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A killer fungus has spread across Africa, killing even more amphibians.



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The killer fungus that caused the worst wildlife disease in history, wiped out or brought hundreds of amphibian species to the brink of extinction, has become more common in Africa than anyone thought and is likely causing unnoticed outbreaks.

A fungal infection called chytridiomycosis, first described in the late 1990s, swept through this rich continent in little more than two decades, perhaps driven by air travel and the animal and food trade. according to new research in Frontiers in Conservation Science. Ominous news from the study suggests that one line of fungus thought to be benign is more common and possibly more dangerous than previously thought.

“There is no other pathogen that causes a disease even close to this,” said study co-author Vance T. Vredenburg, chair of the Department of Biology at San Francisco State University. He holds a jar full of dead frogs to remind himself of what it was like to witness firsthand how the disease decimated frog populations in the Sierra Nevada mountain range between 2004 and 2008.

While most pathogens infect or kill a limited number of species, this the fungus “is a universal remedy for all amphibians, and it does very well,” Vredenburg said. The fungus is considered an important reason why 41 percent of amphibians worldwide are endangered.

“We’re incredibly lucky that it doesn’t affect mammals,” Vredenburg said.

In terms of scale, The closest human disease to chytridiomycosis is the Black Death, Vredenburg said, referring to the mid-14th-century bubonic plague that killed a third of Europe’s population in five years.

The destruction of amphibian species is damaging ecosystems around the world. Frogs and salamanders feed on disease-causing mosquitoes and other insects to control their populations. They also provide food for larger frogs, snakes, and some bird species.

The new study’s findings are important because “Africa has been a part of the world where we’ve always had a big question mark” about the fungus, said Jamie Voyles, an assistant professor of biology at the University of Nevada Reno who has written about chytridiomycosis but was not involved in the study.

The continent is home to more than 1,200 of the world’s 8,592 known amphibian species, making it a key benchmark for measuring the impact of chytrid mycosis. Amphibians, a class of animals that can live both on land and in water, consist of three groups: frogs, salamanders, and worm-like animals called caecilians.

Vredenburg said the researchers find cause for hope in the fact that “there are quite a few [amphibian] species that get infected and nothing happens.” What protects resistant animals, however, remains unclear.

Spores of an aquatic fungus known as volume, short for scientific name Batrachochytrium dendrobatidis, look into the skin of frogs and salamanders. Within 24 hours, the fungus can produce thousands more spores, which are released back into the water where they swim using a filamentous structure called a flagellum. New spores can infect both the same frog and others.

The fungus kills by causing the amphibian’s skin to grow up to 40 times its normal thickness, making it difficult for the animals to breathe and causing them to become dehydrated. In the end, many have conditions that cause cardiac arrest.

For their study, Vredenburg and his colleagues cast a wide net looking for signs of disease in Africa as early as 1852. They examined 16,900 amphibian specimens, of which almost 3,000 were taken from museums and 1,651 from wild animals in Burundi, Equatorial Guinea, and Cameroon. and the Democratic Republic of the Congo. They also included amphibians reported in previous journal studies. The earliest known example of the fungus worldwide dates back to 1933 and was discovered in Cameroon.

Vredenburg and colleagues found that, starting shortly before the 1960s, the fungus was present in less than 5 percent of the samples they studied during each decade. Then its presence soared to 17.2 percent in 2000. The study showed that the fungus is spreading particularly quickly in Cameroon and Kenya.

In Cameroon they found that a line of mushrooms known as Bd-CAPE spread and turned out to be more dangerous than previously thought.

“I love seeing studies like this that combine a lot of different methods to tell a story,” said Andrea J. Adams, research fellow at the Institute for Geosciences at the University of California, Santa Barbara.

But the work leaves open an important question: Why has the fungus spread so rapidly since 2000?

In his own study of the disease in Southern California in the 1950s, 60s, and 70s, Adams concluded that the appearance of the fungus coincided with a post-war land boom in the region and the construction of new roads that would allow the pathogen to reach frog populations in the mountains.

In Africa, Vredenburg and his colleagues found one country, Equatorial Guinea, where there was a significant decline in the prevalence of the fungus. They don’t know the reason.

In some cases, its spread can be traced through air travel or shipping, which increased the number of connections between different countries and between islands. In the Caribbean, frogs carrying bananas carried the fungus from one island to another, Vredenburg said.

Exotic pet trade linked to invasive fungus killing frogs worldwide

“As we expand connectivity,” he added, “we will disrupt millions of years of evolution between pathogens and hosts.”

The huge decline in amphibian populations could lead to a change in the fundamental human experience, Voyles says. “Everyone can remember how they caught frogs or tadpoles as a child. The joy of discovery is incredible.”

