A Virus Is Just A Virus
Or Is It?
Have you ever noticed that when you ask someone who is sneezing, coughing, and sounds congested what is wrong he or she never responds, “just a cold?”
The response is usually more on the order of “I have a head cold,” “I have a chest cold,” “it’s in my sinuses,” or “I have the flu.” Having a cold just doesn’t seem serious enough to explain how terrible we feel under these circumstances.
In fact, the common cold is just that, a cold. There is no difference between “just a cold” and a “chest cold” or “terrible head cold.” Most colds do not develop into sinus infections or bronchitis. The “flu” is a completely separate illness.
Colds are caused by a number of different viruses, the most common being rhinovirus. The technical term for the common cold is viral upper respiratory infection (URI). Although colds are usually self-limited and do not have serious consequences, people who have colds feel terrible for good reason: the virus infects the throat, nose, and mouth, causing a response from the body’s immune system that causes inflammation, swelling, and most of the symptoms we experience . Because there are over 200 different viruses that cause colds, it has not been possible to develop treatments or vaccines.
Is It Time to Bring Out the Big Guns?
When people feel sick with a cold for about a week, they frequently start to worry that something more serious is happening and go to the doctor. That’s not necessarily the wrong thing to do if high fever persists, an earache develops, or the cold triggers an asthma attack. But usually, it’s just the lingering effects of the immune response to the cold virus and the doctor should do nothing but offer reassurance.
Unfortunately, all too often patients insist on being given antibiotics when all they have is a viral URI. The cold has gone on long enough, they believe, and it must be time to bring out the “big guns.” Even more unfortunately, physicians often go along with those requests and prescribe them. At least one-quarter of antibiotic prescriptions are unwarranted according to a recent study. Every year public health officials and academic medical scientists produce data showing that antibiotics are overprescribed, but year after year the data continue to show that patients and doctors don’t heed the warnings. Colds are one of these instances in which antibiotics have absolutely no place.
The reason for this is that antibiotics treat infections caused by an entirely different type of organism, bacteria. No matter how severe a viral infection is, antibiotics like amoxicillin and azithromycin (often called the Z-pack) have absolutely no effect. Giving someone antibiotics for a viral infection is essentially like trying to turn a screw with a hammer; it’s just the wrong tool.
But the idea seems to linger in people’s minds that when a common illness like the cold gets really bad or takes too much time to go away, it can’t be from “just a virus” but must be caused by something more serious, something that requires medications that can only be prescribed by a doctor or other licensed prescriber.
Antibiotic Overprescribing is a Serious Problem
The problem of antibiotic overprescribing is a serious one. Bacteria, the true targets of antibiotics, are everywhere but cause disease only sometimes. When faced with antibiotics, those potentially disease-causing bacteria that linger in our bodies can and do mutate to forms that are resistant to antibiotics. This has led to an abundance of disease-causing, antibiotic-resistant strains of bacteria that make treating conditions like pneumonia, tuberculosis, gonorrhea, and salmonella infection increasingly difficult. The World Health Organization (WHO) regards antibiotic resistance as one of the most serious threats to health in the world today. Overuse of antibiotics is also one of the causes of gastrointestinal illness caused by the bacteria commonly called C. diff.
It is therefore important for us to understand what the difference is between viruses, bacteria, and other disease-causing infectious agents. Furthermore, it is critical for people to understand that viruses are fully capable of causing serious and even life-threatening disease, so it is not correct that an illness is being trivialized when it is ascribed to “just a virus.”
How Bacteria and Viruses Differ
Bacteria are single-cell organisms that usually (but not always) have a cell wall around them. An example of a illness-causing bacteria is called Group A Streptococcus, the cause of “strep throat,” a condition that often occurs in children and requires antibiotics to prevent serious complications. Antibiotics treat bacterial infections in one of two main ways, either by killing bacteria directly or by preventing bacteria from multiplying (also called “replicating”). Among the conditions that are caused by bacteria are some forms of pneumonia, meningitis, and urinary tract infections, syphilis, Lyme disease, and tuberculosis. On the other hand, bacteria can be helpful, as is the case with many bacteria that normally live in the gastrointestinal tract and aid in digestion. Overuse of antibiotics kills beneficial bacteria and can be a cause of gastrointestinal illness.
A picture of a bacterial infection. Each bacterial cell is a living organism that can reproduce and make energy on its own.
