July 6 marks World Zoonoses Day

How identifying hotspots of zoonotic disease could prevent another pandemic

Researchers have developed a tool to assess wildlife markets for risks of zoonotic outbreaks. It can help governments decide on courses of action, with strict veterinary requirements potentially more effective than bans.

The virus may have jumped from animal to human in a local wet market, such as this one in Wuhan

July 6 marks World Zoonoses Day, the anniversary of Louis Pasteur's first successful testing of his rabies vaccine on a human subject. As the coronavirus pandemic continues to rage across the globe, active measures are required to quell further outbreaks of zoonotic diseases.

For decades, scientists have been warning of dangerous zoonoses —zoonotic diseases caused by germs that spread between animals and people. From SARS to MERS and Ebola, many infectious diseases are transmitted by viruses that have an animal origin.

According to a report by the World Biodiversity Council, there are as many as 1.7 million undetected viruses in the animal kingdom, 827,000 of which could infect humans. As humans and wild animals come into ever closer contact, it is unlikely that COVID-19 is the last pandemic in our globalized world.
Wildlife trade with a potential for zoonotic diseases

Ever since the beginning of the coronavirus pandemic, there have been calls to strictly regulate or completely ban the trade in wild animals. Wildlife markets are considered to be potential "zoonotic hotspots" because different animal species are kept in close quarters, making it easy for dangerous viruses to spread.

A zoonosis is an infectious disease caused by a pathogen that has jumped from an animal to a human

Once it was clear that the new SARS CoV-2 virus had an animal origin, the World Health Organization (WHO) called for wild animal markets, which are particularly popular in Asia and Africa, to be shut down.

China, which faces particular criticism, temporarily banned the entire trade with wild animals in January 2020, to last until the COVID-19 pandemic is over. In the end, the ban did not last quite that long, with the markets now partially open again. Still, the trade with exotic animals and food in China has dropped significantly.
Wild animals important for food and medicines

Wild animals play an important cultural, traditional and even nutritional role for many people. Plans to ban the trade or consumption of wild animals in general are unrealistic; and in addition, strict bans are almost impossible to monitor, especially in regions with poor infrastructure or weak governance.

Watch video 12:00 COVID-19 Special: When animal diseases jump to humans

Regulating hygiene, or veterinary requirements for the trade and consumption of wild animals, might be a more effective strategy. This would also provide insight into the potential sources of danger.

Risk grids to identify hotspots

The World Wide Fund For Nature (WWF) has worked with scientists from Hong Kong to develop a tool to assess wildlife markets for future risks of zoonotic outbreaks. The risk matrix, published in the One Health scientific journal, will initially be used to analyze wildlife markets in the Asia-Pacific region. The sales situation in the respective market and the animal species or the number of wild animals traded are taken into account.

The team surveyed 46 wildlife markets in Laos and Myanmar. They showed a high zoonotic risk on about half of the days when the researchers made their observations.

It is clear that there are wildlife markets that always seem to have a high risk of zoonosis, said Stefan Ziegler, Senior Conservation Advisor Asia for the WWF and one of the authors of the study.
Strict veterinary requirements vs. ineffective bans

According to WWF, millions of wild animals are traded in the region each year for food or use in traditional medicine — including wild boar and deer, as well as rodents and bats, which are considered reservoirs for a variety of pathogens.

Wild boar and deer are also consumed in Germany. "However, the trade in these products is subject to strict veterinary regulations," as Ziegler told dpa news agency.

PHILIPPINES: STUDYING BATS MIGHT HELP PREVENT ANOTHER PANDEMIC

Casting their nets

The researchers, who call themselves "virus hunters," are out to catch thousands of bats for a simulation model. They hope that this will help them prevent another pandemic on the scale of the COVID-19 crisis in the future   1234567

Preventing zoonotic diseases a global job

Stopping the illegal and unregulated wildlife trade is just as important as monitoring wildlife markets, wildlife farms and restaurants where such meats are served, according to the environmental organization. In many places the relevant authorities, which are supposed to monitor the trade and enforce applicable law, are severely underfunded, the WWF added.

Pandemic protection is a global task, according to the WWF. The global community must provide targeted assistance in building national capacities for pandemic prevention, the international organization says — and the risk matrix could help minimize risks associated with the legal trade of wildlife.

Why are animal-to-human diseases on the rise?

Agence France-Presse
April 07, 2023

AFP
From Covid-19 to monkey pox, Mers, Ebola, avian flu, Zika and HIV, diseases transmitted from animals to humans have multiplied in recent years, raising fears of new pandemics.


What's a zoonosis?

A zoonosis (plural zoonoses) is a disease or infection transmitted from vertebrate animals to people, and vice versa. The pathogens involved can be bacteria, viruses or parasites.

