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Sven Torfin / WHO 2016

Good News: Low-Cost Mosquito Nets Continue to Prevent Malaria

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Sven Torfin / WHO 2016

Even in the technology-intensive world of medicine, there’s a lot to be said for simplicity. A new study [PDF] from the World Health Organization (WHO), which monitored 340 locations in five countries for five years, finds that bed nets treated with pesticide continue to stop malaria transmission, even as mosquitoes develop pesticide resistance. The report was presented at the annual meeting of the American Society of Tropical Medicine & Hygiene (ASTMH).

Mosquito nets have literally been around for ages; the Greek historian Herodotus noted their use in Egypt as early as the 5th century BCE. For all that time, they were pretty effective—certainly effective enough that people kept using them—but that efficacy got a boost in the mid-20th century when we started spraying them with pesticide. The year 2000 saw the introduction of the long-lasting insecticidal net (LLIN), an inexpensive bed net made with insecticide-treated fabric that drove down the number of malaria cases even further.

But heavy insecticide use has its costs. Pesticides are similar to antibiotics, in that they can’t kill every single one of the species they’re meant to destroy. The survivors reproduce, creating new generations that are able to resist the treatment. And the more we use, the faster they can adapt. We’re now facing a crisis of antibiotic resistance, and pesticide resistance is not far behind. Mosquitoes in 60 countries have already developed a resistance to the pesticides used in LLINs.

Sven Torfin / WHO 2016

 
Consequently, researchers at the WHO’s Global Malaria Programme were concerned that the rise of pesticide-resistant mosquitoes would create a decrease in LLIN effectiveness. They spent five years surveying LLIN use and pesticide resistance in 340 sites in malaria-heavy Benin, Cameroon, India, Kenya, and Sudan.

The results were surprisingly positive. People who used LLINs around their beds at night were significantly less likely than others to become infected. From 2000 to 2015, the WHO estimates, interventions like LLINs prevented around 663 million new malaria infections in sub-Saharan Africa. And of those potential cases, 69 percent were prevented by LLINs.

Co-author Tessa Knox of the WHO notes that the potency of LLINs comes not from the pesticide or the net alone, but from their combined power. “A resistant mosquito may not die immediately after landing on a net, but it could continue to absorb insecticide as it seeks a way to get through and bite a person beneath the net,” she said in a statement. “This may eventually kill the mosquito and stop onward transmission of malaria parasites.”

Encouraging though these findings may be, experts caution that there’s still a lot more work to do as pesticide resistance continues to spread.

Stephen Higgs is president of the ASTMH. “This study provides encouraging news that we have not yet run out of time in battling insecticide resistance,” he said in the statement. “However, we must take advantage of the time we now have to invest in research and generate new tools that will allow us to finally defeat this complex and challenging disease.”

A handful of those new tools are already in the works. Some researchers are exploring chicken feathers as a natural mosquito repellent, while others are developing high-tech pills that could deliver a week’s worth of malaria medication with one swallow.

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Medicine
Bill Gates is Spending $100 Million to Find a Cure for Alzheimer's
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Jamie McCarthy/Getty Images for Bill & Melinda Gates Foundation

Not everyone who's blessed with a long life will remember it. Individuals who live into their mid-80s have a nearly 50 percent chance of developing Alzheimer's, and scientists still haven't discovered any groundbreaking treatments for the neurodegenerative disease [PDF]. To pave the way for a cure, Microsoft co-founder and philanthropist Bill Gates has announced that he's donating $100 million to dementia research, according to Newsweek.

On his blog, Gates explained that Alzheimer's disease places a financial burden on both families and healthcare systems alike. "This is something that governments all over the world need to be thinking about," he wrote, "including in low- and middle-income countries where life expectancies are catching up to the global average and the number of people with dementia is on the rise."