Adams said the threat is important because “biodiversity is our knowledge. We need to keep everything around for as long as possible.” Some amphibians can be used medicinally, while others may have benefits that people were not even aware of.

For Vredenburg distribution volume the fungus is a sobering reminder that he did not initially realize how much of a threat it posed to the frogs he studied in the Sierra Nevada.

“These frog populations are so resilient. Come on, they’ve been here in the mountains for millions of years,” he recalls thinking at the time. “Of course, the fungus came and destroyed them. I have seen tens of thousands of dead frogs.”

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Extreme weather meets reality of poverty to create tragedy in Mississippi



The tornado that hit Rolling Fork was also an intense, fast-moving storm that struck under cover of night when visibility is low and people are likely to be asleep and caught off guard.

“All of these different factors combined to create the perfect storm, and unfortunately we have seen the results of that,” Strader said.

Matt Laubhan, Mississippi meteorologist for NBC affiliate WTVA, said there are many tornadoes in Mississippi, including a devastating EF-5 from almost 12 years ago. He noted that some areas affected by these hurricanes received funding for temporary shelters, but there are no such facilities in Rolling Fork.

“When you talk about Rolling Fork, it’s a much more economically depressed area,” Laubhan. said Andrea Mitchell of NBC News. “And this is a place where there were no such public shelters.”

Robert Bradford, director of the Adams County, Mississippi Emergency Management Agency who helps coordinate response efforts, said Rolling Fork does not have a public safe room.

As the storm developed Friday, William Gallus, professor of meteorology at Iowa State University, said his worst fears had come true. In addition to forming at night, the tornado had a rare long trail that cut 59 miles across the Mississippi. Less than 1% of tornadoes remain on the ground for more than 50 miles.

“If there is a tornado outbreak in the southeast at night, you know there will be people badly injured or killed, and the best thing you can do is hope the tornadoes go through the needle and let the real small towns through,” he said. .

In the southeast, mobile homes are particularly vulnerable to tornadoes, which are classified according to what is known as the Enhanced Fujita Scale (EF). The weakest tornadoes, or EF-0 and EF-1, have winds up to 110 mph and typically do relatively little damage. The most powerful tornadoes, or EF-5s, have winds in excess of 200 miles per hour and usually cause catastrophic damage.

Preliminary research indicates that the tornado that hit Rolling Fork had winds of 170 mph, and the National Weather Service in Jackson, Mississippi rated the storm as EF-4.

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Cases of drug-resistant fungi have tripled during the COVID pandemic



As the US healthcare system has taken blow after blow from the COVID pandemic, diseases of all kinds, from HIV to congenital syphilisswept across the country. Last week, a national survey by the Centers for Disease Control and Prevention found that outbreaks of new drug-resistant fungi were also growing at an “alarming” rate in hospitals from 2019 to 2020.

Annual cases of opportunistic intractable yeast candida golden nearly tripled from 476 in 2019 to 1,471 in 2021.according to a recent CDC report that was published in Annals of Internal Medicine. Infectious disease experts say the COVID pandemic has likely exacerbated an already growing outbreak of the fungus, diverting attention and resources needed to slow down. C. auris transmission of infection. In some cases, the practices needed to protect healthcare workers and patients from COVID, such as reusing high-demand masks, may have increased the risk of spreading the fungus.

“Problems with [C. auris] Infection control existed before the advent of COVID-19,” says Megan Lyman, an epidemiologist specializing in mycology at the CDC and lead author of the study. “But I think some of the changes that were made to this strange world had consequences that we didn’t know about at the time.”

ace C. auris becomes more common, it will make recovery from catastrophic injury or illness more dangerous for vulnerable patients, such as those who are immunocompromised and with pre-existing medical conditions. “Almost everyone will be hospitalized or have a loved one hospitalized at some point in their lives,” says Lucy Witt, an infectious disease physician at Emory University who was not involved in the recent study. “This is everyone’s problem.”

C. auris closely related to several common yeasts that live in the human digestive tract, such as fungal microorganisms albicans, which causes mild infections. But C. auris causes more anxiety than its counterparts. Yeast lives on the skin, not in the gut, which allows it to spread easily from person to person. IN 2021 survey of one skilled nursing facility Conducted by the CDC and the Chicago Department of Public Health (CDPH), swabs found fungus on window sills, bed rails and doorknobs both inside and outside of patients’ rooms. It sticks to surfaces for weeks and is immune to some common disinfectants.

For most healthy people C. auris does not spread throughout the body from the skin. It’s just becomes a deadly problem for people with weakened immune systems. In these cases, “patients tend to be really sick at baseline,” Lyman says.