These diseases are transmitted either directly during contact between an animal and a human, or indirectly through food or through a vector such as an insect, spider or mite.

Some diseases end up becoming specifically human, like Covid-19.

According to the World Organisation for Animal Health, 60 percent of human infectious diseases are zoonotic.

What types of diseases are involved?

The term "zoonoses" includes a wide variety of diseases.

Some affect the digestive system, such as salmonellosis, others the respiratory system, such as avian and swine flu as well as Covid, or the nervous system in the case of rabies.

The severity of these diseases in humans varies greatly depending on the disease and the pathogen's virulence, but also on the infected person, who may have a particular sensitivity to the pathogen.

What animals are involved?

Bats act as a reservoir for many viruses that affect humans.

Some have been known for a long time, such as the rabies virus, but many have emerged in recent decades, such as Ebola, the SARS coronavirus, Sars-CoV-2 (which causes Covid-19) or the Nipah virus, which appeared in Asia in 1998.

Badgers, ferrets, mink and weasels are often implicated in viral zoonoses, and in particular those caused by coronaviruses.

Other mammals, such as cattle, pigs, dogs, foxes, camels and rodents, also often play the role of intermediate host.

All the viruses responsible for major influenza pandemics had an avian origin, either direct or indirect.

Finally, insects such as ticks are vectors of many viral diseases that affect humans.

- Why has the frequency of zoonoses increased?

Having appeared thousands of years ago, zoonoses have multiplied over the past 20 or 30 years.

The growth of international travel has allowed them to spread more quickly.

By occupying increasingly large areas of the planet, humans also contribute to disrupting the ecosystem and promoting the transmission of viruses.

Industrial farming increases the risk of pathogens spreading between animals.

Trade in wild animals also increases human exposure to the microbes they may carry.

Deforestation increases the risk of contact between wildlife, domestic animals and human populations.

Should we fear another pandemic?

Climate change will push many animals to flee their ecosystems for more livable lands, a study published by the scientific journal Nature warned in 2022.

By mixing more, species will transmit their viruses more, which will promote the emergence of new diseases potentially transmissible to humans.

"Without preventative strategies, pandemics will emerge more often, spread more rapidly, kill more people, and affect the global economy with more devastating impact than ever before," the UN Biodiversity Expert Group warned in October 2020.

According to estimates published in the journal Science in 2018, there are 1.7 million unknown viruses in mammals and birds, 540,000 to 850,000 of them with the capacity to infect humans.

But above all, the expansion of human activities and increased interactions with wildlife increase the risk that viruses capable of infecting humans will "find" their host.

© 2023 AFP

ZOONOSIS

Fuzzy, Cute, and ... Viral? Bats A Likely Source Of Future Pandemics

William A. Haseltine
FORBES
Jan 20, 2024


Flying bat hunting in forest. The grey long-eared bat (Plecotus austriacus) is a fairly large ... [+]GETTY

One of the many lessons from our —ongoing— battle with Covid-19 is that viral transfer from wild animals to humans, known as zoonosis, is a very real threat. And this isn’t the first time it’s happened: SARS-CoV-1, AIDS, and Ebola can all be put into the same category. Indeed, roughly 60% of epidemics can be traced back to an animal origin. The thing is, the sources of zoonotic diseases aren't always “exotic” animals that only infrequently come into contact with humans. One of the major zoonotic culprits is markedly more quotidian: bats. Viral spillover from these furry vampires leads to higher fatality rates than spillover events from other animals. Why is that? A new study published in PLOS Biology suggests it may all be in the wings.

Predicting Animal Spillovers

Although entirely preventing zoonotic spillovers will be difficult, we can strive to strengthen our public health systems to help minimize the effect of future occurrences. A key part of this process is honing our understanding of the threats. Which animal populations present the largest risk? Which taxonomic orders give rise to the most virulent viruses? In effect, where should we be looking?

One shorthand approach has been to focus on phylogenetic relationships, which describe how closely or how distantly different animals are related to one another based on their evolutionary history. In general, spillover events across animal orders that are more distantly related to one another lead to high viral virulence. Note that increased viral virulence doesn’t always mean increased overall mortality: if a virus is too virulent, it kills off its host before it has a chance to transmit to a new host. This is known as trade-off theory. So, the animal populations most likely to saddle us with virulent viruses are not necessarily those most likely to saddle us with pandemics. Still, as evidenced by Ebola and SARS-CoV-2, unlikely and impossible are two different things.

Though a useful heuristic, phylogenetic relationships don’t completely predict the virulence of spillover events. Think of it as a very coarse sieve — it filters out the largest debris but fails to capture a lot of the smaller particles. The researchers, by collecting data from a large number of spillover studies and generating a statistical model, set out to provide a finer sieve. In particular, they wanted to pinpoint the features of bat immune systems that predispose them to becoming viral reservoirs. Other animals with similar immune systems, it would stand to reason, may pose a similar risk.

