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Researchers Explain Why Flu Shots Don’t and Can’t Work

Researchers Explain Why Flu Shots Don’t and Can’t Work 86

Flu vaccine season is already in full swing, with banners outside pharmacies urging: “Get Your Flu Shot Now.” What’s not advertised, however, is just how lackluster the vaccine is. The most commonly used flu shots protect no more than 60% of people who receive them; some years, effectiveness plunges to as low as 10%. Given that a bad flu season can kill 50,000 people in the United States alone, “10% to 60% protection is better than nothing,” says Michael Osterholm, an epidemiologist at the University of Minnesota in Minneapolis. “But it’s a terribly inadequate vaccine for a serious public health threat.” Now, researchers are striving to understand why it fails so often—and how to make a markedly better one.

They’re questioning what was once received wisdom: that the vaccine fails when manufacturers, working months ahead of flu season, incorrectly guess which strains will end up spreading. And they’re learning instead that the vaccine may falter even when the right strains were used to make it, perhaps because of how it is produced or quirks of individual immune systems.

“It’s much more complicated than we thought,” Osterholm says. “I know less about influenza today than I did 10 years ago.”

The influenza vaccine teaches the body to produce antibodies against the head of the virus’s surface protein, hemagglutinin (HA). Those antibodies ideally prevent HA from attaching to cellular receptors, thwarting infection. But HA’s head is highly mutable, which is why vaccinemakers must come up with a new formula every year.

For many decades, researchers believed the flu vaccine offered solid protection if it was a good match to the circulating strains; studies from the 1940s through the 1960s routinely showed an efficacy of 70% to 90%. But those studies relied on a misleading methodology. Without a simple way to detect the virus in the blood, researchers measured antibody levels, looking for a spike that occurs after infection.

Then in the 1990s, sensitive polymerase chain reaction tests enabled researchers to actually measure viral levels, and they told a different story. It turned out that some people who did not have the big antibody spike after exposure—and were therefore counted as a vaccine success—actually did show a jump in viral levels, signalling infection. Earlier assessments had exaggerated vaccine efficacy. What’s more, efficacy was sometimes low even when the vaccine and circulating strains appeared well matched. Something else was afoot.

Loss of confidence

For decades, tests suggested the flu vaccine worked extremely well, but in the past 15 years a better test revealed many infections in vaccinated people who would previously have been deemed protected.

Credits: (graphic) g. Grullón/Science; (data) F. M. Davenport et al. Med j aust. 1973; suppl 33-38; centers for disease control & prevention

Credits: (graphic) g. Grullón/Science; (data) F. M. Davenport et al. Med j aust. 1973; suppl 33-38; centers for disease control & prevention

The circulating strains continue to mutate after the vaccine is made, and the resulting “escape mutants” are often blamed for vaccine failure. But Arnold Monto, an epidemiologist at the University of Michigan School of Public Health in Ann Arbor, is skeptical that escape mutants play a major role. In a preprint published 15 August on bioRxiv, his team reports sequencing influenza DNA from 249 viral specimens collected from people over five influenza seasons. They found loads of HA mutations, as expected, but most weakened the virus, making it “unfit,” meaning it could not transmit human to human. Viable escape mutants, Monto concludes, are too rare to explain the failures seen year after year.

Danuta Skowronski, an epidemiologist at the BC Centre for Disease Control in Vancouver, Canada, instead blames mutations in the vaccine strain itself. The most common influenza vaccine contains an “inactivated” virus, which manufacturers grow in chicken eggs. As Skowronski’s team first reported in 2014, the virus can mutate while it is growing in the eggs, resulting in a vaccine unable to block circulating strains.

“I think [these mutations] play an enormous role,” says viral immunologist Scott Hensley of the University of Pennsylvania. He has preliminary evidence that egg-adapted mutations were behind the weak protection seen with the vaccine used in the 2016–17 season, he says. He also points to a recent study by another group that compared an egg-grown vaccine with one that contained genetically engineered HA, which sidesteps the mutation issue. The engineered vaccine offered more solid protection. That suggests a way to improve current vaccines, Hensley says. “I’d be shocked in 15 years if any of our flu vaccines are grown in eggs.”

When flu virus is grown in eggs to make the vaccine, mutations can occur in key places (red) on the viral surface protein hemagglutinin, which undermine the shot's protective powers.

When flu virus is grown in eggs to make the vaccine, mutations can occur in key places (red) on the viral surface protein hemagglutinin, which undermine the shot’s protective powers.

Hensley notes another way to reduce the odds of failure: improving the techniques for choosing the vaccine strains. Vaccinemakers largely rely on an old technique that exposes ferrets—which differ from humans—to candidate vaccine strains and then assesses whether they can stop viral isolates from people naturally infected with the circulating strains. Genetic comparisons, he says, would yield a better match.

