Vaccines—the ultimate accomplishment of modern medicine, the truest example of preventive care. Yet since their inception, there has been controversy and suspicion regarding their every aspect. Some people worry about the advisability of getting an injection when they are well now in order to prevent a disease they might get in the future. Others are concerned about provoking a system, the immune system, when we still are not 100 percent sure of all of the long lasting effects. There are those who worry that a mass campaign undertaken by a government to inoculate the population at large could be an Orwellian strategy to manipulate its citizens. And a few groups have religious objections, deeming sickness a deity-directed condition that should not be thwarted. It is hoped that better understanding of their mechanism of action will allay the majority of these fears and allow as many people as possible to benefit from what is felt to be the most powerful form of illness prevention current technology has to offer.
Vaccines help the immune system do a better job by causing it to create antibodies. Antibodies are an essential protein component of the immune system; there are millions of different types, each one specific for the individual entity it will help destroy. But it typically takes up to two weeks for the immune system to produce enough effective antibodies to vanquish an infection, and irreversible damage, spread to others, or even death can occur in that interval! Immunization prompts one’s immune system to produce disease-fighting antibodies in advance of illness exposure. An appropriately inoculated individual will therefore either not get the illness, or get a very mild variant—and, almost as importantly, there will be a marked reduction in the likelihood they will infect others. Thus, for both personal and public medical goals, vaccinations have become essential healthcare tools
Disease prevention by purposeful exposure to the disease-causing organism is not a new concept. Long before the individual components of the human immune system were identified and understood, there were strategies to harness and direct its power. Early in the eighteenth century, Turkish doctors used this concept to protect the royal family from the frequently fatal, always disfiguring scourge, small pox. They would lance a sufferer’s festering sore, carry the purulent matter to the palace, and inject a tiny amount in the skin under the arm of the royal family member. A nasty boil would ensue—with permanent scarring in this inconspicuous area—but so would lifelong protection from the full blown illness. Later that century, Edward Jenner and Louis Pasteur advanced this concept by offering patients protection from small pox by injecting fluid from a cow infected with a similar affliction called cow pox. (“Vacca” is Latin for “cow, and thus the term “vaccination” was born.)
Science has come a long way since then, though the underlying rationale remains the same. In some cases, researchers have successfully labored to identify the protein portion of the bacteria or virus—or of the damaging toxin that entity produces -- that, when administered to a person, will evoke formation of protective antibodies. In other instances, scientists need to use whole/dead or whole/partially incapacitated infective agent in the vaccine in order to cause an effective immune response by the recipient. In this last type of shot, there is a risk of developing a mild form of the disease targeted by the vaccine; additionally, there is a small chance of spreading the illness to another person if they are particularly vulnerable. Thus, for a very specific portion of the population -- such as those with HIV, or who are receiving chemotherapy, or whose immune systems are disable by long term use of medications like prednisone or rheumatoid arthritis drugs—there are specialized guidelines for the safe timing and type of immunizations.
Classically, vaccines are injected under the skin or deep into the muscle. But there are several alternative types that are commonly available. There is a version of influenza vaccine that is administered via nasal spray. While effectiveness varies, it increases the risk of post-vaccination respiratory irritation and is contraindicated in persons with underlying respiratory conditions. And in cholera, a disease that has ravished the third world with its lethal diarrheal illness, the most effective vaccine is administered orally. It has been shown to preferentially help the recipient develop intestinal antibodies (IgA) that are essential to efficiently vanquish this malevolent infector. Another oral vaccine though, is now no longer used in theUnited States. Oral polio vaccine, previously beloved due to its efficacy and ease of administration (just a drop in the mouth) is now contraindicated here. This is because a significant number of the new cases inAmericawere believed to be caused by exposure to recipients of this “live virus” oral polio vaccine! So inoculation protocols have reverted to the safer injection-type immunization.
Vaccines “fire up” our immune system, so it is not too shocking that they sometimes trigger a mild flu-like syndrome with aches and low grade fever afterwards. The ability of immunizations to provoke rapid and meaningful immunity is enhanced by adding nonspecific immune irritants to the vaccine mixture. These irritating substances are called “adjuvants” and are partly to blame for the discomfort associated with inoculations. Another source was thimerosal, a commonly-used mercury based preservative. However, this substance, suspected of being a causative factor in autism, has been removed from virtually all vaccinations. And though the thimerosal/autism relationship has been disproven by multiple studies, we all benefit from the reduced risk of post-vaccination discomfort. One rare, but universally feared possible immunization side effect still exists, though. That is Guillain-Barre syndrome, in which a progressive weakness, starting with the feet and moving upwards, develops. It can be brief and spontaneously resolving or it can be permanently incapacitating. Most commonly a result of bacterial or viral infection, it is felt that some case may be the result of immune stimulation by vaccination. This remains unproven, however, nor is it predictable or preventable. This is an issue still actively being researched.
Vaccines are potent medicine, and it is not surprising there may be discomfort and rarely a (hopefully mild and brief) illness afterwards. But for the majority of individuals, the benefits hugely outweigh any risks, and for the population on the whole, they are dramatically beneficial. So see your doctor, or your health department, to see what immunizations you may be due for. There is no better way to stay healthy!