Viruses play a significant role in day-to-day life, even though they are so tiny that they can’t be seen with the naked eye. The COVID-19 global pandemic is a current example of this, as the coronavirus has led to the closures of businesses, schools, and public spaces all over the world.
For billions of people around the globe, viruses are at the forefront of their minds right now. That’s why it’s important to share information about what viruses are, how they are structured, and how they spread between people. In this post, we will cover all of those vital topics and more.
What are viruses?
Viruses are a form of microbes, which are microscopic living things that exist all around the world, in air, water, and soil. Other examples of microbes include bacteria and fungi. Some microbes, like the bacteria Lactobacillus acidophilus, also live within the human body and help keep people healthy. However, other microbes can be seriously harmful to people — like some viruses.
How are viruses structured?
Viruses are the smallest type of microbes. According to the Microbiology Society, viruses are so small that “500 million rhinoviruses (which cause the common cold) could fit on to the head of a pin.”
Technically, viruses are not living organisms. Unlike some other microbes, viruses do not have cells. Instead, they contain genetic material (DNA or RNA), as well as a protective outer layer called the capsid, which is made from protein. The small size of a virus allows it to infiltrate healthy host cells, where it relies on the cell’s machinery to replicate itself. Without host cells, a virus would not be able to make copies of itself.
How do viruses affect people?
Different viruses can affect people in many different ways. For example, the influenza A and B viruses infect people with the flu every year. For many, flu symptoms will resolve themselves with rest and proper care. But for others, this virus can be deadly.
Similarly, the world is now grappling with COVID-19 (also known as coronavirus disease). People who have been infected with COVID-19 often experience respiratory illness and other symptoms like fever and cough.
Another example is the varicella-zoster virus, which causes chickenpox and shingles. These viral infections are highly contagious and cause itchy and painful blisters on the skin.
How do viruses spread?
People can transmit viruses to one another quite easily, especially in enclosed spaces. The main way that this happens is through coughing and sneezing. When a person has been infected with a virus, the droplets contained within their coughs and sneezes contain particles of the virus. If those particles come into contact with another person’s nose or mouth, they may become infected.
Viruses (including SARS-CoV-2, the virus that causes COVID-19) can also live on plastic and steel surfaces for two to three days. If someone were to touch a contaminated surface and then touch their eyes, nose, or mouth, they also run a risk of infection. This is why handwashing is critical to prevent the spread of this virus.
For more biology-related content, check out the Biology Wise blog.