Differences Between Bacteria and Viruses

Categories of Antimicrobial Agents

Differentiating between viruses and bacterial infections is absolutely critical to give a patient adequate treatment. Antibiotics such as penicillin and its derivatives will not work on a viral infection. Not only are antibiotics ineffective against viruses; they are actually harmful given that overuse of antibiotics can give rise to antibiotic-resistant infections, both in the patient and in society as a whole. Primary care providers are on the front lines of fighting over-prescription of antibiotics and ensuring that antibiotics are prescribed solely for conditions for which they are effective and necessary.

"Bacteria are single-celled microorganisms that thrive in many different types of environments" (Steckelberg 2015). While many kinds of bacteria are harmless, some can be very dangerous, such as the bacteria that cause strep throat, tuberculosis, and urinary tract infections (Steckelberg 2015). In contrast, "when a virus enters your body, it invades some of your cells and takes over the cell machinery, redirecting it to produce the virus" (Steckelberg 2015). Viruses include the common cold, influenza, and HIV / AIDS (Steckelberg 2015). Bacterial infections usually have a clear initial treatment in the form of antibiotics. However, viruses are extremely difficult to treat. Notoriously there is no real cure for the common cold other than rest and fluids. "Viral infections are hard to treat because viruses live inside your body's cells. They are 'protected' from medicines, which usually move through your bloodstream ... There are a few antiviral medicines available," such as Tamiflu, but these are only used when the symptoms of influenza become very severe on in small children and the elderly who have a higher risk of complications from viruses ("Viruses," 2015).

Over-prescribing of antibiotics is a serious problem. Patients with a virus are often so desperate to feel better they may pressure doctors to prescribe them medication just in case or before tests come back confirming the real cause of their illnesses. Patients may also self-diagnose, order antibiotics off of the Internet, or borrow some from a friend who has leftover antibiotics. This highlights another problem: even when correctly prescribed, patients may not take antibiotics correctly and discontinue use when they feel better, not realizing that the full course of treatment is prescribed for a reason, to eradicate the bacteria from their system so it does not reassert itself with a resistant strain.

In contrast to bacterial infections, the only truly effective treatment for viruses is not to get them at all, which is why vaccines have been developed and are recommended for so many viral illnesses, including chicken pox and the flu. So many strains of the flu exist, however, that seasonal vaccination is necessary ("Key facts," 2015). According to the Centers for Disease Control (CDC), "the body's immune response from vaccination declines over time, so an annual vaccine is needed for optimal protection. Second, because flu viruses are constantly changing, the formulation of the flu vaccine is reviewed each year and sometimes updated to keep up with changing flu viruses" ("Key facts," 2015). Even if the initial illness has passed, viruses can still reassert themselves. Chicken pox, for example, can mean that an older adult may develop shingles. "The virus that causes the infection, varicella zoster virus, remains latent in nerve cells" (Allen 2011). With age, the individual's immune system becomes weaker and the virus can reassert itself. That is why it is so important to vaccinate versus relying upon natural immunity for the chicken pox; or, if the individual has already contracted the disease (as is the case with many older adults who came of age before the relatively recent chickenpox vaccine was developed)