preview

The Importance of Vaccines

According to the Merriam-Webster Dictionary, a vaccine is defined as a preparation of killed microorganisms, or living, virulent organisms that is administered to produce or artificially increase immunity to a particular disease. There are approximately fifty principle vaccines utilized in the United States to prevent bacterial and viral diseases in humans. Disease prevention is a primary concern of public health in the U.S. Over the past two centuries, vaccines have been successful in preventing numerous cases of infectious diseases including: polio, measles, diphtheria, pertussis (whooping cough), rubella (German measles), mumps, and tetanus. In fact, it was a vaccine that was responsible for the eradication of smallpox, one of the most injurious diseases, in 1977.
The immune system plays a vital role in the fight against infectious diseases. It is capable of identifying pathogens that enter the body as foreign “invaders”, or antigens. This, in turn, signals the production of large, Y-shaped proteins called immunoglobulins (antibodies), which are used to pinpoint and neutralize these foreign substances. Vaccines contain the same antigens that cause disease; however, they are attenuated so that they are not strong enough to cause disease, but are able to stimulate the immune system to produce antibodies against them. In essence, vaccination protects against disease by triggering the immune response against a specific pathogen. Through vaccination, people are able to develop immunity without suffering from the actual diseases that vaccines prevent.
Herd immunity is described as the resistance of a population to infection and to spread of an infectious organism due to the immunity of a large percentage of a population. The lev...

... middle of paper ...

...faces. This is because, during transmission, HPV targets proliferating cells of the epithelium. Once inside the epithelial cell, the viral genome begins to replicate. Subsequently, the HPV particles that are released are able to infect a new host and the process repeats.
The “high-risk” potential of the HPV type is mediated primarily virulence factors which include E6 and E7 proteins. These proteins have been shown to bind to and degrade tumor-suppressor protein p53 and retinoblastoma (Rb) protein, leading to the inhibition of gene expression of normal cell division. The inactivation of p53 affects apoptosis of cells at the G0 checkpoint and results in cell cycle arrest. When E7 binds Rb, the Rb-E7 complex is degraded and the cells proceed to divide at an unregulated rate. This uncontrolled division is responsible for the malignant cells found in cervical cancer.
Get Access