Terry M. Bella
Many attribute the initial practice of inoculation as being the work of Edward Jenner, but, in actuality the practice of infecting a person in order to protect them from a disease dates much further back. The particulars of the true history of inoculations is beyond the scope of this unit, but there is documentation of inoculations that pre-dates Jenner’s work by some 300 years or more. Those activities did also include activity with smallpox. A lesson on vaccines should include some history though, as the discovery of the process is important to the understanding of the result. Exposing the body to the infecting agent allows the body to learn of the pathogen and develop defenses against it. It was not known to those pioneers that they were dabbling with a precarious situation, but they were acutely aware of the fact that a forced exposure of some sort was better than contracting the disease unknowingly.
Edward Jenner is credited for first discovering the concept of vaccination because his work was well documented. Based on the premise that one that contracts the cowpox virus is then immune to the smallpox virus, Jenner inoculated a child with material from a cowpox pustule. He subsequently inoculated the boy with material from a smallpox pustule and when the boy did not contract the smallpox virus Jenner’s hypothesis was validated. His initial hypothesis was rooted in the occurrence of seemingly immune individuals. These individuals were milk maids who worked closely with cows and had contracted the milder virus of cowpox and were later unable to contract smallpox. What Jenner was not aware of was how this phenomenon worked which is the intent of this unit. Students should understand the potential of vaccines which requires an understanding of how we leverage the immune system through vaccination. Jenner was not aware that it was on a cellular-level that the body was “learning” about and preparing for the infectious agent and that it was an antigen (the identifying pathogenic factor) that was the key. The antigen is luckily the same for the cowpox virus as it is for the smallpox virus, thus Jenner’s inoculation worked. The body learned to defend against anything presenting the antigen and thus was able to mount an appropriately timely defense against a smallpox infection. The antigen is a specific molecule that is presented by the virus, in this case the molecule is identical between the smallpox and cowpox viruses.
Vaccines have immense potential, potential that is being realized with the near eradication of many debilitating and deadly diseases. Using the immune system to protect against pathogens has much more promise than using a drug. The ingestion of a drug will invariably have some collateral damage on the body, wherein the utilization of a targeted attack by the immune system does not have that potential threat. The pathogen is targeted at the molecular level. The immune system targets the specific molecule that it is hunting. Drug therapy, in contrast, is targeting a trait of a cell, traits that may be common to other non-target, non-pathogenic, cells. The premise of the action of vaccinations is now being applied to using vaccines to treat diseases, not only those that are of foreign origin such as HIV, but also cancers. This is essentially using the immune system as a weapon against a disease that the body has developed on its own. This is different than vaccinating against a disease that you have not yet contracted, wherein you are preparing the immune system for possible invasion by exposing to it something that is not actually able to cause a disease state. This new application is about mobilizing the immune system at times when it is not sufficiently mobilizing itself.