Flight and Inflammation: What’s the Connection?

Bats are masters at hosting viruses while remaining mostly unaffected by their presence. This includes viruses which, in other animals, would usually cause serious disease or death. They are also extremely adept at keeping viral load —the total amount of virus present in an organism— low. In some sense, bats are perfect viral incubators; they provide viruses with a home to reproduce and evolve, all free of charge. That’s why bat viruses that make the transition into human hosts are often so deadly, they’ve had years to improve overall fitness.

How is it that the bats themselves are not affected by the viruses? Well, bats are the only winged mammals — all other animals of flight are either insects or birds. And flight is not an easy thing. It is extremely taxing at the metabolic level, requiring a great deal of effort and energy. So much so that it causes oxidative stress, which happens when oxygen-containing molecules build up more quickly than the body’s ability to break them down. Left unaddressed, this can cause DNA damage and chronic inflammation. But if every time a bat took flight its inflammatory response kicked in, it would be in a constant state of inflammation. This is, of course, far from optimal. A little inflammation is crucial to healing, yes, but too much of it will end up harming otherwise healthy tissues and organs. To avoid this, bats seem to have developed a heightened tolerance for inflammation. In short, it takes a great deal to trigger a bat’s inflammatory response.

At the genetic level, these adaptations are reflected by decreased activation or wholesale loss of many of the genes associated with inflammation. These include heavy hitters like NLRP3 (NLR family pyrin domain containing 3) and other genes involved in an important inflammatory signaling pathway called NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells)

So while the increased tolerance to inflammation likely evolved to help bats fly, it also had the added benefits of boosting their longevity —bats are extraordinarily long-lived relative to their body size— and of letting them come away from viral infections mostly unscathed. Combined, this makes bats an excellent breeding ground for new viruses: their inflammatory response is rarely triggered by circulating viruses, giving the viruses a chance to replicate and mutate undisturbed. And since bats aren’t usually affected by the viruses they carry, the viruses can crank up the dial on virulence without fear of killing their hosts. A foolproof recipe for dangerously fit viruses.

Bats and Antiviral Genes

A recent study also discovered that horseshoe bats lack an antiviral variant of a gene called OAS1 (2'-5'-oligoadenylate synthetase 1). In humans, the OAS1 gene comes in two different forms, one short and the other long. During the height of the pandemic, researchers noticed that the majority of patients hospitalized with Covid-19 carried the shorter variant of the gene. Follow-up experiments revealed that the longer variant of the gene included vital information that helped carriers’ immune systems identify and destroy the RNA of SARS-CoV-2.

How? The protein produced by the longer gene variant carries a signal that allows it to be modified by the addition of a fat molecule, a process called prenylation. The addition of the fat molecule lets the OAS1 protein associate with cellular membranes. A common tactic employed by SARS-CoV-2, and other such viruses, is to “cloak” itself in a specialized replication compartment called a double-membrane vesicle. This compartment allows the virus to hide its RNA from our immune system. The longer version of OAS1, however, cuts through this viral tactic; by binding to cellular membranes, it can penetrate the replication compartment, locate the viral RNA, and sound the alarm bells.

As it turns out, horseshoe bats lack the protective version of the gene. At some point in time, they “lost” the variant to evolution. Instead, they only have the shorter version, which doesn’t offer any antiviral benefits. Why the bats lost the protective variant of the gene remains unclear, and what the current version of the gene does is equally unknown. A reasonable guess would be that the loss of the protective variant is part of the general trend towards an increased tolerance of inflammation, but more work needs to be done to piece together this particular puzzle.

Takeaways

This study provides us with a new, more fine-tuned way of predicting future viral spillover events. In particular, it helps direct our gaze to those mammals most likely to saddle us with highly virulent viruses. By studying bats, a well-known source of zoonotic outbreaks, the researchers managed to pinpoint key features that prefigure the evolution of quickly replicating viruses: hosts with protracted lifespans for their body size, which often indicates a heightened tolerance for inflammation, and hosts with strong constitutive immune responses. Viral tolerance, which is the ability to be exposed to high viral loads without suffering health consequences, is especially relevant to the development of virulent viruses.

The findings also raise an interesting question regarding the role and helpfulness of inflammation. Clearly, some degree of inflammation is necessary for successful immune function, but if bats are anything to go by, the less inflammation the better. Despite being chock full of viruses, they often suffer no adverse health effects. They also live long and healthy lives. Indeed, persistent inflammation is considered a hallmark of aging in humans. Excessive inflammation is also linked to numerous disorders in humans. Perhaps the bats are onto something.

