Immunizations or Vaccinations: What's the story? Published Aug. 22, 2011 By Dr. Jack M. Davis 99th Aerospace Medical Squadron Public Health Office NELLIS AIR FORCE BASE, Nev. -- The terms immunization and vaccination are both derived from Latin, and while many people use the words interchangeably, it is important to know that there is a slight difference between the two. Immunization is derived from the word immunis, which means free from or exempt. Ancient Romans originally used the word immunis to describe someone who was free from further taxation. Vaccination, on the other hand, comes from the Latin word vaccinus, which is an adjective that means of or from cows. This may seem like an unusual meaning for a word that refers to modern medicine, but the story of how this word came to be explains this odd derivation. In the late 18th century, an English physician by the name of Edward Jenner observed that dairymaids, or milkmaids, who developed cowpox did not develop smallpox. This observation was significant for two reasons. First, cowpox is a milder disease than smallpox and does not leave scars all over a person's body like smallpox does. (This is how the old saying, "as smooth as a milkmaid's skin" came about.) Second, cowpox did not kill people like smallpox did during that time. Based on his observation, Jenner tested an idea. In 1796, he took the fluid from a cowpox sore on a dairymaid's hand and inoculated an 8-year-old boy. Six weeks later, Jenner exposed that same boy to smallpox. The result: the boy did not become ill with smallpox. This discovery led to a vaccine that stopped smallpox, ultimately eliminating a disease that killed approximately 30 percent of the people who caught it. As medicine has developed over the years, doctors' and nurses' have been able to build on the foundation Jenner created regarding vaccines. Today, their understanding of the relationship between vaccinations and preventing illnesses is significantly heightened and is improving constantly. Based on this understanding, medical personnel have identified three approaches that will combat illnesses to varying degrees of effectiveness. Tertiary prevention is the most commonly used approach. This is when medical care is given to prevent the worsening of an illness and, ultimately, allow for complete recovery. It is considered an after-the-fact approach and is the least desirable way to deal with an illness. Secondary prevention is a better approach. This is when medical personnel discover an illness early in its course and take action to minimize its progress. While this approach is an improvement over tertiary prevention, there is still a possibility that the illness may have some deleterious effects on a person. The best approach is primary prevention. This allows medical personnel to intervene before an illness has any impact on a person. Primary prevention involves giving immunizations to people because immunizations awaken and strengthen the body's ability to defeat microbes before the illness spreads. To summarize: prevention trumps treatment as a best practice. One thing to remember is that each of today's immunizations is disease-specific. For example, the Hepatitis A vaccination provides immunity to the Hepatitis A disease but does nothing to stop the illness caused by the Hepatitis B virus. Thus, it is important to receive all immunizations necessary when at risk of exposure to an illness. Currently, there are 21 different illnesses against which Airmen can be protected through vaccination. Of these, 13 are diseases caused by viruses and eight are diseases caused by bacteria. Not all 21 vaccines are required, some are used only in certain circumstances, but each is worth getting. As the saying goes, "an ounce of prevention is worth a pound of cure." For more information regarding vaccinations or to schedule an appointment at the Mike O'Callaghan Federal Hospital here at Nellis Air Force Base, call 653-2733.