Eradicating Disease: Smallpox vs. Malaria

As I continue to do research, I'm finding more information both in support of, and in opposition to, the use of scientific means to treat/"cure" illness. The following two case studies I found interesting. They land on both sides of the issue.

Check it out:
In 1958 the Soviet Union went before WHO (the World Health Organization) and asked for international support in eliminating smallpox. Historically, smallpox has been a particularly vicious killer. It wiped out a quarter of the Roman population around 165 AD and ravaged multiple people groups throughout history (during the British colonization of the Americas, smallpox infested blankets and clothing were given to Native Americans, essentially wiping out the AmerIndian population at several points on the map). By 1958, smallpox killed roughly 2 million a year and was a serious issue in at least 33 countries. Although a vaccine had been discovered (a similar strain of smallpox, known as cowpox, had been in use for years and had a success rate of 99%) smallpox was still a major problem worldwide, and especially in Russia, Africa and Asia. Needless to say, the campaign to eradicate smallpox won international support almost immediately and worldwide vaccinations were put into effect beginning in 1960. Vaccination would reach points of 250 million a year, and teams of researchers travelled the world, seeking out those who had not been vaccinnated, mapping and treating outbreaks, and keeping tabs on varying strains of the smallpox virus. For the next 17 years these travelling researchers would devote their lives to eradicating this disease.
22 years after eradication was proposed, on May 8, 1980, WHO announced the world to be free of smallpox. Now, it is no longer a problem. It has literally been wiped off the face of the planet. (Yes, if you follow the news, there have been some questions raised recently about whether or not smallpox still exists, and if it were to be released upon the planet, yes, there would be a worldwide plague in which essentially a quarter (or more) of the population would die. But, barring this speculation, smallpox is a threat of the past-- one of the greatest acheivements in the history of the war against microbes.)

However.
On the flip side of the issue, around the same time as the campaign against smallpox, WHO also launched a campaign against malaria. The discovery of DDT (see below post) gave hope for the complete elimination of the Anopheles mosquito. Basically, DDT was an insecticide that rested in environments for years after the initial spraying. It had no effect on humans, but would kill certain insects who came in contact with it.
The year 1958 ushered in a worldwide campaign to eliminate malaria, and DDT spraying began simultaneously all over the globe, with at least $23.3 million a year in support from the US Congress. Dr. Paul Russell, a malariologist at Harvard at the time, led the campaign. He was adamant about the speed with which this process must be carried out. Failure to eliminate mosquitos in the proper time period could result in biological resistance to DDT and other insecticides. That could postpone the eradication of malaria indefinitely.
Because of the strict timeline, Congress agreed to fund the campaign through 1963, which was the proposed date for which malaria would essentially have been destroyed.
Needless to say, it didn't work out. By 1963, Russell was close to complete elimination of the disease. In some parts of the world (such as Sri Lanka, who had experienced 1 million cases a year previously and in 1963 had only 18. One eight.) were already celebrating Russell's success. However, he needed only a couple more years of funding to complete his mission. Congress, however, viewed Russell's gains as failure, and proceeded with their plan to withdraw funding. Without this essential chunk of the budget, DDT spraying halted, and little could be done for the fight against malaria. By the time Russell regained enough money to continue the campaign, DDT-resistant mosquitos had begun to emerge. Without additional forms of insecticide, they spread rapidly and took over, increasing the number of cases in places that had been nearly (if not completely) clear just two years earlier. Soon, malaria became even more prevalent, and cases more virulent, than they had been at any point in history. It is considered one of the biggest failures in scientific history.

Machupo, Bolivian Hemorrhagic Fever

I've begun independently studying some fields of interest; for the moment, that means infectious disease. This first case study totally blows my mind. I've been thinking quite a bit lately about the best way to fight illness/infection. Machupo virus is a good example of what happens when humans mess too much with science...

Here is what happened: around 1962, an epidemic broke out in eastern Bolivia that they called "Hemorrhagic Fever". Microscopic holes in the veins and capillaries of the body allowed blood to drain into the tissues, preventing proper blood flow to major organs, sending the body into shock. Electrolytes and liquids in the body became imbalanced; clear cerebrospinal fluid became tainted with blood; the eyes and skin would fill up with blood, and the patient would eventually die. The virus caused intense pain, and had a 50% death rate, an almost Roman decimation, which was incredibly dangerous to the population and the researchers themselves.
NIH dispatched a team of three scientists to study the outbreak, and after a year or so of research, they found that the disease (Machupo, or Bolivian Hemorrhagic Fever) was carried in a certain type of field mouse, known as the Calomys mouse. These mice had literally overrun small towns in Bolivia, especially San Joaquin, in the past decade or so. Their ecosystem had been upset by the agricultural push from the natives, as they cleared fields for harvesting crops, the mice were forced to move elsewhere and provided with an easy source of food. They invaded the towns and feasted on leftover bits of food, nesting in the homes.
The virus was passed from the mice to the humans by way of urination. The mice urinated almost pure samples of the Machupo virus, which was highly contagious and became airborne, infecting the humans who shared their environment. They could pass it on to their families by physical contact OR the families could also become infected via mouse piss.
However, for the first several years of the agricultural boom (which began in 1952), no epidemic occurred. The mouse population was kept at bay by domestic cats who prevented them from entering homes and contaminating them.
The outbreak did not occur until around 1962. This year the government began dusting villages with DDT in an attempt to kill off the Anopheles mosquito population, essentially halting malaria. But the DDT residue (which was so thick in places that it looked like a coating of white flour had fallen over everything) had the unfortunate effect of killing off the entire domestic cat population in San Joaquin.
Rather than treat hemorrhagic fever with medicinal elements, the team of researchers brought in several hundred cats, and provided the town with a steady supply of mouse traps. It literally stopped the disease cold.

If it weren't for the use of DDT in the first place, the epidemic might not have ever started. If the mouse had not been removed from its natural habitat or provided with fast access to unlimited food resources, virtually without predators, the population would not have expanded so rapidly or contaminated humans.
Just a little something to think about... although I do like the fact that, in this case study, they sought to eradicate the illness by restoring the original predator/prey relationship... rather than by introducing a new predator (a chemical "solution") and further distorting the natural flow of things.

ANYWAY. I'm exhausted. I just wanted to talk about that a little before I went to bed, because I knew I would probably lose the ability to explain it tomorrow. I wish I knew someone who liked to discuss these things. =(