Frank Fenner was an Australian microbiologist who died November 21, 2010 at the age of 95. He became an advisor to the World Health Organization’s smallpox erradication program in 1969. In 1977 he became its chairman. Within three years, on May 8, 1980 he announced at a World Health Assembly meeting that the disease of smallpox had been eradicated. It was the first disease ever rendered extinct in human history.
It is estimated that smallpox has been responsible for killing between three hundred million and five hundred million human beings over the course of recorded history. As late as 1967 two million people a year were dying from the disease. Of those who became infected, between thirty and thirty-five percent would die, with many of those who survived suffering serious long-term complications. For instance, it is estimated that smallpox was responsible for one third of the incidence of blindness in the world.
Up until the disease was eradicated, all children in the United States were required to get a smallpox vaccination, which usually left an odd circular scar on one’s shoulder or upper arm. It was as a result of these vaccinations all over the world that the disease was finally rendered extinct, because smallpox can only be transmitted from human being to human being. As the numbers of infected individuals lessened over the years, and the percentages of the vaccinated rose, eventually the disease had no one new to infect and simply died out. My children never had to be vaccinated for smallpox thanks to it having been eradicated; unlike my wife and I, they have no strange circular scar on their shoulders.
The eradication of smallpox is one of the greatest achievements of the twentieth century, an achievement that most people now take for granted, if they even know about it at all. It is not, however, the only disease to be eradicated. The disease known as rinderpest (also called cattle plague or steppe murrain), a viral disease of cattle, domestic buffalo, and some species of wildlife has been eradicated as of October 14, 2010. The formal announcement will be made in 2011. The disease has been a serious problem afflicting domesticated cattle for thousands of years.
Currently, there is an ongoing program attempting to eradicate the disease of poliomyelitis, better known as simply polio. The disease causes paralysis and has been a problem in all of recorded history. Today, polio remains endemic in the South Asian countries of India, Pakistan and Afghanistan and in the African country of Nigeria. A global effort to eradicate the disease began in 1988. It has been official exterminated from the Americas since 1994, China and Australia since 2000 and Europe since 2002. Currently, the number of annual cases of the disease averages around 1000. It is expected that the disease will become extinct in the very near future.
Another disease that doctors are currently working to exterminate is dracunculiasis, also known as Guinea worm disease. It is a parasitic infection caused by Dracunculus medinensis, a long, thin nematode or roundworm. Without a human host during its lifecycle, the roundworm cannot survive. It can only be transmitted from person to person by drinking contaminated water and thus can be completely prevented by getting people to either drink water that is drawn only from underground sources free of contamination or by simply filter their drinking water by using a fine mesh filter made of nylon or other cloth. Additionally, those infected need to be kept from entering ponds or wells that are used for drinking water. Water sources can also be treated with poisons to kill off the worm-carrying crustaceans. Thus, this disease can be eliminated without vaccination. People merely need to slightly change their behavior.
At this time, the disease still exists in Sudan, Ghana, Mali and Ethiopia. Sudan suffers the worst. It is responsible for 86 per cent of all the world’s cases, but the ongoing civil war there has made the process of eradicating the disease very difficult. Nevertheless, as with the ongoing attempt to eradicate polio, health workers remain optimistic that this disease will soon be known only to history.
Five other infectious diseases have been identified as eradicable with our current medical technology: measles, mumps, rubella, lymphatic filariasis and pork tapeworm. Lymphatic filariasis and pork tapeworm are parasitic diseases. Measles, mumps and rubella are virus infections and like smallpox can only transmitted from person to person. They can be easily prevented by vaccination. As more and more people are vaccinated, the chances for infection will continue to decline and ultimately those diseases will cease to exist. Those who refuse vaccination are therefore delaying the extermination of these diseases and endangering the health of those around them.