-transformed ecosystem.

"This study's findings indicates that we may be overlooking food instability in areas around the world where people are reliant on wildlife for food. This instability is potentially very common and dangerous for human health."

Researchers found that ribeirinhos also try to make up for their reduced fish catches by spending more time and effort hunting for bushmeat in the forests.

River Purus fisherman preparing the day's catch of tambaqui (Colossoma macropomum) and pirapitinga (Piaractus brachypomus) outside his house. Credit: Daniel Tregidgo

Paulo Pompeu from the Federal University of Lavras explains the potential implications of these findings across the Amazon: "Because the Amazon basin is experiencing a boom in construction of hydropower dams, such a major threat to fish stocks could lead to an increase in hunting pressure on land animals."

The findings that ribeirinhos both fish and hunt more when food security is reduced shows just how much they rely on wildlife.

The authors say that this evidence shows how effective management of river and forest wildlife populations is vital to ensure that remote rural communities can feed themselves in the high water season. Management of commercial fishing is particularly important, and the authors' previous research showed that fish stocks in the forest can be depleted by meeting the demand from large Amazonian cities, up to 1,000km away.

The study also found food insecurity hits the poorest hardest. Only the least-poor minority of ribeirinhos are able to protect themselves from seasonal food scarcity.

Researchers say the results show that the solution to food insecurity in the high water season is poverty alleviation for rural households. This raises important policy debates, particularly around welfare and fishing closed-season payments. They say that reliable provision of school meals in rural areas will also help support the diets of children in vulnerable households during times of low fish catches.

The researchers interviewed residents from 22 rural communities at least 13km apart from each other covering a distance along the river of 1,267km.

The findings are presented in the paper 'Tough fishing and severe seasonal food insecurity in Amazonian flooded forests' which has been published in the journal People and Nature.
Rainforest metropolis casts 1,000 km shadow on wildlife

More information: Daniel Tregidgo et al, Tough fishing and severe seasonal food insecurity in Amazonian flooded forests, People and Nature (2020). DOI: 10.1002/pan3.10086

IT'S SCIENCE  FRICTION MONDAY

Massive U.S. contact tracing effort 'of critical importance'

by Katie Pearce, Johns Hopkins University

Credit: CC0 Public Domain

Before the United States can reopen safely, a new workforce at least 100,000 strong should be in place to trace the contacts of people diagnosed with COVID-19, according to a report from the Johns Hopkins Center for Health Security and other experts.

A long-used public health tool, contact tracing aims to break the chain of transmission of a contagious disease by identifying and alerting those who may have been exposed to it. Traditionally, a trained contact tracer will interview an individual diagnosed with the disease to determine all of their recent contacts, then reach out to those contacts to provide further information—which may include a recommendation to self-quarantine. In the past, this meticulous strategy has been used to help control Ebola, SARS, sexually transmitted infections, and tuberculosis, among other communicable diseases.

With the global outbreak of COVID-19, public health experts believe contact tracing will be a critical step for containing the virus, alongside social distancing and widespread testing. Many countries have already deployed extensive contact tracing, including New Zealand, Iceland, Taiwan, Singapore, and South Korea.

The United States, too, is gradually ramping up efforts—including a new hiring surge funded by the CDC, a Google/Apple tech partnership, and a statewide program in Massachusetts. In New York, Gov. Andrew Cuomo is working with Bloomberg Philanthropies to launch a massive contact tracing program that will include online training from the Johns Hopkins Bloomberg School of Public Health.

"In the absence of a vaccine, we think this is really the big public health tool we have to control transmission of COVID-19," says Crystal Watson, a lead author of the new report and assistant professor in the Bloomberg School. "We need to push hard for this."

The report acknowledges that a contact tracing effort of this magnitude—"and of this critical and historical importance for the functioning and reopening of society"—is without precedent. In an interview with the Hub, Watson offered more insight on the significance of this approach and the challenges ahead.

Is contact tracing on the scale the report suggests achievable in this country?

It's going to take a lot of work and some imagination and probably changing the rules in some ways to do things differently—but I do think it's achievable. We're seeing that other countries have implemented contact tracing and are able to contain the virus at a relatively low level in their communities.

We're also seeing parts of the U.S. start to put this in place, so that's encouraging, but it's not enough. We need to hire what we believe is up to 100,000 people or more to complete this work. So what we need first is funding and commitment from the federal government and Congress, to really scale this up in a way that's required. Our report suggests the need to dedicate approximately $3.6 billion for state and territorial health departments to make contact tracing wide-scale.

What are the likely outcomes if we try to reopen the country without robust contact tracing in place?

We don't know exactly how many people are still susceptible to COVID-19, but we're relatively confident that it's a very large percentage of our population. So if we reopen and we don't have the capacity to find each case, isolate them, then trace their contacts and put them in quarantine, this virus will start to circulate widely again in our communities, and we will see again a big surge of cases, a surge of hospitalizations, and a surge of deaths. If we don't reinforce these measures, things may get a lot worse.

