overview
- This year, the bird flu outbreak has led to several alarming developments, with at least 64 human infections.
- Experts outlined several indicators that the spread of the virus is moving in the wrong direction.
- These include the recent detection of the virus in wastewater and signs of dangerous mutations.
The lingering threat of bird flu appears to be escalating.
This year has witnessed a series of troubling events related to the virus spread. Since April, at least 64 individuals have tested positive for the virus, marking the first U.S. case in 2022 apart from one. Dairy herds in 16 states were affected this year. The Centers for Disease Control and Prevention confirmed the nation’s first severe case of avian influenza in a critically ill patient in Louisiana. California Governor Gavin Newsom declared a state of emergency this week due to the growing outbreak in cattle and poultry.
“The warning signs are transitioning from green to yellow,” stated Dr. Peter Chin-Hong, a professor of medicine at the University of California, San Francisco specializing in infectious diseases. “Numerous indications are pointing in an unfavorable direction.”
While no human-to-human transmission of avian influenza has been recorded, the CDC asserts that the immediate public health risk remains low. However, concerns are escalating based on four key indicators.
For instance, the avian influenza virus known as H5N1 is rapidly spreading among animals, including cattle, that frequently interact with humans. Moreover, detections in wastewater suggest that the virus has not only impacted livestock but also various other areas.
Additionally, there are instances of human cases where the source of infection is unidentified, along with studies on the virus’s evolution indicating that it has adapted to human receptors required for inter-human transmission. Fewer mutations have been observed.
Experts warn that when considering these indicators together, the virus is on track to potentially become the next pandemic.
“We are currently in a very precarious situation,” remarked Scott Hensley, a microbiology professor at the University of Pennsylvania.
Extensive circulation creates new pathways to humans
Since the onset of the avian influenza outbreak in 2022, the virus has spread to wild birds, domestic poultry, and wild mammals like sea lions, foxes, and black bears. Over 125 million poultry have perished from infectious diseases or been culled in the United States, as per the U.S. Department of Agriculture.
In March, an unexpected occurrence unfolded when dairy cows fell ill, experienced reduced feed intake, and produced discolored milk.
Research indicates that the virus likely spread swiftly and effectively among cows through raw milk, as infected cows excreted significant virus amounts from their mammary glands. Raccoons and domestic cats are also susceptible if they consume raw milk.
The more animals infected, the higher the risk of transmission to humans who come in contact with them.
“The more individuals infected, the higher the likelihood of variant emergence,” mentioned Jennifer Nuzzo, an epidemiology professor and head of the Pandemic Center at Brown University’s School of Public Health. “I don’t want to give the virus the opportunity to trigger a pandemic.”
Prior to this year, influenza prevention efforts did not focus on cows.
“We hadn’t considered dairy cows to be influenza hosts, at least not significant ones,” mentioned Andrew Bowman, a veterinary preventive medicine professor at Ohio State University in an interview with NBC News this past summer.
However, the virus has been detected in at least 865 herds in 16 states and in raw (unpasteurized) milk sold in California. For domestic cats that consume raw milk.
“Currently, raw milk and related products pose a direct risk to communities and consumers,” stated Chin-Hong. “A year ago, or even just months ago, the risk was significantly lower.”
Cases with unknown exposure sources
Most human H5N1 infections occur among poultry and dairy farm workers. However, in some mysterious instances, the source of infection remains unidentified.
One such case was reported in Hospital in Missouri in August, with subsequent recovery. Another instance involved children in California who tested positive in November.
Furthermore, Delaware health authorities reported a case of H5N1 infection this week in an individual with no known exposure to poultry or cattle. Although CDC testing did not confirm avian influenza as the virus, the case is considered “probable.”
In British Columbia, Canada, a teenager was hospitalized in early November after contracting H5N1 despite no apparent contact with farm animals or wildlife. The genetic makeup of the virus suggested similarity to strains found in waterfowl and poultry.
Such unexplained cases are causing concern among experts.
“This implies that the virus has a wider reach, and more individuals may have encountered it than previously thought,” mentioned Nuzzo.
Increased concentration of avian influenza in wastewater
Scientists are actively monitoring wastewater for virus fragments to better comprehend the geographical spread of the avian influenza epidemic.
Amy Lockwood, CDC’s director of public health partnerships and Verily, a company offering CDC wastewater testing services, stated that in recent months, “detections are increasing in frequency across a broader geographic spectrum.” A program known as Wastewater SCAN is in place.
Earlier in the month, approximately 19% of facilities monitored within the CDC’s National Wastewater Surveillance System across at least 10 states reported positive detections.
It is uncertain whether the detected virus fragments originated from animals or humans. For instance, some may stem from wild bird droppings entering storm drains.
“At this stage, we do not believe these signify human-to-human transmission, but there are numerous H5 viruses present,” revealed Peggy, CDC’s Director of Infectious Disease Control and Innovation.
