The Viral Storm Read Online Free

bacteria, the usual suspects for transmissible disease at the time, would be too large to pass through. Something else must have caused the infection—something unknown and considerably smaller than everything else recognized to be alive in his time.

    Dr. Martinus Beijerinck. ( Undated photo )
    Unlike his colleagues, many of whom believed a bacteria would emerge as the cause, Beijerinck concluded that a new form of life must cause tobacco mosaic disease. 1 He named this new organism the virus , a Latin word referring to poison. The word virus had been around since the fourteenth century, but his use was the first to link it to the microbes to which it refers today. 2 Interestingly, Beijerinck referred to viruses as “contagium vivium fluidum,” or “soluble living agent,” and felt they were likely fluid in nature. That is why he used the term virus —or poison—to denote its “fluidity.” It wasn’t until later work with the polio and foot-and-mouth-disease viruses that the particulate nature of viruses was confirmed.
    In Beijerinck’s time a new microscopic perspective began revealing itself to scientists. Looking through microscopes and applying gradually smaller filters, these microbiologists realized something that continues to amaze us today: shielded from our human-scaled senses is a wide, teeming, startlingly diverse, unseen world of microbial life.
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    I teach a seminar at Stanford called Viral Lifestyles. The title was meant to evoke curiosity among prospective students but also describe one of the course’s objectives: to learn to envision the world from the perspective of a virus. In order to understand viruses and other microbes, including how they cause pandemics, we need to first understand them on their own terms.
    The thought experiment that I give my students on the first day is this: imagine that you have powerful glasses allowing you to perceive any and all microbes. If you were to put on such magical bug-vision specs, you would instantly see a whole new, and very active, world. The floor would seethe, the walls would throb, and everything would swarm with formerly invisible life. Tiny bugs would blanket every surface—your coffee cup, the pages of the book on your lap, your actual lap. The larger bacteria would themselves teem with still smaller bugs.
    This alien army is everywhere, and some of its most powerful soldiers are its smallest. These smallest of bugs have integrated themselves, quite literally, into every stitch of the fabric of earthly life. They are everywhere, unavoidable, infecting every species of bacterium, every plant, fungus, and animal that makes up our world. They are the same form of life that Beijerinck found in the late days of the nineteenth century, and they are among the most important of the microbial world. They are viruses.
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    Viruses consist of two basic components, their genetic material—either RNA or DNA—and a protein coat that protects their genes. Because viruses don’t have the mechanisms to grow or reproduce on their own, they are dependent on the cells they infect. In fact, viruses must infect cell-based life forms in order to survive. Viruses infect their host cells, whether they are bacterial or human, through the use of a biological lock-and-key system. The protein coat of each virus includes molecular “keys” that match a molecular “lock” (actually called a receptor) on the wall of a targeted host cell. Once the virus’s key finds a matching cellular lock, the door to that cell’s machinery is opened. The virus then hijacks the machinery of that host cell to grow and propagate itself.
    Viruses are also the smallest known microbes. If a human were blown up to the size of a stadium, a typical bacterium would be the size of a soccer ball on the field. A typical virus would be the size of one of the soccer ball’s hexagonal patches. Though humans have always felt virus’s effects, it’s no wonder it took us so