Advantages and Disadvantages of Vaccines - Essay Example

Traditionally, living or dead pathogens were used as vaccines; however, in modern times Immunologists have found improved ways of fashioning vaccines, one of which is the Subunit vaccine. We know that vaccines are made up of specific microbes which help immunize our body against specific diseases. In Subunit Vaccines, as the name suggests, only the specific fragment of a microbe or an infectious agent (Thecochranelibrary.com, 2014). These fragments might be epitopes which are specific parts of an antigen that are easily recognizable to the antibodies or T cells.

Subunit vaccines consist of about 1-20 or sometimes even more antigens, whereas it is an intense task to specify which antigen would prove the most efficient stimulator (Flower and Perrie, 2013). There are two ways of manufacturing these vaccines once the appropriate antigen has been identified:

• The microbe can be grown in the laboratory and the fragments can then be collected
• The antigen molecule itself can be manufactured with the help of recombinant technology

Why Subunit vaccines are considered safer
All vaccines go through a careful evaluation to make sure that they are safe for consumption; however, there are some flaws in the structure of traditional vaccines that were illuminated with the creation of subunit vaccines. Usually, inactive pathogens are introduced into the immune system of a human being as a vaccine; being inactive means that the pathogen can no longer cause disease because the viral fragment has been deactivated. The one problem with this procedure is the chance of reversion. Reversion is the process by which a microbe undergoes genetic changes, converting it into an even deadlier threat to the human body (Vaccine-safety-training.org, 2014).

This risk is eradicated in the case of subunit vaccines because only the structural fragments of a pathogen are used, which means that there can be no genetic changes, hence no damage to the human body may occur (Stratton, Wilson, and McCormick, 2002).

Another shortcoming of traditional live vaccines is that they cannot be used by certain groups of people, such as the elderly above 65 or even pregnant women. This is because even attenuated viruses can pose a threat to the health of these people, making it fatal for them to use these vaccines. Similar to the case before, subunit vaccines are introduced in the body as small fragments rather than a whole microbe so they pose no real threat to people with weak immune systems (Plotkin, 2010).

Advantages of Subunit Vaccines

• The advantages of subunit vaccines include the fact that the whole microbe is not used, this means that no genetic components of the microbes are introduced in the body hence no adverse effects can take place.
• These vaccines can be used on people who are immune-compromised with no fear of reversion.
• Another advantage of subunit vaccines is that they do not require being grown in a laboratory culture, making them more feasible and easier to handle.

Disadvantages of Subunit Vaccines

• One of the foremost disadvantages of subunit vaccines is that they are not as effective as live vaccines, where live vaccines are given in about 2-3 dozes, subunit vaccines need to be taken periodically over a longer period of time.
• It is a lengthy process to increase the effectiveness of subunit vaccines because it requires the presence of carriers to form conjugate vaccines.
• Some diseases need more than one protein fragment of a pathogen in vaccines in order to be suppressed, so subunit vaccines with only one fragment of these surface proteins are not efficient.
• It is a time-consuming process to determine which pathogen or which exact fragment needs to be used for which specific disease (Learn.genetics.utah.edu, 2014).

Applications and Examples of Subunit Vaccines

• Subunit vaccines are being used as potential immunization for Hepatitis B, which is interestingly made of particular fragments of the Hepatitis B virus as well as household yeast.
• Another use is for Hepatitis C, also called whooping cough.
• Herpes Simplex