Gates's interest in Alzheimer's is both pragmatic and personal. "This is something I know a lot about, because men in my family have suffered from Alzheimer’s," he said. "I know how awful it is to watch people you love struggle as the disease robs them of their mental capacity, and there is nothing you can do about it. It feels a lot like you're experiencing a gradual death of the person that you knew."

Experts still haven't figured out quite what causes Alzheimer's, how it progresses, and why certain people are more prone to it than others. Gates believes that important breakthroughs will occur if scientists can understand the condition's etiology (or cause), create better drugs, develop techniques for early detection and diagnosis, and make it easier for patients to enroll in clinical trials, he said.

Gates plans to donate $50 million to the Dementia Discovery Fund, a venture capital fund that supports Alzheimer's research and treatment developments. The rest will go to research startups, Reuters reports.

[h/t Newsweek]

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A New Analysis of Chopin's Heart Reveals the Cause of His Death

For years, experts and music lovers alike have speculated over what caused celebrated composer Frederic Chopin to die at the tragically young age of 39. Following a recent examination of his heart, Polish scientists have concluded that Chopin succumbed to tuberculosis, just as his death certificate states, according to The New York Times.

When Chopin died in 1849, his body was buried in Paris, where he had lived, while his heart was transported to his home city of Warsaw, Poland. Chopin—who appeared to have been ill with tuberculosis (TB)—was terrified of the prospect of being buried alive, and nostalgic for his national roots. He asked for his heart to be cut out, and his sister later smuggled it past foreign guards and into what is now Poland.

Preserved in alcohol—likely cognac—and stored in a crystal jar, Chopin's heart was laid to rest inside Holy Cross Church in Warsaw. (It was removed by the Germans in 1944 during the Warsaw Uprising, and later returned.) But rumors began to swirl, as the same doctor tasked with removing the heart had also conducted an autopsy on the composer's body, according to the BBC.

The physician's original notes have been lost, but it's said he concluded that Chopin had died not from TB but from "a disease not previously encountered." This triggered some scholars to theorize that Chopin had died from cystic fibrosis, or even a form of emphysema, as the sickly musician suffered from chronic respiratory issues. Another suspected condition was mitral stenosis, or a narrowing of the heart valves.

Adhering to the wishes of a living relative, the Polish church and government have refused to let scientists conduct genetic tests on Chopin's heart. But over the years, teams have periodically checked up on the organ to ensure it remains in good condition, including once in 1945.

In 2014, a group of Chopin enthusiasts—including Polish scientists, religious officials, and members of the Chopin Institute, which researches and promotes Chopin's legacy—were given the go-ahead to hold a clandestine evening meeting at Holy Cross Church. There, they removed Chopin's heart from its perch inside a stone pillar to inspect it for the first time in nearly 70 years.

Fearing the jar's alcohol would evaporate, the group added hot wax to its seal and took more than 1000 photos of its contents. Pictures of the surreptitious evening procedure weren't publicly released, but were shown to the AP, which described Chopin's preserved heart as "an enlarged white lump."

It's unclear what prompted a follow-up investigation on Chopin's heart, or who allowed it, but an early version of an article in the American Journal of Medicine states that experts—who did not open the jar—have newly observed that the famed organ is "massively enlarged and floppy," with lesions and a white, frosted appearance. These observations have prompted them to diagnose the musician's cause of death as pericarditis, which is an inflammation of tissue around the heart. This likely stemmed from his tuberculosis, they said.

Some scientists might still clamor at the prospect of testing tissue samples of Chopin's heart. But Michael Witt of the Polish Academy of Sciences—who was involved in this latest examination—told The Guardian that it was unnecessary to disturb what many consider to be a symbol of national pride.

"Some people still want to open it in order to take tissue samples to do DNA tests to support their ideas that Chopin had some kind of genetic condition," Witt said. "That would be absolutely wrong. It could destroy the heart, and in any case, I am quite sure we now know what killed Chopin."

[h/t The New York Times]

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