Understanding the immune responses that correlate with protection could also help refine vaccines. Immune responses to targets other than HA’s head, including HA’s stem and a second viral surface protein, neuraminidase, receive scant attention. Further complicating the picture is the immunologic legacy of multiple exposures to influenza each year—from the vaccine and from wild-type virus. “What is the effect of primary and subsequent exposure to the virus?” asks Adolfo García-Sastre, an influenza vaccine researcher at the Icahn School of Medicine at Mount Sinai in New York City. “It makes it very difficult to come up with hard data about what’s going on.”

Hensley’s group has shown that the immune system is also biased by a child’s first exposure to flu, which leaves a ghost that affects responses to subsequent vaccines. This may explain why middle-aged people in 2013–14 were unusually hard-hit by a viral mutant that did not infect most vaccinated people, his team has reported. The team’s studies showed that in this age group, the vaccine elicited antibodies to a similar—but not identical—HA they had seen as kids, and the resultant immune response missed the target. “These first exposures really shape how we respond our entire lives,” Hensley says. Immunologist Rafi Ahmed at Emory University in Atlanta last year reported that long-lived memory B cells to flu, which produce antibodies, can crowd out B cells that would otherwise respond to novel infections.

Other evidence suggests that repeated vaccinations can blunt the immune response to some HAs. “We don’t understand enough about the effects … to make any recommendations right now,” says Edward Belongia, an epidemiologist at the Marshfield Clinic Research Institute in Wisconsin, who led a recent meta-analysis. “The best strategy remains to get a vaccine every year.” This is especially true for the elderly or immune-compromised people: Even if a vaccine fails to prevent infection, they may suffer less severe disease if immunized.

The BC Centre’s Skowronski says many influenza researchers are hesitant to discuss problems with the vaccine “because they’re afraid of being tainted with the antivaccine brush.”

She says that’s a mistake. “This immunization program has been predicated on assumptions on top of assumptions. Unless we have these discussions, we’ll never have improved vaccine options. And I don’t think it’s antivaccine to want your vaccine program to be the best that it can be,” she adds.

Skowronski thinks the field must more aggressively pursue a universal influenza vaccine that would work against many strains and last for years. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, agrees. He wants to accelerate that work by creating a new consortium of top researchers, which he hopes next year’s budget can fund. “I’m going to make universal influenza vaccine my top priority over the next couple years,” Fauci says. “We’ve got to do better.”

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New Physics: Mysterious radiation pointed to the verge of discovering a “ghost” particle that makes up dark matter

New Physics: Mysterious radiation pointed to the verge of discovering a "ghost" particle that makes up dark matter 91
Photo: Daniel Molybdenum, NASA's Goddard Space Flight Center

Physicists at the Lawrence Berkeley National Laboratory in the United States have found that the mysterious high-energy radiation emitted from the vicinity of a group of neutron stars may indicate the existence of axions – not yet discovered particles within the framework of New Physics, the search for which has been going on since 1977. It is assumed that special types of axions form dark matter. This is reported in an article published in the journal Physical Review Letters. The research is summarized in a press release on Phys.org.

It is believed that axions can form in the core of neutron stars and transform into photons in the presence of a powerful magnetic field. To detect the electromagnetic radiation associated with axions, you need to find stars that do not emit radiation at different wavelengths that can mask the desired signal. 

These objects include the Magnificent Seven neutron stars that emit only X-ray and ultraviolet radiation. They are located at a distance of 200-500 parsecs from the Earth.

The researchers ruled out the scenario that the excess X-rays produced by the Magnificent Seven are actually emitted by other, more distant objects. These sources would be found in datasets from the XMM-Newton and Chandra X-ray space telescopes.

The extra X-rays likely originate from axions hitting an extremely strong electromagnetic field billions of times stronger than the magnetic fields that could be created on Earth, the scientists concluded. The axions themselves resemble neutrinos in their properties, since both have insignificant masses and rarely and weakly interact with matter.

The axion is currently viewed as the most promising candidate for dark matter particles, since another hypothetical candidate, the massive WIMP particle, has gone unnoticed in experiments aimed at detecting it. 

In addition, there may be a whole family of axion-like particles that form dark matter, as suggested by string theory. If axions are found, it will prove that there is a whole new area of ​​physics outside the Standard Model describing the properties of all known particles.

To find out, the next step will be to study white dwarfs, which are not expected to emit X-rays.

“If we see an abundance of X-rays there too, our arguments will be pretty compelling,” said lead author Benjamin Safdie.

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The goal of human civilization is to create AI and disappear?

The goal of human civilization is to create AI and disappear? 92

Various sources often talk about civilizations that lived long before us. They all developed, prospered for a while, and then disappeared in an incomprehensible way. 

