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Scientists seek super-shot for the flu 100 years after the pandemic



The descriptions are disturbing.

Some victims felt good in the morning and were dead at night. The faces turned blue as the patients spat blood. The stacked bodies outnumbered the coffins.

A century after one of the most catastrophic epidemic outbreaks in history, scientists are reconsidering how to protect themselves from another super flu like the 1918 flu that killed tens of millions while sweeping the globe.

how to predict which type of flu virus changes shape could trigger another pandemic or, given modern medical tools, how bad it could be.

But researchers hope they will finally come closer to stronger flu vaccines, ways to boost a lot – it needs protection against the common winter flu and protection against future pandemics at the same time.

"We have to do better and, better, we refer to a universal flu vaccine, a vaccine that will protect against essentially all, or most, strains of the flu," said Dr. Anthony Fauci of the National Institutes of Health.

Laboratories across the country are looking for a super vaccine that can eliminate annual fall vaccination in favor of one every five years or 10 years, or maybe, eventually, a childhood immunization that could last a lifetime.

Fauci is designing a universal flu vaccine as one of the top priorities of the NIH National Institute of Allergy and Infectious Diseases. Last summer, he gathered more than 150 leading researchers to chart a path. Some attempts are entering the first stage of human security testing.

Still, it's a difficult task. Despite 100 years of science, the influenza virus often exceeds our best defenses because it constantly mutates.

Among the new strategies: researchers are dissecting the mantle that disguises the flu when it escapes the immune system and find some rare objectives that remains the same tension in tension, from year to year.

"We have made some serious inroads into understanding how we can best protect ourselves, now we have to bring it to fruition," said the famous biologist Ian Wilson. of the Scripps Research Institute in La Jolla, California.

The somber centennial highlights the need.

Back then, there was no vaccine against the flu, it would not come in decades. Today vaccination is the best protection, and Fauci never skips his. But in the best of cases, the seasonal vaccine is 60 percent effective. Protection fell to 19 percent a few years ago when the vaccine did not match an evolving virus.

If a flu strain never seen before erupts, it takes months to make a new vaccine. The doses came too late for the last, fortunately mild, pandemic in 2009.

Without a better option, Fauci said the nation is "chasing" strains of animal flu that could become the next human threat. Today's main concern is a deadly bird flu that jumped from poultry to more than 1,500 people in China since 2013. Last year it was mutated, which means that millions of doses of justified vaccines in a US reserve no longer match .

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Dr. Jeffery Taubenberger of the NIH calls the 1918 flu the mother of all pandemics.

He should know.

While working as a pathologist for the military, he led the team that identified and reconstructed the extinct 1918 virus, using traces unearthed in autopsy samples of World War I soldiers and a victim buried in the permafrost of Alaska.

That misnamed Spanish flu "made the whole world a zone of death," wrote John M. Barry in "The Great Influenza": The History of the Deadliest Pandemic in History "

Historians believe that It began in Kansas in early 1918. In the winter of 1919, the virus had infected a third of the world's population and had killed at least 50 million people, including 675,000 Americans .. In comparison, the AIDS virus has claimed 35 million lives in four decades.

Since 1957, 1968 and 2009, three other flu pandemics have exploded, which have spread widely but are by no means so lethal.Tubenberger's research shows the family tree, each subsequent pandemic is the result of influenza viruses carried by birds or pigs mixed with 1918 flu genes.

"This 100-year timeline of information on how the virus adapted to us and how it did not We adapt to the new virus, it teaches us that we can not continue to design vaccines based on the past, "said Dr. Barney Graham, deputy director of the NIH Vaccine Research Center.

The new vaccine search begins with two proteins, hemagglutinin and neuraminidase, that cover the surface of the flu. The "H" allows the flu to adhere to respiratory cells and infect them. Subsequently, the "N" helps spread the virus.

They also form the names of influenza A viruses, the most dangerous flu family. With 18 varieties of hemagglutinin and 11 types of neuraminidase, most carried by birds, there are many possible combinations. That virulent virus of 1918 was the subtype H1N1; milder H1N1 strains still circulate. This winter H3N2, a descendant of the 1968 pandemic, is causing most of the misery.

Think of hemagglutinin as a miniature broccoli stalk. Its head similar to a flower attracts the immune system, which produces antibodies blocking infections if the upper part is similar to a previous infection or vaccination that year.

But that head is also where the mutations accumulate.

A turning point towards better vaccines was a 2009 discovery that, sometimes, people produce a small amount of antibodies that instead target spots on the stem of hemagglutinin that do not mutate. Even better, "these antibodies were much broader than anything we've seen," capable of blocking multiple influenza subtypes, said Wilson of Scripps.

Scientists are trying different tricks to stimulate the production of these antibodies.

lab at the NIH Vaccine Research Center, "we think that taking the trouble will solve the problem," Graham said. Your team makes the stems vaccine and attaches them to ball-shaped nanoparticles easily detected by the immune system.

In New York, the pioneer of influenza microbiology Peter Palese at the Icahn School of Medicine in Mount Sinai uses "chimeric" viruses: the head of hemagglutinin comes from bird flu, the stem of the common viruses of the human flu, to redirect the immune system.

"We have made the head so that the immune system does not really recognize it," Palese explained. GlaxoSmithKline and the Gates Foundation are funding initial safety tests.

In addition to working with Janssen Pharmaceuticals on a stem vaccine, Wilson's team is also exploring how to convert anti-influenza antibodies into an oral medication. "Let's say a pandemic arrived and you did not have time to make the vaccine, if you could, you would want something to block the infection," he said.

Taubenberger of NIH takes a completely different approach. He is preparing a cocktail of vaccines that combines particles of four different hemagglutinins that in turn trigger protection against other related strains.

However, the persistent mysteries hinder the investigation.

Scientists now believe that people respond differently to vaccination in their flu history. "We may better recognize the first flu we have seen," said NIH immunologist Adrian McDermott.

The idea is that your immune system is marked with that first strain and that it does not respond as well to one vaccine against another.

"The vision of the field is that, ultimately, if you get the really good flu vaccine, it will work better when you give it to a child," Fauci said.

Even so, nobody knows what the definitive origin of that terrifying 1918 Flu is. But the key to its lethality was the bird-like hemagglutinin.

Chinese H7N9 bird flu "I'm very worried," said Taubenberger. "For a virus like the flu that is a master at adapting and mutating and evolving to face new circumstances, it is vital to understand how these processes occur in nature … How does an avian virus adapt to a mammal?"

As long as scientists look for those answers, "it's foolish to predict" what could bring an upcoming pandemic, said Fauci. "We just need to be prepared."


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