A treatment for COVID-19? As of May 1, there are over 3 million cases of COVID-19 diagnosed worldwide, with more than 1 million of those cases located in the United States. The coronavirus pandemic has shut down massive sectors of the world economy and instigated quarantines in nearly every country. It’s a big feat for Mark McBride a microscopic package of chemicals. That’s really all a virus is, said UWM microbiologist Mark McBride – a package of proteins and nucleic acid that lies inert on its own but can hijack a living cell and take it over. “And then it’s off to the races and it starts (replicating),” he said. “In a matter of minutes to hours, you’ll have thousands or tens of thousands of virus particles assembling inside of that cell and then being released and infecting nearby cells.” McBride is a distinguished professor of biological sciences at UWM. Though his primary research focus is on bacteria, he knows a thing or two about viruses. Though the virus that causes COVID-19, called SARSCoV-2, is particularly infectious, it’s a virus that works just like any other. How a (corona)virus works A virus spreads when a virus particle injects itself into a living cell. Unlike bacteria, which are single-celled organisms that can reproduce on their own, a virus is classified as “non-living” and reproduces itself by taking over a living cell – “Like a pirate,” McBride said – and using that cell’s organelles to replicate its own genome.
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genetic information, RNA contains instructions for creating proteins. Once the virus has made its RNA to replicate its proteins, it starts to copy its genome over and over, using the living cell like its own factory. Some viruses then “lyse” the cell, or burst through the cell to escape and infect other cells, thereby killing it. But others, including David Frick coronavirus, make a gentle exit, stealing a piece of the cell’s membrane on its way out to form a lipid coating around itself, like an envelope of fat. It leaves the cell intact so it can continue making more virus particles. “There are plenty of viruses like that,” McBride said. “HIV and influenza are good examples. They can release not just thousands of viruses; they can release hundreds of thousands, or millions of viruses before the cell dies. It’s a strategy that works for the virus, and not necessarily so well for you.” Common and un-common infections Most people are familiar with several classes of viruses. People line up for the flu shot each year to protect against the ever-evolving strains of the influenza virus, and bemoan cold sores from the herpes virus. If you’ve ever had a cold, you’ve probably played host to a rhinovirus. But after rhinoviruses, coronaviruses are probably the second-most common cause of the common cold, McBride said.
Some virus genomes contain DNA, just like humans, plants, and animals, but others, including coronavirus, have genomes composed entirely of ribonucleic acid, or RNA. Unlike DNA, which codes all of an organism’s
“Of course, there are some coronaviruses that are much nastier,” he added. “All the ones that we know of that have this nastier trait jumped recently from animals. Closely-related viruses to the ones that infect humans – the SARS virus from more than a decade ago and the current pandemic virus (SARS-CoV-2) – are recognizably similar to viruses that are typically confined to wild animals like bats, for example.”
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Illnesses that jump from animals to people are called zoonotic diseases, and they generally occur because