Of course, as is the case for any model, we need to take the results with a grain of salt. A model is only as accurate as the data it is based on. The more data, and the better the quality of the data, the better the predictions of the model. Still, the model the researchers generated has provided useful hypotheses that can now be experimentally tested, both in cell culture and in vivo.

Follow me on Twitter or LinkedIn. 

William A. Haseltine

I am a scientist, businessman, author, and philanthropist. For nearly two decades, I was a professor at Harvard 

CIA 'looking into' allegations connected to COVID-19 origins

SASHA PEZENIK

Wed, September 13, 2023

The Central Intelligence Agency (CIA) confirms to ABC News it is "looking into" accusations that several members of an agency team tasked with COVID-19 pandemic analysis were paid off "significant" hush money in order to buy a shift in their position about where the virus came from -- but the agency emphasized it does not pay its analysts to reach particular conclusions.

"At [the] CIA we are committed to the highest standards of analytic rigor, integrity and objectivity. We do not pay analysts to reach specific conclusions," CIA spokesperson Tammy Kupperman Thorp said in a statement to ABC News. "We take these allegations extremely seriously and are looking into them. We will keep our Congressional oversight committees appropriately informed."

The CIA's comment and review come in response to claims leveled in a new letter from two Republican House chairmen to CIA Director Bill Burns, sent Tuesday, which says there is a whistleblower within current, senior ranks of the agency, making these allegations.

It's the latest chapter in the yet-unresolved contentious debate over the origins of the COVID-19 pandemic -- and the latest in an ongoing effort by the GOP to find evidence suggesting that COVID's origins have been buried by a conspiratorial cover-up.

In their letter to Director Burns, chair of the Select Subcommittee on the Coronavirus Pandemic, Brad Wenstrup (R-OH), and chairman of the Permanent Select Committee on Intelligence Chairman, Mike Turner (R-OH), say a "multi-decade, senior-level, current CIA officer" had come forward alleging the payoff.

MORE: US intelligence report on COVID-19 origins rejects some points raised by lab leak theory proponents

Turner and Wenstrup's missive came as an apparent surprise to the other side of the aisle on their respective committees.

"Neither the ranking member nor the Democratic staff for the Intelligence Committee were made aware of these allegations before the letters were sent. We have requested additional information," a spokesperson for the Democrats on the House Permanent Select Committee on Intelligence said in a statement to ABC News.

A spokesperson for Select Subcommittee Democrats said they "were given no prior notice of a whistleblower's existence, let alone testimony," adding that "without further information regarding this claim from the Majority, we have no ability to assess the allegations at this time."

According to the whistleblower, seven "multi-disciplinary and experienced officers with significant scientific expertise" had been assigned to a "COVID discovery team," Wenstrup and Turner's letter says.

At the end of their review, all but one member of that team leaned towards a lab leak origin -- but that they were "given a significant monetary incentive to change their position," according to the letter stating the whistleblower's allegations.

"Six of the seven members of the team believed the intelligence and science were sufficient to make a low confidence assessment that COVID-19 originated from a laboratory in Wuhan, China," the letter said.

"The seventh member of the team, who also happened to be the most senior, was the lone officer to believe COVID-19 originated through zoonosis," the letter said. "The whistleblower further contends that to come to the eventual public determination of uncertainty, the other six members were given a significant monetary incentive to change their position."

Ultimately, as the Office of the Director of National Intelligence said in June, the CIA and "another agency" remained "unable" to decide on where they think COVID's origins lie, as "both hypotheses rely on significant assumptions or face challenges with conflicting reporting."

MORE: Hunting COVID's origins: New intelligence and scientific reports shift debate

As ABC reported at the time, the Department of Energy and the FBI believe with varying degrees of confidence that a lab incident was the "most likely" cause of the first human infection, though ODNI said it arrived at that conclusion "for different reasons."

ODNI also underscored that "almost all" the agencies didn't believe the virus was genetically engineered and "most agencies" don't think the virus was lab-adapted -- meaning, most of the U.S. intelligence community doesn't think that so-called "gain-of-function" research was how COVID-19 was born.

No definitive conclusion as to COVID's origins has yet been determined by the American intelligence or international public health bodies who have probed for answers. And, as ODNI, President Biden and international health bodies have emphasized, unless Beijing stops stonewalling the investigation into COVID's origins, no more definitive conclusion will be possible.

Wenstrup and Turner have asked for a number of documents on the team's creation -- their intra group, intra agency and inter agency communications on COVID's origins, and records of payments or financial bonuses made to members of the team. Wenstrup and Turner want them by Sept. 26.

In a separate letter, Wenstrup and Turner also invite former CIA chief operating officer Andrew Makridis to sit for a "voluntary transcribed interview" on that same day, saying he "played a central role" in the "formation and eventual conclusion" of the team the whistleblower pointed to.

