Microorganisms - Knowing our enemies and keeping our friends close.
When placed in context of the actual number of microorganisms in existence, those that cause disease in humans are relatively minimal. In fact, the majority of microbes are of great benefit to humanity, even in providing therapeutic interventions to treat and prevent diseases that are caused by other microbes.
With respects to Microbiology, what the twentieth century has revealed is the need to continue to expand on the existing knowledge of microbes, with the objective of harnessing the potential of those that are of benefit, and creating the environment in which those that are of detriment to human life can no longer thrive.
At the beginning of the 20th century, diseases due to microbe infection were the leading cause of death throughout the world, yet life as we know it today has seen infectious diseases to a large extent quarantined to the poorest regions on the globe. Apart from the advancement of pharmaceutical intervention in disease treatment and prevention, what has actually been the major catalyst for the shifting from infectious diseases to "lifestyle diseases" (e.g. cancers and heart disease) as the leading cause of death, is an improvement in the quality of life of people living in regions now referred to as the developed world. This improvement ranges from better housing and water sanitation, the ability to earn higher incomes per household, and the ability to develop a greater understanding of the body's nutritional requirements along with access to high quality food sources. Yet what has also drastically improved the developed world's response to infectious disease is greater understanding of the life cycles of microbial agents, which has seen their impact on health and mortality reduced to a substantial minimum in many parts of the world.
A clear-cut example of utilizing the potential of microbes is the rising demand for sustainable bio-fuel production. The use of butanol as a petrol substitute, tipped to surpass its predecessor ethanol due to its potential to store more energy, has long been known to be produced by the bacteria Clostridium acetobutylicum via sugar fermentation. This process has since been optimized and has seen major investments by the biotechnology industry, with the intention of significantly up-scaling butanol production within the next few years. This method of bio-fuel production can also assist in removing the edge off the alternative energy industry, which has recently been bombarded with critique as being a major contributing factor to the rise in global food prices, with land used for food production being designated to growing biofuel crops.
Infectious agents vary considerably in their habitat and mode of transmission, which can range from food or water borne, insect vectors, human to human, or animal reservoirs. Each agent in their respective mode of transmission has the potential to reach epidemic proportions, provided appropriate and effective prevention strategies are not put in place.
An example of a dangerous microbe is the Plasmodium parasite, which causes malaria. Malaria is a vector-borne disease caused by the protozoan parasite, of which four species exists that cause disease in humans - P. Falciparum, P. Vivax, P. Ovale and P.malariae
Malaria, an ancient disease that has more or less been eliminated from the developed world; despite it being less widespread today, actually claim the lives of more people than it did thirty years ago. This has largely been attributed to an increase in drug resistance and mass poverty combined with an inadequate health infrastructure, particularly in tropical countries where malaria is endemic.
Knowledge of the pathogenesis of the Plasmodium parasite and its life cycle within human liver cells has been and will continue to be essential to providing effective treatment such as Quinine, Chloroquine, SP, Melfoquine, Artemisinin, and the eventual vaccine, while knowledge of the mosquito vector will provide further insight into malaria prevention strategies such as reducing breeding sites, larvicidals, and bed nets.
In light of the successes the past century has witnessed, there is still tremendous room for growth and improvement in the field of Microbiology, which is why this avenue of research is currently one of the most important disciplines for the collective survival of humankind.