What is the reason for their decline, we probably will not know. All we can do is admire the remains of stone buildings, over which time has almost no power.

While looking for an answer, we somehow accidentally stumbled upon an interesting saying about the life of Japanese samurai: “A samurai has no goal, but a path.” In the end, the “path of the samurai” ended in what is known – death. The path of any civilization ended in the same way.

If you look at the issue through the prism of a samurai saying, then there is no point in looking for why and how civilization ended its existence. Probably, the process itself and its result are important here. But to whom is it important and what result does it expect?

Mysterious director

Apparently, behind the curtains of this “ancient theater” there is a mysterious “director” who periodically makes necessary adjustments to the history of civilization.

To figure out what’s what, you need to look at current trends in science. Where does a person strive with such an irresistible desire to “play God.” This attracts him and at the same time frightens him, but in no way turns him away from the intended path. Most likely, artificial intelligence (AI) is the purpose of our civilization’s existence.

About 50 years ago it would have seemed nonsense, but to someone, perhaps even now. However, if you trace the last 100 years of the life of our civilization, you get the feeling that most of the discoveries were given to mankind at the same time. A powerful leap has taken place in a hundred years. Why did it happen?

At the beginning of the last century, scientists recognized the existence of fields that have memory and the ability to store and transmit information. It is very likely that such or a similar field can be around the Earth and, more interesting, possess intelligence. Isn’t this the same “Director” hiding behind the screen of the “ancient theater”?

If this is so, then at a certain moment the “Director” gives the selected scientist “access” to certain knowledge (perhaps even in a dream, like Mendeleev), and another scientific breakthrough occurs in the world. Step by step, discovery after discovery, humanity is steadily moving towards the creation of AI. The trend is already well visible.

The goal of human civilization is to create AI and disappear? 93

AI is probably the next “Babylon”, which will combine all the knowledge, culture and accumulated experience of civilization. In the future, the neural network will enter into a connection with the general information field and leave humanity without knowledge, technology, and even a spoken language. This will be the next decline of civilization. And the “Director” will receive another array of new data (experience) in order to start creating a new civilization.

If someone believes that past civilizations ended in large-scale conflicts, then most likely this is already the consequences of “turning off” AI.

Co-founder of Skype talked about the threat of AI to humanity

One of the creators of the Skype internet call service, Jaan Ta

The goal of human civilization is to create AI and disappear? 94
Photo: 
© still from the movie “Terminator 2: Judgment Day”

llinn, said that the development of artificial intelligence (AI) threatens humanity. According to him, humans face three key threats, but it is AI that should be feared most of all, the expert said. 

Tallinn explained that at the moment, no one can predict what development AI will achieve in the next decades. In addition, the fact that scientists are creating artificial intelligence that can form a new AI without human intervention is also a cause for concern.

In addition, as the co-founder of the popular video calling service noted, the development of synthetic biology also causes concern. According to him, this direction in science allows the creation of artificial DNA sequences and biological systems that may not exist in nature.

Tallinn also drew attention to the fact that he fears we are entering an era of “unknown unknowns”, things that people are not even able to imagine right now.

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Volkswagen robot will autonomously charge cars: a working prototype presented

Volkswagen robot will autonomously charge cars: a working prototype presented 95
Copyright: © VW

The renowned German car manufacturer announced a new development. This time, engineers have created a unique robot capable of autonomously charging electric vehicles. 

For more than a year, specialists have been developing this project, but only now the concern was ready to demonstrate the first working prototype. The robot is ready to charge electric vehicles and has shown the high efficiency of this process.

It is called the Mobile Charging Robot, and experts have already compared it to the R2-D2 droid from Star Wars, including squeaks and clangs. Indeed, there is a similarity. Before implementing this idea, the engineers decided that robots should be allowed to charge cars parked in large residential complexes.

This will save their owners from leaving in order to find a gas station. Another advantage is that large parking lots and garages do not have to contain several expensive charging points for electric cars. The car company said in a press release that the robot works exclusively autonomously.

It independently controls and interacts with the vehicle being charged. It opens the cover of the charging socket and independently connects the power plug, then disconnects it. The robot looks like a trailer, which is a mobile energy storage.

It is capable of charging multiple electric vehicles at the same time. Despite the fact that the manufacturer confidently praises its concept, experts saw inefficiency in the fact that first it is necessary to charge the robot’s battery, which is then used to recharge electric cars.

Volkswagen Group Components CEO Thomas Schmall noted that creating an efficient charging infrastructure for the cars of the future is an important step in the company’s development.

Its engineers focus on finding solutions to avoid costly do-it-yourself measures. The mobile robot is only part of the concept that will continue to be developed.

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