A spokesperson for the Select Subcommittee on the Coronavirus Pandemic had no further comment at this time. There's no hearing currently scheduled.

LA REVUE GAUCHE - Left Comment: Search results for COVID CHINA CONSPIRACY 

Mink pass coronavirus to humans in the Netherlands
IT CALLED ZOONOSIS FOR A REASON
At least two people have caught the coronavirus from mink in the Netherlands, in probably the first mink-to-human transmission cases. The risk of infection outside mink farms is "negligible," Dutch officials said.


The Dutch government on Monday said that it was "highly likely" that a person had been infected with the coronavirus by a mink, following a similar case last week.

Mink are bred for their fur at some 155 farms across the country. The authorities detected infected animals at four such locations, Agriculture Minister Carola Schouten said in a letter to parliament. At three out of four farms, a sick human was thought to be the source of the infection among the animals, while officials were still investigating the cause at the fourth one, the minister said.


Several mink farms in the Netherlands have noted human-to-mink transmission, the reverse is rarer

The mink farms are set to close in 2023 due to a law passed before the coronavirus outbreak. Amid the latest developments, some veterinarians accused Schouten of trying to downplay the risk of the animal-to-human infection and pressured the government to clear out heavy-hit farms. However, Schouten has so far rejected the push. Addressing Dutch lawmakers on Monday, Schouten said the risk of humans getting infected outside farms was "negligible."

Dutch pets confirmed infected

Reports of humans infecting their animals, particularly cats and dogs, have appeared in various countries across the world since the beginning of the current pandemic. At least four house pets tested positive in the Netherlands last month. Minister Schouten has urged COVID-19 patients to "avoid contact with their animals."

However, the latest mink-to-human transmission was virtually unique, said the head of the country's health insitute, Jaap van Dissel, on Monday.

"This is the first time we've found, at least we've shown that it's likely, that in two cases the infection has gone from animal to human," he said. "Of course the original source of infection in China was also very likely animals," he added.

dj/msh (dpa, Reuters)

Bats and Viruses - Journal of Wildlife Diseases

https://www.jwildlifedis.org › doi › pdf

by AT Gilbert - ‎2017 - ‎Related articles

Book reviews express the opinions of the individual authors regarding the value of the book's ... zoonosis. The potential for aerosol transmis- sion of rabies virus from massive aggregations ... the recent popular book Spillover (Quammen.

Zoonoses 3 Prediction and prevention of the next pandemic zoonosis THE LANCET DECEMBER 1, 2012
Stephen S Morse, Jonna A K Mazet, Mark Woolhouse, Colin R Parrish, Dennis Carroll, William B Karesh, Carlos Zambrana-Torrelio, W Ian Lipkin, Peter Daszak
Most pandemics—eg, HIV/AIDS, severe acute respiratory syndrome, pandemic infl uenza—originate in animals, are caused by viruses, and are driven to emerge by ecological, behavioural, or socioeconomic changes. Despite their substantial eff ects on global public health and growing understanding of the process by which they emerge, no pandemic has been predicted before infecting human beings. We review what is known about the pathogens that emerge, the hosts that they originate in, and the factors that drive their emergence. We discuss challenges to their control and new eff orts to predict pandemics, target surveillance to the most crucial interfaces, and identify prevention strategies. New mathematical modelling, diagnostic, communications, and informatics technologies can identify and report hitherto unknown microbes in other species, and thus new risk assessment approaches are needed to identify microbes most likely to cause human disease. We lay out a series of research and surveillance opportunities and goals that could help to overcome these challenges and move the global pandemic strategy from response to pre-emption.


Brazilian Journal of Infectious DiseasesPrint version ISSN 1413-8670On-line version ISSN 1678-4391
Braz J Infect Dis vol.22 no.1 Salvador Jan./feb. 2018
https://doi.org/10.1016/j.bjid.2017.11.003

LETTERS TO THE EDITOR

Zoonotic spillover and emerging viral diseases – time to intensify zoonoses surveillance in Brazil
Joel Henrique Ellwanger1
José Artur Bogo Chies* 1

1Laboratório de Imunobiologia e Imunogenética, Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil

Dear Editor:
Are we prepared to face newly emerging viral diseases? This question is as recurrent as the emergence of new viruses and the reemergence of neglected infectious diseases. Of note, Central and South America are considered world hotspots for the emergence of new mammalian viral zoonoses.1 Due to the size of its territory, Brazil lies at the center of these hotspots.

Zoonotic Diseases of Public Health Importance - NCDC

https://ncdc.gov.in › WriteReadData › File618

new and emerging zoonotic diseases, like Ebola, Zika Virus Disease and ... Besides serving as a reference book, the ... situation-report-12-02-2016.pdf).

