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Antiviral Drugs V.S. Vaccines

Ever since the beginning of the COVID-19 pandemic, scientists, researchers, and medical professionals from around the world have been working tirelessly to develop a vaccine to combat the virus. Although have been many significant developments and successes with this process, many are still skeptical about getting the COVID vaccine. A survey shows that over 10% of respondents say they are "afraid of needles" and prefer to take an orally administered drug. This article will discuss the key differences between an antiviral drug and a vaccine and which method is more effective in combating viruses.

Image courtesy of The Scientist Magazine.


What are Vaccines?

In simple terms, vaccines are biochemical formulations that offer immunity to a specific disease for a certain period. Vaccines contain the same bacteria that cause infection (for example, the measles vaccine contains the measles virus), but they are weakened, so they cannot defile your body. Vaccines trigger the immune system to produce antibodies just as it would if you were subjected directly to the illness. Therefore, after you get vaccinated, your body develops immunity to the virus, making vaccines more effective than other treatment forms.

Methods of Administration

Despite the common perception, vaccines are not always administered in the form of needles. Although it is the most popular form of administration, vaccines can also be delivered orally or through nasal sprays.

How Do Vaccines Work?

By administering a vaccine, the immune system is stimulated in ways that allow it to develop defenses against specific disease agents. The body's immune system defends against pathogens, which are substances capable of causing infection. A vaccine poses as a pathogen imposter to the immune system; it looks and behaves like a bacteria or virus would, but does not make the body sick. Antigens are molecules that are present on the surface of pathogens, and they trigger an immune response. Vaccines expose the body to antigens similar to those found on pathogens. By posing as a specific pathogen, the vaccine prepares the immune system to react quickly and forcefully if it encounters that pathogen in the future.

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Antiviral Drugs

What are Antiviral Drugs?

Antiviral drugs are a type of medication designed explicitly to treat viral infections. Most antivirals focus on specific viruses, while a broad-spectrum antiviral is efficacious against heterogeneous pathogens. The antiviral drugs currently available for use are designed to target three different viruses classes—hepatitis, herpes, and influenza viruses—although they are most commonly used as the second line of defense against the flu (the first being the flu vaccine).

Methods of Administration

Antivirals can be administered in a variety of ways. The most common administration method is oral administration, although nasal sprays, inhalers, or insertion can also be used to administer the medication.

How Do Antiviral Drugs Work?

Antiviral drugs work by slowing down and ultimately stopping the infection process. The blocking of this process, depending on the infection and medication, can occur at varying regions. An inhibitor blocks a receptor that binds the pathogen to the healthy cell by preventing the virus from fusing with it. Antivirals interfere with an essential enzyme of the infection. They prevent the virus from escaping from one cell to infect a neighboring cell.

Difference between Antiviral Drugs and Vaccines

The key difference between antivirals and vaccines is that a vaccine prevents a virus from infecting your body by providing immunity, while antivirals work to treat a virus that has already entered your body by slowing down the infection process. They are designed for two different purposes.

Which is more effective?

Research indicates that vaccines are safer and more effective than antiviral drugs. Vaccines are also more versatile than antiviral drugs and can be used against a greater variety of diseases, whereas antiviral drugs are limited to only three kinds of infections. However, antivirals may become a predominant treatment in the future as more research is undertaken.


Basics of Vaccines. (2012, March 14). Retrieved from https://www.cdc.gov/vaccines/vpd/vpd-vac-basics.html

How do vaccines work? (n.d.). Retrieved from https://www.who.int/news-room/feature-stories/detail/how-do-vaccines-work

Publishing, H. H. (n.d.). What you should know about antiviral drugs. Retrieved from https://www.health.harvard.edu/drugs-and-medications/what-you-should-know-about-antiviral-drugs

What are antiviral drugs? (n.d.). Retrieved from https://www.webmd.com/cold-and-flu/qa/what-are-antiviral-drugs

What are vaccines? (2020, May 19). Retrieved from https://immunizebc.ca/what-are-vaccines

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Article Author: Risheena Banerji

Article Editors: Maria Giroux, Olivia Ye