Invention, mechanism & evolution of Vaccines
Vaccines are ‘miracle’ medications that have saved millions of human lives in the short history of its usage. At different stages in modern history, vaccines have addressed various diseases. For example, hundred years ago it was employed to control diphtheria in young children. Half a century back, polio was the greatest scare for children, and vaccines helped limit it’s occurrence. As a result of vaccines, most serious threats to childhood mortality and disability have been eliminated. A recent success is the eradication of smallpox in 1980. It is fair to say that vaccines have saved more human lives than any other modern medical intervention: “Viruses cause annoyances like the common cold, but they can also kill: Diphtheria, for instance, kills one tenth of those who contract it. Tetanus kills one third.” (Izakson)
Before vaccines were invented, people depended on the body’s natural immunity to fight infections. It is a time tested truth that an individual, once infected with a disease, after having recovered from it is unlikely to catch it again. This is so because during the primary infection, the immune system develops necessary counteracting components for fighting intruding micro-organisms. This system remains intact
“A small amount of a patient’s smallpox scab was rubbed into the skin of uninfected individuals, inducing a mild form of the disease followed by protective immunity. Although around 1-2 percent of variolated people contracted the disease and died, the odds were still favourable during a raging epidemic. In 1796, Edward Jenner took note of the folk observation that milkmaids had creamy complexions: they did not get smallpox. Jenner successfully used the relatively harmless cowpox as a vaccine (from the Latin vacca, “cow”) in place of smallpox.” (Weiss and Hale)
The mechanism through which vaccines operate is by activating the body’s natural defences so that it prevents infection. Not only are vaccines used by human beings but are applied to livestock and pets as well. When vaccines were first invented, their purpose was to stop the spread of infectious diseases. But today, the range of application of vaccines has grown beyond that. Ongoing research tackles prevention of non-infectious conditions such as cancer, Alzheimer’s disease or even cocaine addictions. The major future challenges to vaccine research are with relation to HIV/AIDS, tuberculosis and malaria.
While vaccines have served humanity well over the years, they are not without risks. In general, the benefits have outweighed risks by a large margin. But with major infectious diseases effectively under control today, the issue of risks associated with vaccination are being looked at again. The questions being asked are: “What if the risks aren’t simple, immediate reactions to the vaccine, like getting a light case of the illness it’s intended to prevent? What if the risks involve subtler damage to the immune or nervous system?” (Weiss and Hale) While vaccines have greatly improved the odds of human survival, risks remain: “The tetanus vaccine is known to cause severe nervous reactions in one person out of 100,000, and severe allergic reactions in one person out of each million.” (Izakson)
Some of the ingredients used to make vaccines are also being looked into, for their potential to cause health problems. Early life vaccination has been correlated to increased risk for ear infections, asthma, autism and even autoimmune disorders. But these claims have not yet been scientifically proven – they are currently mostly based on anecdotal evidence. While side-effects and unknown long-term consequences cause by vaccines are a source of objection, there are those who argue against it from a religious viewpoint. They say that preventing a bout of illness is like interfering with “God’s judgment against evil doers”. (Izakson)
At the present moment, the relevance of vaccines to modern medicine is greater than ever before. Three main factors are behind the continued importance of vaccination. First, vaccines have out-performed antibiotics as the most effective tools for fighting infections. Since bugs and microbes are developing resistance to most antibiotics, this option is proving ineffective. The second factor is that modern medicine and lifestyles have greatly increased people’s vulnerability to infections in people of all age groups and case histories, including “octogenarians, children surviving leukaemia or transplant recipients.” (Parry) Finally, “new disease is constantly emerging with novel variants of highly infectious viruses, such as flu, which have the power to completely overwhelm the healthcare system unless tamed in advance. Prevention is the pragmatic solution and only vaccination can deliver it.” (Parry)
Izakson, Orna. “Measuring Risk: Vaccines Save Lives, but Also Cause Health Problems. (Your Health).” E MagazineMay-June 2003: 40+.
Parry, Vivienne. “Treatment of Choice: With Antibiotics Becoming Less and Less Effective, There Is a Renewed Appetite to Develop Vaccines to Help Avoid the Need for Costly Cures.” New Statesman (1996)24 Jan. 2011: S4+.
Weiss, Robin A., and Peter Hale. “Vaccines Looking Back Looking Ahead.” The ScientistJune 2011: 36+.