UP TO DATE REFERENCE MANUAL FROM INDIA 2016

A brief guide to emerging infectious diseases and zoonoses
A brief guide to emerging infectious diseases and zoonoses.
1. Communicable Diseases, Emerging
2. Zoonoses – epidemiology – prevention and control.
3. Virus Diseases.
4. Bacterial Infections. 
5. Parasitic Diseases. 
6. Pest Control
ISBN 978-92-9022-458-7(NLM classification: WA 110

© World Health Organization 2014
All rights reserved.Requests for publications, or for permission to reproduce or translate WHO publications – whether for sale orfor noncommercial distribution – can be obtained from SEARO Library, World Health Organization, RegionalOffice for South-East Asia, Indraprastha Estate, Mahatma Gandhi Marg, New Delhi 110 002, India (fax: +91 1123370197; e-mail: searolibrary@who.int).

 

How a plant based diet could prevent the next Covid 19 Pandemic

AND SAVE THE PLANET TOO

24 May, 2021 01:23 PM

"Not a single pandemic in human history has been traced to plants." Photo / Getty Images

Other

By: The Conversation - Kurtis Boyer

Kurtis Boyer, Faculty Lecuture, Johnson-Shoyama Graduate School of Public Policy, University of Saskatchewan

Viruses like Covid-19, SARS, bovine spongiform, swine flu and avian flu all have something in common: They all come from animals, described by scientists as zoonotic diseases.

Yet, these diseases do not really "come from animals". After all, it is not like animals conspire against humans, throwing Covid-19 over the backyard fence. When we say this pandemic "comes from animals", it means that these diseases come from the way society raises, harvests and eats animals.

A well-rounded policy strategy for avoiding the next pandemic should include reducing the demand for animal products. Fortunately, an effective approach need not imply the government telling people what they should or should not eat.

Many people are already aware of the benefits of a plant-based diet. Doing a better job at supporting those already trying to make a dietary change could be an effective approach for government policy

Zoonosis and food production

The fact that a growing list of pandemics originate exclusively within the animal and agricultural sectors is nothing new to a small but growing group of independent scientists. The United Nations recently voiced a similar concern.

In its report, Preventing the Next Pandemic: Zoonotic diseases and how to break the chain of transmission, the UN laid out some of the things needed for improving health governance in relation to food production.

Some of the policy options include expanding scientific inquiry into the environmental dimensions of zoonotic diseases and developing and implementing stronger biosecurity measures. It calls for policies that strengthen animal health (including wildlife health services) and increased capacity in monitoring and regulating food production.

Policies that strengthen animal health and increase monitoring and regulation in food production may reduce the risk of zoonotic diseases. Photo / Getty Images

The report also recommends that states find ways to reduce demand for animal protein. Reducing the demand for meat is not something we often hear as a possible policy option — partly because people may not link our current pandemic to the western diet or agricultural sector.

Origins of a pandemic

Early cases of Covid-19 were linked to markets in China where wild animals were sold. Pangolins and bats have been identified as possible sources of infection, neither of which is on the shopping lists of the average global consumer. The deeper roots of this pandemic, however, are more complicated.

Many earlier viruses have originated in the animal husbandry industrial production chain.

• <p>In the 1980s the <a href="https://www.bbc.com/news/uk-45906585">United Kingdom's cattle production began to see outbreaks of Bovine spongiform encephalopathy</a> (mad cow disease), and <a href="https://www.newscientist.com/article/2118418-many-more-people-could-still-die-from-mad-cow-disease-in-the-uk/">its human equivalent variant Creutzfeldt–Jakob disease</a>. </p>
• <p>In <a href="https://web.archive.org/web/20051129155319/http://www.who.int/csr/disease/avian_influenza/Timeline_28_10a.pdf">1997, the bird flu (H5N1) was traced to chicken factories in China</a>. </p>
• <p>In 2009, <a href="https://virologyj.biomedcentral.com/articles/10.1186/1743-422X-6-207">the swine flu (H1N1) originated in pig farms in Mexico </a> and <a href="https://www.wired.com/2009/05/swineflufarm/">North Carolina in the United States</a>. </p>
• <p>More recently, a possible <a href="https://www.who.int/csr/don/06-november-2020-mink-associated-sars-cov2-denmark/en/">new strain of Covid-19 has been found in farms in Denmark</a>, where mink are raised for fur coats.</p>

It is clear that the origins of these pandemics are not restricted to certain countries or certain practices, such as "wet-markets." For some researchers, including Swedish chief physician and infectious diseases professor Björn Olsen, stemming rising demand for meat and dairy is a necessary part of reducing our risk for pandemics.

Olsen, who is well known for being an early critic of his government's Covid-19 response, is now becoming known for another early warning — one he has been making in books and articles for nearly 10 years now. In a recent interview in Swedish, Olsen notes that pandemic viruses have all arisen where animals and humans meet, and raising billions of animals as food will have effects.