Bacteria are independent organisms that can be seen by using high magnification light microscopes, make their own energy, and can reproduce on their own. They can survive for long periods of time outside of a host, like the human body. Viruses, on the other hand, are much smaller than bacteria, cannot be seen by light microscopes, and do not make their own energy. Although they can also live outside of a host for short periods of time, they cannot reproduce on their own and their survival is ultimately dependent on infecting another organism and hijacking its genetic and energy machinery. Some viruses actually infect bacteria in order to do this. Technically, bacteria are living organisms, whereas viruses are just pieces of genetic material (DNA or RNA) surrounded by a membrane.
Viruses infecting a human nerve cell (neuron). Viruses cannot reproduce or make energy on their own and must infect a living cell in order to survive and spread infection.
These differences are critical in terms of treating infections. Because antibiotics do not work on viruses, scientists have had to use a whole set of different approaches to develop medications that treat viral infections. These drugs generally interfere with the viruses’ ability to enter human cells or, when they do enter, to attach themselves to the human cells’ genetic material and reproduce. This strategy has been remarkably successful in the case of some viral infections, like HIV and hepatitis C. There are also antiviral medications that lessen the severity of some viral infections. Acyclovir is prescribed for people who have some forms of herpes infections, for example. There are currently four antiviral agents approved for the treatment of influenza (the flu) by the FDA. These drugs, like Tamiflu and Relenza, do not “cure” flu, but can lessen the length of illness, the severity of symptoms, and the risk of complications.
Prevention is currently the best strategy for dealing with most viral illnesses. If you do have a cold, washing your hands frequently and covering your nose and mouth when you sneeze or cough will help prevent transmitting the virus to other people. Not having unprotected sex or using intravenous drugs will prevent HIV and hepatitis C infections. And getting vaccinated for viral illnesses is, of course, essential.
The Resistance to Vaccinations
Some people continue to believe that viral illnesses are not serious enough to warrant vaccination. It has recently been noted, for example, that some parents are using social media to “set playdates for their children who don’t have chickenpox, with other kids who do, in the hopes that they’ll contract the illness”. These parents apparently reason that because chickenpox is usually a self-limited illness for children, it is better for them to get it early in life and develop “natural immunity.” They seem to believe that there is a greater health risk from the chickenpox vaccine than from the illness itself. In other words, since chickenpox is “just a virus,” that doesn’t usually cause lethal complications, why risk giving a child a vaccine?
Now if it were true that chickenpox is an entirely benign illness and that there are significant health risks with the vaccine, these parents would of course have a good case. But neither assertion is true. Although chickenpox is usually a mild illness in children, it is extremely unpleasant—a child infected with the varicella zoster virus that causes chickenpox is miserable for 10 to 14 days. And for some, severe complications can set in. These include pneumonia, encephalitis (brain infection), dehydration, and sepsis. Most vulnerable to these complications, which can be fatal, are infants, adolescents, adults, people who have a compromised immune system, and pregnant women. For example, if a child with leukemia undergoing chemotherapy contracts chickenpox, the child can die.
And as most people know, although after having chickenpox you usually cannot get it again, the virus remains in a latent state in the nerve terminals of the body, only to reawaken many years later and cause a painful and debilitating disease called shingles. The pain from shingles can persist even after the blisters disappear, a condition called postherpetic neuralgia.
The chickenpox vaccine was introduced in 1995 and is safe. It eliminates the chance of getting both chickenpox and shingles. Severe reactions to the vaccine are extremely rare, far less common than complications of chickenpox itself. Clearly, children should receive the chickenpox vaccine in order to protect them and others in the community from potentially serious complications.
We Should All Know the Basic Differences
There are other disease-causing microorganisms besides viruses and bacteria. Thrush, athlete’s foot, ringworm, and pneumocystis pneumonia are all caused by different kinds of fungi and have their own specific medications for treatment that are different from those used to treat bacteria and viruses. Malaria is caused by a parasite and mad cow disease by a strange pathogen called the prion.
It isn’t necessary for everyone to become experts in microbiology and infectious diseases to know the names of all the different germs that make us sick or to be able to sort out which medications are used for which types of infections. But increasingly it is clear that everyone needs to know that viral infections are not the same as bacterial infections, can make us very sick and cannot be treated by antibiotics. Solidifying those three pieces of information in the public’s mind could go a long way toward improving our collective health by encouraging people to vaccinate themselves and their children against viral illnesses and to stop demanding antibiotics for conditions caused by viruses.
So next time you are coughing and sneezing, your nose won’t stop running, and a friend asks you if you are sick, you might respond: “I sure am. I have a cold. It is making me feel awful and there is nothing I can do but stay hydrated, get rest, and wait for it to go away in a week or two. Thank goodness I had my flu shot so even if this is the flu, I shouldn’t get too sick. Hope you’ve had yours.”