As the report notes, privacy protections in the U.S. may prevent aspects of contact tracing we're seeing in other countries. What are the implications of that?

The U.S. won't be able to replicate a contact tracing effort like the one in South Korea, for example, which can use medical records, phone GPS records, credit card transactions, and closed-circuit TV.

We need to have conversations here about how to sufficiently protect privacy in this context. But there has to be a balance between personal privacy and getting health departments the information they need to act quickly. The Google and Apple partnership [to offer Bluetooth-enabled apps to track potential exposure to COVID-19] is promising, but it's unclear how public health officials will be able to use that information. I don't think we've struck that right balance yet with the technologies that are out there.

As unemployment skyrockets, to what extent can contact tracing create a new source of jobs?

This is a huge workforce that we need to engage. It may include many types of people: public health experts, retired health care workers, but also people outside the field. Contact tracing is an intensive activity, but it doesn't take a lot of time to train staff. We need people who are meticulous, who can make people comfortable and treat the task with sensitivity. Fluency in different languages is also a plus because we need to reach all communities.

So I think this is a great opportunity to put people to work who have either been laid off because of the pandemic, or who otherwise just want to be directly involved in the response.

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NZ needs COVID-19 contact tracing to make nationwide lockdown worthwhile

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More information: A National Plan to Enable Comprehensive COVID-19 Case Finding and Contact Tracing in the US.
https://www.centerforhealthsecurity.org/our-work/pubs_archive/pubs-pdfs/2020/200410-national-plan-to-contact-tracing.pdf

Provided by Johns Hopkins University

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Saliva samples preferable to deep nasal swabs for testing COVID-19

by Michael Greenwood, Yale University

Credit: CC0 Public Domain

As testing for the novel coronavirus continues to scale up, a new study finds that saliva samples are a "preferable" indicator for infection than the deep nasal swabs now widely used.

The study led by the Yale School of Public Health—and conducted at Yale New Haven Hospital with 44 inpatients and 98 health care workers—found that saliva samples taken from just inside the mouth provided greater detection sensitivity and consistency throughout the course of an infection than the broadly recommended nasopharyngeal (NP) approach. The study also concluded that there was less variability in results with the self-sample collection of saliva.

"Taken together, our findings demonstrate that saliva is a viable and more sensitive alternative to nasopharyngeal swabs and could enable at-home self-administered sample collection for accurate large-scale SARS-CoV-2 testing," said first author Anne Wyllie, an associate research scientist at the Yale School of Public Health and a member of its Public Health Modeling Unit. She was joined by 49 other researchers at Yale on the study.

The researchers also reported that the saliva approach detected SARS-CoV-2 in two asymptomatic health care workers who had previously tested negative for the virus in a NP swab test. Saliva testing may be especially useful due to its accuracy in identifying mild SARS-CoV-2 infections that are not detected with other methods, the researchers said.

More sensitive and consistent detection is expected to be critical in helping to assess when individuals are able to safely return to work and when local economies can reopen during the current pandemic.

The study has not been subject to peer review. The research results are currently available on the pre-print server medRxiv. The researchers called for the "immediate validation" of the results. Nasopharyngeal testing is considered the gold standard for detecting many upper respiratory tract pathogens.

The study noted that saliva is an appealing alternative to NP swabs because:

• Collecting saliva is minimally invasive to patients.
• Saliva samples can be reliably self-administered.
• Saliva has exhibited comparable sensitivity to nasopharyngeal swabs in detection of other respiratory pathogens.

The NP testing approach involves inserting a swab deep into the nostril and into the region of the pharynx. The swab is rotated to collect secretions and is then removed. The sample is then sent to a certified lab for analysis.

On April 13, the U.S. Food and Drug Administration gave emergency use authorization for a saliva-based test for COVID-19 developed by researchers at RUCDR Infinite Biologics, a biorepository backed by Rutgers University. The approved test must be conducted in a healthcare setting under supervision of a qualified professional.

"With further validation, widespread use of saliva sampling could be transformative for public health efforts," said Wyllie.

Saliva testing requires less resources, personal protective equipment, and personnel than nasopharyngeal swabbing, the researcher said.

"Once tests and laboratories are validated for using saliva, this could be rapidly implemented and immediately resolve many of the resource and safety issues with SARS-CoV-2 testing," said Nathan Grubaugh, an assistant professor at the Yale School of Public Health and one of the senior authors of the study.

COVID-19 saliva tests: What is the benefit?More information: Anne Louise Wyllie et al. Saliva is more sensitive for SARS-CoV-2 detection in COVID-19 patients than nasopharyngeal swabs, (2020). DOI: 10.1101/2020.04.16.20067835

Provided by Yale