Consider all this in reverse: not a single pandemic in human history has been traced to plants.

While strengthening regulatory and monitoring capacity is an important part of an effective policy strategy, when societies replace animal sources of food with plant-based foods, they also reduce the risk of future pandemics. Olsen worries the link between the rising demand for animal protein and pandemics is not getting enough attention from politicians.

Plant-based diet as policy

A reason why politicians might not see a move towards a plant-based diet as a viable policy option could be because it relies on changing peoples' behaviour, and some would argue that governments should not be in the business of trying to impose dietary choices. Yet there is good reason to think that people are already open to transitioning to a plant-based diet.

According to a recent UN survey, 30 per cent of the world supports a plant-based diet as a climate policy. In fact, nearly 10 per cent of Canada's total population is already vegan or vegetarian, according to a 2018 study led by Sylvain Charlebois, a professor of food distribution and policy at Dalhousie University. The number of people attempting to eat plant-based diets is growing fast. In an interview, Charlebois noted:

With these changes in dietary preferences already occurring, governments need look no further than removing barriers for people to continue to make up their own minds. To support their transition and reduce the demand in animal products, the government should do its best to reduce what many could perceive as the inconvenience of a plant-based diet.

This could begin by reviewing food procurement and nutrition standards to ensure that public facilities such as schools, hospitals, prisons and care homes offer a plant-based meal as standard on menus every day.

Food guide focus

Government should also look to put its own food guide in practice and make plant-based foods more accessible, including for low-income, rural and northern residents. When the Canadian government revised Canada's food guide in 2019, it consulted extensively with nutritionists and scientists. The result was an increased focus on plants as sources of protein, and a reduction of emphasis on meat and dairy.

Canada's food guide tells us to "choose protein foods that come from plants more often." Yet, despite this and the fact that consumption has been in steady decline in Canada since 2009, fresh milk still receives the highest level of subsidies within the Nutrition North Canada subsidy — a federal programme that aims to ensure adequate nutrition in the North. A move is needed to subsidise foods that are good for people and the planet.

We know that dietary habits have environmental impact as well as health impact. Given that there is also a clear link between the consumption of animal products and zoonotic diseases, there is further reason for policy makers to support people who want to shift to a plant-based diet.

It's not too soon to start trying to prevent the next pandemic; experts warn it could arrive at any time. Since the 2003 SARS epidemic, the time between outbreaks of zoonotic viruses has been getting shorter, it's not a question of if there will be another pandemic, but when.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Vikings had smallpox and may have helped spread the world's deadliest virus

Summary:Scientists have discovered extinct strains of smallpox in the teeth of Viking skeletons -- proving for the first time that the killer disease plagued humanity for at least 1400 years.

Date:July 23, 2020

Source:St John's College, University of Cambridge

FULL STORY

Viking ship (stock image).
Credit: © Alex Stemmer / stock.adobe.com

Scientists have discovered extinct strains of smallpox in the teeth of Viking skeletons -- proving for the first time that the killer disease plagued humanity for at least 1400 years.

Smallpox spread from person to person via infectious droplets, killed around a third of sufferers and left another third permanently scarred or blind. Around 300 million people died from it in the 20th century alone before it was officially eradicated in 1980 through a global vaccination effort -- the first human disease to be wiped out.

Now an international team of scientists have sequenced the genomes of newly discovered strains of the virus after it was extracted from the teeth of Viking skeletons from sites across northern Europe. The findings have been published in Science today (July 23, 2020).

Professor Eske Willerslev, of St John's College, University of Cambridge, and director of The Lundbeck Foundation GeoGenetics Centre, University of Copenhagen, led the study.

He said: "We discovered new strains of smallpox in the teeth of Viking skeletons and found their genetic structure is different to the modern smallpox virus eradicated in the 20th century. We already knew Vikings were moving around Europe and beyond, and we now know they had smallpox. People travelling around the world quickly spread Covid-19 and it is likely Vikings spread smallpox. Just back then, they travelled by ship rather than by plane.

"The 1400-year-old genetic information extracted from these skeletons is hugely significant because it teaches us about the evolutionary history of the variola virus that caused smallpox."

Smallpox was eradicated throughout most of Europe and the United States by the beginning of the 20th century but remained endemic throughout Africa, Asia, and South America. The World Health Organisation launched an eradication programme in 1967 that included contact tracing and mass communication campaigns -- all public health techniques that countries have been using to control today's coronavirus pandemic. But it was the global roll out of a vaccine that ultimately enabled scientists to stop smallpox in its tracks.

Historians believe smallpox may have existed since 10,000 BC but until now there was no scientific proof that the virus was present before the 17th century. It is not known how it first infected humans but, like Covid-19, it is believed to have come from animals.