Lockwood and Peggy mentioned that wastewater detections are concentrated near dairy processing facilities and poultry farms. However, puzzling hotspots have emerged in regions devoid of such agricultural operations in recent months.
“We are observing infections in areas where we do not automatically identify the source,” Lockwood noted, adding, “It’s a game of large numbers.”
Another mutation?
Until recently, virologists believed that multiple mutations were necessary for H5N1 to transition easily among humans.
However, a study published in Science magazine this month revealed that a cattle-circulating strain of the virus could bind to human receptors following a single mutation (Note: The study focuses solely on viral proteins, not the entire infectious virus).
“We are not implying that a pandemic is more imminent due to this finding. We simply want to highlight that the risk has elevated as a result,” explained Jim Paulson, co-author of the study and the director of molecular medicine at Scripps Research.
Separately, scientists have detected concerning elements in another virus variant found in a Canadian teen who fell severely ill in recent months. Virus samples indicated mutations that could enhance human-to-human transmissibility.
A CDC spokesperson stated that these mutations were unlikely present in the virus when the boy was infected.
“These mixed changes in the virus probably occurred following prolonged infection in the patient,” the spokesperson explained.
The strain of the virus in the first severe bird flu case in the U.S., announced on Wednesday, matched the one that infected the Canadian teenager.
Dr. Demetre Daskalakis, head of the National Center for Immunization and Respiratory Diseases, revealed that the CDC is analyzing patient samples to identify potential concerning variants.
Meanwhile, Hensley expressed concerns that the flu season could expedite virus evolution. If an individual is co-infected with seasonal influenza and avian influenza, genetic code segments can be exchanged between the two.
“Mutations are unnecessary; it’s simply a genetic code exchange,” Hensley asserted, emphasizing the importance of farmworkers receiving flu shots to reduce such opportunities.
Upcoming trials and vaccines
Experts highlighted various measures that can be taken to track bird flu spread more effectively and prepare for a possible pandemic, some of which are already in progress.
The USDA extended mass milk testing to a total of 13 states on Tuesday, accounting for approximately 50% of the national supply.
Nuzzo emphasized that efforts need to be intensified swiftly.
“We have delayed comprehensive bulk milk testing for too long, as it is a common method for detecting outbreaks on farms,” she stated.
Simultaneously, Andrew Trister, Verily’s chief medical and scientific officer, mentioned that the company is enhancing wastewater analysis to identify concerning mutations.
USDA additionally approved field trials to administer H5N1 vaccine to cattle. Hensley’s lab conducted tests on a new mRNA vaccine in calves.
The worsening effects of food supply on the climate
Raising cattle produces huge amounts of greenhouse gases
Alan Hopps/Getty Images
As the world's population grows, the only way to reduce agriculture's huge greenhouse gas emissions is to make food production more efficient. Unfortunately, efficiency gains have stagnated since 2010, and as food demand continues to grow, agricultural emissions and deforestation are likely to skyrocket.
Lin Ma Ma and his colleagues at the Chinese Academy of Sciences in Shijiazhuang came to their conclusion after analysing existing data to estimate greenhouse gas emissions per unit of protein produced between 1961 and 2019. They chose protein instead of calories because it's a better indicator of food quality, Ma says.
Between 1961 and around 2010, emissions per unit of protein fell by two-thirds, the team says. But since then, there has been no further improvement and there are even signs of an increase. Agriculture is responsible for about a third of all greenhouse gas emissions, and food demand is projected to increase by up to 50% by 2050. If agriculture's climate efficiency does not improve further, emissions from agriculture will also increase by 50%, the researchers warn.
Moreover, without improvements in agricultural efficiency, the only way to increase production is to clear more land for farming, which will lead to further deforestation and biodiversity loss, they say.
“That's very bad news. We need to drastically reduce emissions, not increase them.” Richard Waite He is a researcher at the World Resources Institute in Washington, D.C., but was not involved in the study.
“The continued and accelerating expansion of agricultural land since the turn of the century is of great concern as there is no path forward to limit warming to 1.5°C. [of global warming] “It's important to end deforestation as quickly as possible,” he says.
There are many reasons why climate emissions per unit of protein produced are no longer decreasing, Dan Leto For one thing, people around the world are eating more meat, which produces far more greenhouse gas emissions than plant-based foods, said Breakthrough Institute researcher David Schneider, who was not on the team.
The fact that large amounts of agricultural crops are now being converted to fuel rather than food could also be a factor, he says. “The rise in crop-based biofuels likely explains some of the slowdown in decarbonization we find in the paper,” as biofuel crops grown for energy are chosen for their calorie content rather than their protein content, reducing the efficiency that Ma's team measures.
Another potential factor is the increase in extreme weather events that are affecting crop yields and food prices around the world, which the study did not take into account, Ma said. “But we suspect the impact of extreme weather on crop yields was relatively small before 2019.”
