Over several years, they were able to piece together the whole genome of the influenza virus — and they used that to resurrect this extinct virus. So in the late s, most virologists were starting to brace for the next flu pandemic. Then in the H5N1 avian flu emerged. And while it was devastating to poultry, it was also able to infect and kill people. We had never seen a flu virus jump straight from birds to people before.
Could that have been how started? Could there be clues in the virus that would tell us what to look for in new strains of flu that would give us early warning of a new pandemic strain?
So the virus was resurrected to try and understand what made that pandemic worse than others in the hopes of helping us be better prepared for the next one. Koci: This work took about eight years and a team comprised of at least three different institutions. But the real answer is more complicated than that. The virus came from birds, but it spent time evolving to infect humans in some other animal. We learned that changes in the protein that the flu uses to get into our cells HA protein worked differently than most other influenza viruses, and if we moved just that gene into seasonal flu strains, they got more virulent.
However, if we replaced the virus HA gene with the HA from the seasonal flu and left all the other genes the same, was just as virulent no matter which HA gene it had. So the HA gene plays a role but all the other genes do, too. Stop waiting for nature to spit out a new strain and then rush to make a vaccine to it. We learned we really need a universal influenza vaccine, a vaccine that will provide protection to all strains of the flu no matter what nature decides to throw at us.
We also learned we need more weapons than just vaccines. We need more antivirals, designed to target all the different parts of viruses. And not just influenza virus but every virus we think might have pandemic potential. We have made progress on these lessons. Also, we have a few more antiviral drugs today than we did 20 years ago, but clearly not enough to be ready for the next pandemic, this pandemic. TA: Is there anything else in particular you think is worth noting to a general audience from the broader field of research into historical viruses?
Koci: Nature gave us fair warning something was coming. A lot of people have been ringing alarm bells for years, but pandemic preparedness is a tough sell. When it works, nothing happens and it looks like you wasted all that money.
H1N1 did take off around the world, but it turned out to not be as nasty as we feared. Bush administration into federal agencies that support vaccine research like BARDA and rapid flu vaccines, and the vaccine plant here in Holly Springs had us an H1N1 vaccine in record time.
I just hope the lessons we all learn, not just scientists, stick with us for a while. I was just looking for a bottom line summary that I could give my wife during a commercial break and get back to watching our show after I was quickly able to give her the answer. For example, like if they do an autopsy on a body that just died from COVID, how long does it take for special handling procedures, or even special social distancing of the body until the virus is technically not able to infect someone else?
Very informative even to someone without medical background. Answered all my questions. The idea that a universal influenza vaccine is being developed is very reassuring. Thank you! I have studied and watch news and science programs. We in the USA failed to have informed and enforced mask , social distant, testing , tracking , isolation. Gupta and models are similar. A idea may floor heat , crack a window in crowd room create a vent.
All safety as above also. Heard immunity is bad plan. President Obama had a plan when he left office. President Trump has been negligently. President Trump has been negligently, has weaken the nation, and should be charged for being a failure on handling this virus.
If viruses made an evolutionary leap away from the cellular form, casting off its weighty metabolic shackles to opt for a more streamlined existence, did they cease to be life? Have they reverted to mere chemistry? They all have surprisingly complex replication life cycles, however; they are exquisitely adapted to deliver their genomes to the site of replication and have precisely regulated cascades of gene expression.
Viruses also engineer their environment, constructing organelles within which they may safely replicate, a feature they share with other intracellular parasites. Fundamental to the argument that viruses are not alive is the suggestion that metabolism and self-sustaining replication are key definitions of life. Viruses are not able to replicate without the metabolic machinery of the cell. No organism is entirely self-supporting, however — life is absolutely interdependent.
There are many examples of obligate intracellular organisms, prokaryote and eukaryote that are critically dependent on the metabolic activities of their host cells. Humans likewise depend on the metabolic activity of nitrogen-fixing bacteria and photosynthetic plants along with that of our microbiota.
There are very few if any forms of life on Earth that could survive in a world in which all chemical requirements were present but no other life. So, what does define life?
Some have argued that the possession of ribosomes is a key ingredient. This draws a neat distinction between viruses and obligate intracellular parasites such as Chlamydia and Rickettsia. This definition also confers the status of life on mitochondria and plastids, however. The endosymbiosis that led to mitochondria is thought to have given rise to eukaryotic life. Mitochondria have metabolic activity on which we depend, they have machinery to manufacture proteins and they have genomes.
Most would accept that mitochondria are part of a life form, but they are not independent life. I would argue that the only satisfactory definition of life therefore lies in the most critical property of genetic heredity: independent evolution.
Life is the manifestation of a coherent collection of genes that are competent to replicate within the niche in which they evolve d. Viruses fulfil this definition. It is estimated that there are 10 31 virus particles in the oceans — they vastly outnumber all other organisms on the planet. Alive or not, viruses are doing rather well!
University of Edinburgh [email protected]. Bamford, D. Evolution of viral structure. Theor Popul Biol 61, — Boyer, M. Phylogenetic and phyletic studies of informational genes in genomes highlight existence of a 4 th domain of life including giant viruses. Some researchers also suggest that living things must be able to respond to stimuli and evolve over time.
Viruses can't generate their own energy, and though they can reproduce and even evolve with the assistance of a host, those functions are impossible for one of the tiny entities out on its own.
Instead, Albert Erives of the University of Iowa suggests that viruses are more like vines wrapping around the many branches of the tree of life. They can access and infect critters on each branch, racing to the top to evolve as their hapless hosts morph over time. All rights reserved. Bacteriophage viruses infect and replicate within bacteria, essentially taking them over.
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