Professor Martin Sikora, one of the senior authors leading the study, from the Centre for GeoGenetics, University of Copenhagen, said: "The timeline of the emergence of smallpox has always been unclear but by sequencing the earliest-known strain of the killer virus, we have proved for the first time that smallpox existed during the Viking Age.

"While we don't know for sure if these strains of smallpox were fatal and caused the death of the Vikings we sampled, they certainly died with smallpox in their bloodstream for us to be able to detect it up to 1400 years later. It is also highly probable there were epidemics earlier than our findings that scientists have yet to discover DNA evidence of."

The team of researchers found smallpox -- caused by the variola virus -- in 11 Viking-era burial sites in Denmark, Norway, Russia, and the UK. They also found it in multiple human remains from Öland, an island off the east coast of Sweden with a long history of trade. The team were able to reconstruct near-complete variola virus genomes for four of the samples.

Dr Lasse Vinner, one of the first authors and a virologist from The Lundbeck Foundation GeoGenetics Centre, said: "Understanding the genetic structure of this virus will potentially help virologists understand the evolution of this and other viruses and add to the bank of knowledge that helps scientists fight emerging viral diseases.

"The early version of smallpox was genetically closer in the pox family tree to animal poxviruses such as camelpox and taterapox, from gerbils. It does not exactly resemble modern smallpox which show that virus evolved. We don't know how the disease manifested itself in the Viking Age -- it may have been different from those of the virulent modern strain which killed and disfigured hundreds of millions."

Dr Terry Jones, one of the senior authors leading the study, a computational biologist based at the Institute of Virology at Charité -- Universitätsmedizin Berlin and the Centre for Pathogen Evolution at the University of Cambridge, said: "There are many mysteries around poxviruses. To find smallpox so genetically different in Vikings is truly remarkable. No one expected that these smallpox strains existed. It has long been believed that smallpox was in Western and Southern Europe regularly by 600 AD, around the beginning of our samples.

"We have proved that smallpox was also widespread in Northern Europe. Returning crusaders or other later events have been thought to have first brought smallpox to Europe, but such theories cannot be correct. While written accounts of disease are often ambiguous, our findings push the date of the confirmed existence of smallpox back by a thousand years."

Dr Barbara Mühlemann, one of the first authors and a computational biologist, took part in the research during her PhD at the Centre for Pathogen Evolution at the University of Cambridge, and is now also based at the Institute of Virology at Charité, said: "The ancient strains of smallpox have a very different pattern of active and inactive genes compared to the modern virus. There are multiple ways viruses may diverge and mutate into milder or more dangerous strains. This is a significant insight into the steps the variola virus took in the course of its evolution."

Dr Jones added: "Knowledge from the past can protect us in the present. When an animal or plant goes extinct, it isn't coming back. But mutations can re-occur or revert and viruses can mutate or spill over from the animal reservoir so there will always be another zoonosis."

Zoonosis refers to an infectious disease outbreak caused by a pathogen jumping from a non-human animal to a human.

The research is part of a long-term project sequencing 5000 ancient human genomes and their associated pathogens made possible thanks to a scientific collaboration between The Lundbeck Foundation, The Wellcome Trust, The Nordic Foundation, and Illumina Inc.

Professor Willerslev concluded: "Smallpox was eradicated but another strain could spill over from the animal reservoir tomorrow. What we know in 2020 about viruses and pathogens that affect humans today, is just a small snapshot of what has plagued humans historically."
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Story Source:

Materials provided by St John's College, University of Cambridge. Note: Content may be edited for style and length.


Journal Reference:
Barbara Mühlemann, Lasse Vinner, Ashot Margaryan, Helene Wilhelmson, Constanza De La Fuente Castro, Morten E. Allentoft, Peter De Barros Damgaard, Anders Johannes Hansen, Sofie Holtsmark Nielsen, Lisa Mariann Strand, Jan Bill, Alexandra Buzhilova, Tamara Pushkina, Ceri Falys, Valeri Khartanovich, Vyacheslav Moiseyev, Marie Louise Schjellerup Jørkov, Palle Østergaard Sørensen, Yvonne Magnusson, Ingrid Gustin, Hannes Schroeder, Gerd Sutter, Geoffrey L. Smith, Christian Drosten, Ron A. M. Fouchier, Derek J. Smith, Eske Willerslev, Terry C. Jones, Martin Sikora. Diverse variola virus (smallpox) strains were widespread in northern Europe in the Viking Age. Science, 2020 DOI: 10.1126/science.aaw8977


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St John's College, University of Cambridge. "Vikings had smallpox and may have helped spread the world's deadliest virus." ScienceDaily. ScienceDaily, 23 July 2020. .

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