Infection in healthcare settings is the cause of most, if not all, according to a new CDC report. C. auris cases in the United States, with most diagnosed in long-term care hospitals and skilled care facilities. Patients treated in these facilities typically have an intravenous catheter, catheter, or other invasive medical device that creates a passage between the skin and internal organs. When ingested, yeast can cause opportunistic diseases, such as those recovering from organ transplants, chemotherapy, or other medical procedures that destroy the body’s innate immune defenses. Sepsis and fever are common symptoms, and studies have shown a fatality rate of 30 to 60 percent. WITH C. auris was first identified in the United States in 2016, reported nosocomial infections nearly doubled.

And ‘to add harm to harm, [C. auris] able to resist many antifungal drugs,” says Ilan Schwartz, a fungal infection specialist at Duke University School of Medicine.

For the treatment of patients with C. auris against about half a dozen classes of antibiotics used to treat bacterial infections. Resistance to any one drug severely limits the ability of clinicians to suppress infection. By 2020, nine patients in the US had infections resistant to echinocandins, the first-choice antifungal drugs doctors use to treat cancer, according to a new study. C. auris. By 2021, the CDC identified 27 cases of echinocandin resistance, seven of which were resistant to all antifungals.

Pharmaceutical companies are currently testing several new antifungal drugs, making it “a very, very exciting time to study fungal infections,” Schwartz says. An oral drug similar to cutting-edge echinocandins and already approved for treating vaginal yeast infections is being tested for use against systemic infections. Candida .

But the best way to control the spread of drug-resistant organisms is to constantly clean up.

The Chicago health system has been at the forefront of the fight against C. auris infections since 2016, when his hospitals for the first time Outbreak in the US The city’s Department of Public Health began tracking agencies that reported the fungus. At one skilled nursing facility in 2018, 43 percent of residents tested had marks on their skin. In eight months of follow-up testing, that number rose to 71 percent. The rapid rise in cases forced city health officials to coordinate a response that included handwashing training and the use of fluorescent markers to assess how thoroughly rooms are being cleaned.

“A lot of what came out of it was a recognition that people do more than just clean a room; they really help with the care of residents,” says Stephanie Black, medical director of the CDPH infectious disease program. It was also important to convince administrators that “you need to spend your resources cleaning up the environment,” she says. Prior to the outbreak at this nursing facility, staff used the correct cleaning products, but they didn’t necessarily leave these materials on surfaces long enough for them to take effect. The improvement also came from simply clarifying cleaning responsibilities, such as “defining who cleans the IV stands, who cleans the IV machine,” Black says. In response to the outreach by the CDPH, the nursing facility added dozens of hand sanitizer dispensers and hired another full-time cleaner to focus on the fungus. The level of fungi at the facility stabilized during the study. (In a letter to Scientific AmericanThe CDPH has stated that it cannot disclose more recent site-specific prevalence data.)

Control measures have helped slow the outbreak, but “you see how it gets lost in all of the COVID-related issues,” Black says. She adds that many of the nurses CDPH trained have quit their jobs, “so there’s a lot of retraining.” Nursing staff, hard hit by the COVID pandemic, are essential in dealing with outbreaks. Across the country, nurses have quit or taken on traveling jobs, and a quarter of hospitals reported staff shortages in March 2022.

Although Witt says the new report does not provide “detailed details” of what exactly caused the rapid surge C. golden, researchers say the pandemic is likely exacerbating outbreaks. COVID caused an increase in many healthcare-associated infections. Organ damage by the disease-causing virus leaves people vulnerable to opportunistic infections, and steroids and antibiotics used to treat COVID complications can increase the risk fungal infection. Health care workers who resorted to reusing masks and gloves to slow the transmission of a respiratory disease may have created a vector for the organism to travel across surfaces. “Everyone was trying to do their best under dire circumstances,” Lyman says.

Even as the burden of COVID eases, understaffing and burnout are likely to be ongoing sources of risk. “But we don’t want people to be hopeless,” Lyman says. “Certainly there are means capable of controlling [C. auris] outbreaks.” The researchers, however, say that replicating this success will likely require significant investment in the health departments that coordinate the response, as well as in the medical workers on the ground.

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Inside Britain’s largest sewer under the River Thames in London



For decades, the sewers of Victorian London dumped raw sewage into the Thames after heavy rains.

But that may soon change thanks to a huge tunnel under the river.

Seven meters wide, 25 kilometers long and costing almost £5 billion, it is designed to carry wastewater to a wastewater treatment plant in east London.

Our environmental correspondent Jonah Fisher got the rare opportunity to cycle through the tunnel before it fills with sewage.

Director: Sofia Woodcock

filming and editingStory by: Kevin Church

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