What opportunities do viruses have to start multiplying rapidly?

We invite you to read an excerpt from Bill Bryson’s book “The Body. A Guide to the Human Body”.

Microorganisms and you

The virus, according to British Nobel Prize winner Peter Medawar, is “packed with protein.” In fact, many viruses are not bad at all, at least for humans. Viruses are strange, not quite alive, but they are certainly not dead. Outside the living cell, they are inert. It is not mentioned, it does not breathe, it does nothing. There is no way to move. They can’t travel alone, so hitchhiking. We need to pick them up ourselves: from the door handles, waving and pressing the hand, inhaling air. Most of the time, they show no signs of life like dust, but are barely found in a living cell, just as all living creatures begin to reproduce furiously when they revive.

Like bacteria, viruses are incredibly successful. The herpes virus has spread for hundreds of millions of years and infects a wide variety of animals, including edible oysters. Viruses are also indescribably tiny, much smaller than bacteria and too small to see through ordinary microscopes. If you amplified a virus to the size of a tennis ball, a man of the same scale would be five hundred kilometers tall. And the bacteria is like a beach ball.

The term “virus”, which now refers to a very small microorganism, dates back to 1900, when Dutch botanist Martinus Beijerinck discovered that the tobacco plants he studied were not resistant to a mysterious infectious agent, even smaller than bacteria. . He originally called the mysterious pathogen live fluid contaminationcontagious, live fluid, but later renamed virus, a Latin word that means poison. Martin Beijerinck became a pioneer of virology, but in life no one appreciated the importance of this discovery, so he did not receive the Nobel Prize, although he certainly deserved it.

All viruses were thought to cause disease, the same goes for a Peter Medawar quote, but we now know that many viruses infect only bacterial cells and do not affect us at all. It is logical to assume that there are hundreds of thousands of species of viruses, but only 586 infect mammals, of which only 263 harm humans.

We know very little about other non-pathogenic viruses, because we tend to study those that cause disease. 1986 Lita Proctor, a student at Stoney Brook University in New York State, decided to look for viruses in seawater, a very eccentric idea, as there is a general belief that there are no viruses in the oceans unless the other is temporarily there through sewers and the like. So everyone was a bit surprised when Proctor discovered that, on average, there are up to one hundred billion viruses per liter of seawater. Not long ago, Dana Willner, a biologist at San Diego State University, found out how many viruses are in the lungs of a healthy person, because there are not considered to be many of them.

Willner found that a person carries an average of 174 types of viruses in their lungs, 90 percent of which had not been seen before. We now know that the Earth is teeming with so many viruses that we couldn’t have imagined recently. According to virologist Dorothy H. Crawford, if we were to align just the ocean viruses, it would be ten million light years away, a practically incomprehensible distance.

Viruses have one more thing: they are waiting for a good opportunity. The most unusual example is the 2014 story that happened when a team of French researchers in Siberia found a previously unknown virus. Pithovirus sibericum. It had been in permafrost for thirty thousand years, but as soon as scientists inserted it into the amoeba, it was revived as the youngest youngster. Fortunately, it turned out that P. sibericum it doesn’t endanger humans, but who knows what other viruses are waiting to be found? A much more common example of such patience is Varicella zoster virus. In children, it causes chickenpox, but then it can remain in nerve cells for half a century or more, and in old age, an unpleasant and painful disease called shingles flares up again. This is usually an extremely painful rash on the waist, but in reality the blisters can break out of the body almost anywhere. For my friend, they appeared in his left eye, and he says it was the scariest thing in his life. (By the way, the name shingles comes from the Latin word cingulus, which means “bar”).

Usually we find unwanted viruses when they are frozen. Everyone knows that a cold can cause a cold (which is why we say we catch a cold after a cold), but science has never been able to prove why, and even or, it actually happens. We cool off more often in winter than in summer, but perhaps only because we spend more time indoors, which protects us less than others exhale, sneeze, or suck on. Colds are not a single disease, but a family of symptoms caused by many viruses, the most malignant of which are rhinoviruses. There are a hundred strains of this type of virus alone. So, in short, colds are caused by a large number of viruses, so you will never get enough immunity that any of them infect you.

For many years there was a research center in the county of Wiltshire in Great Britain called Common cold unit (Division of cold sores), but in 1989. it was closed without finding a cold medicine. However, interesting experiments were conducted on it. Through one of them, the volunteer connected a device that dripped fluid into his nostrils like a runny nose. That volunteer then interacted with other volunteers without comparing during a cocktail party. None of them knew that there was a tint in the liquid that was only visible under ultraviolet light. When all the participants turned it on, they were all surprised to see that the paint was everywhere: on the hands, head and upper body of each participant, on the cups, the door handles, the cushions of the couches, a bowl of nuts, whatever we call it.

The average adult touches his face sixteen times an hour, so during the experiment, each time he touched something, the imaginary pathogen was transferred from the nose to the snack bowl, from the bowl to the unoccupied guest, from there to the handles. from the doors, from them, to the unoccupied. another guest and so on until essentially all things and people solemnly glowed with imaginary tobacco. In a similar study, researchers from the University of Arizona infected a metal door handle in an office building and found that in just four hours, the “virus” spread throughout the building, infecting more than half of workers and settling in all shared facilities, such as photocopiers or coffee makers. It is true that this infection remains active for up to three days. Interestingly, the most ineffective way to spread germs (according to another study) is kissing. Kissing turned out to be almost harmless, and this was tested by volunteers from the University of Wisconsin who were infected with viruses that infect the cold before kissing. With sneezing and coughing, almost the same. The only truly reliable way to spread colds is through physical contact.

A study on Boston subway trains showed that metal rods are a relatively hostile environment for microorganisms. Instead, they thrived on the seat upholstery and plastic handles. The microbes appear to distribute themselves most efficiently through a combination of paper money and nasal secretions. A study in Switzerland revealed that the flu virus can survive on a banknote for two and a half weeks if it finds even a microscopic spot in the spring. Without sneezing, many cold viruses survive on paper money for no more than a few hours.