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Source: www.newscientist.com
The impact of climate change on food costs: A prediction of rising prices and worsening conditions
Food prices are on the rise
AFP (via Getty Images)
Because of global warming, you are already paying more and more for groceries. And rising temperatures will cause food prices to rise significantly over the next decade.
By 2035, rising temperatures alone are expected to increase global food prices by 0.9 to 3.2 percent each year, according to a study conducted in collaboration with the European Central Bank. This would increase the overall inflation rate by 0.3 to 1.2 percentage points.
“We are often shocked and surprised by the magnitude of these effects,” he says. Maximilian Kotz He mentioned discussions he had with economists during his research at Germany's Potsdam Institute for Climate Impact Research.
Abnormal weather due to global warming Increasingly impacting food production around the world And if farmers don't adapt, the losses will become even more severe as the world continues to warm.
To find out how this is affecting food prices, Kotz and his colleagues looked at monthly price data for a variety of goods and services for 121 countries from 1996 to 2021 and the exposure to which those countries were exposed. The weather conditions were compared.
Researchers looked at the correlation between food prices and factors such as average monthly temperatures, temperature fluctuations, droughts and extreme rainfall. They found a strong association between average temperature and food prices a month or so later.
Areas north of 40 degrees latitude, such as New York City, Madrid, and Beijing, experienced warmer-than-average winter temperatures, leading to lower food prices. But not just in the summer, temperatures in other parts of the world have always been above average, causing food prices to rise.
Moreover, the impact on prices is long-lasting. “If prices go up based on one of these shocks, they stay high for at least the rest of the period,” Kotz says.
The study didn't look at why prices have increased, but one possible explanation is that extreme heat is reducing yields, he said. “The vines may be dry when the crop should be harvested.”
Kotz said factors such as extreme rainfall had a smaller impact on food prices than average temperatures. This may be because flooding tends to be localized, whereas above-average temperatures can be very widespread.
Other studies have reached similar conclusions, Kotz said. But his team went a step further and investigated how food prices would change based on increases in average temperatures in climate model projections. Under the team's worst-case emissions scenario, global food inflation due to climate change will exceed 4% per year by 2060. However, the team believes the 2035 prediction is more reliable, as many other factors could have changed by then.
“There are a lot of things that could happen that will change the way the economy responds to climate change,” Kotz said. For example, inflationary pressures would be reduced if farmers adapted their practices to better cope with rising temperatures. But so far, he says, there is no sign that farmers are adapting.
“I think these are realistic predictions. They are based on solid empirical evidence.” Matin Kaim At the University of Bonn, Germany. “We need to recognize the fact that climate change poses new and major challenges to food and nutrition security.”
according to Food Price Index of the Food and Agriculture Organization of the United Nations, The cost of food fell in real terms between 1960 and 2000, but has risen since then. Russia’s invasion of Ukraine in 2022 caused a massive surge – factors that influence this Protests are occurring in many countries. The index price has since fallen, but remains higher than before the invasion.
Like the US Federal Reserve and the Bank of England, the European Central Bank aims to: keep inflation around 2%. Rising food inflation will make achieving this goal even more difficult, Kotz said.
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Source: www.newscientist.com
Scientists Find Worsening Ice Melt in Greenland as Research Advances
According to a new study, Greenland’s ice sheet has lost approximately 1,965 square miles to glacier retreat since 1985, which is about the same area as the state of Delaware. The study utilized satellite images to track the retreat and discovered that iceberg collapse is accelerating in Greenland, with previous analyses potentially underestimating its impact. The authors of the study noted that the current estimates of ice sheet mass balance may underestimate recent mass loss from Greenland by up to 20%. In recent decades, nearly all of Greenland’s glaciers have thinned or retreated.
The study, published in the journal Nature, is another indication that Greenland’s ice is melting at a rapid rate. There is growing concern among scientists that global warming could trigger a major ice sheet tipping point. If Greenland’s ice completely melts, sea levels could rise by almost 7 feet and change ocean circulation patterns. Additionally, the study suggests that the United Nations Intergovernmental Panel on Climate Change may be underestimating how much ice is being lost in Greenland.
Several studies published last year highlighted Greenland’s rapid changes, including one that found the rate of glacier retreat in the 21st century to be twice as fast as the 20th century. Another study showed that floating ice shelves in northern Greenland have lost over 35% of their total volume and are weakening, which could threaten ice sheet stability.
In November, a report by 60 leading snow and ice scientists raised concerns about the fate of the world’s ice sheets, warning that if global average temperatures rise to about 2 degrees Celsius above pre-industrial baselines, the planet could see sea level rise of more than 40 feet in the coming centuries. The report also indicates that by 2 degrees Celsius, most of Greenland, most of West Antarctica, and vulnerable parts of East Antarctica will have a very long-term chance of warming, leading to relentless sea level rise and decline.
Source: www.nbcnews.com
