There is absolutely no doubts that the earth is blessed with an enormous diversity of both plant and animal species. Out of these, man has found foods, raw materials for different products as well as medicines in case of ill-health. Nature has such a beautiful organizational structure if you understand what I mean.
If the documented history of man is anything to be taken seriously, it is known that the early man survived through hunting of smaller animals and gathering of fruits in the forest, covering his nakedness with leaves in an era of very little or no technology. Food in itself is a medicine. However, several plants and animals, including their products were utilized in the treatment of different ailments. In short, biodiversity has been a source of life to man.
In those days of treating illnesses with herbs from various plants, there were no basis for measuring doses. Hence, a lot of deaths and ineffectiveness recorded might have been due to cases of overdose or under-dose of the active or biological components of the herbs. However, with advancement in technology comes the capacity of man to extract some of the medicinally important components of herbs and formulate them in pre-determined doses in form of oral tablets and capsules, suppositories, pessaries as well as intravenous infusions. For example, quinine which is widely used in the treatment of malaria is a chemical substance first isolated from the bark of the South American cinchona tree, Cinchona pubescens.
Today, wide classes of drugs exist in various pharmacies, chemists, and shops around which are used in the treatment of different ailments. While some are classified as an analgesic for pain related treatments, some are classified as antihistamine for treatment of allergies, some as antifungal for treatment of fungi related infections while some are classified as antibiotics for treating bacterial related diseases.
When it comes to illnesses or diseases, classification is done based on certain features. One of such features is the transmissibility of the disease. Diseases that cannot be transferred from one person to another are usually termed non-transmissible diseases or non-pathogenic diseases while those that can easily be transferred from one person to another through various means are called transmissible or pathogenic diseases. The pathogenic diseases are caused by biological organisms otherwise known as pathogens. The pathogens of man include bacteria, viruses, fungi, nematodes, Platyhelminthes, protozoans etc.
It is somehow safe for a layman to assume that as man increases in knowledge to advance technologies and live more sophisticated lifestyles, so are the pathogens of man and other animals. It will not be totally out of place because over the years, the drugs that will normally work in the treatment of certain pathogenic diseases have increasingly lost their potencies. To a layman, this trend can be largely attributed to the increasing sophisticated lifestyles of pathogens. After all, they are also animals like us.
However, the increasing ineffectiveness of drugs in the treatment of pathogenic diseases have been scientifically linked to the development of resistant genes within the genomes of pathogens. The resistance has been opined to be brought about as a result of natural selection. How does this happen?
According to Darwin, the leading proponent of the natural selection theory, the environment always favour organisms that are well adapted and as such, they produce more offspring which are also well adapted to the same environment. Organisms that are not well adapted eventually die or phase out of the population, leaving only the strong ones. The genetic diversity of a population always ensures that the entire individuals within the population are not susceptible to the same effects, treatments or diseases. Hence, a drug taken to fight a particular pathogen does not entirely wipe out all the populations of the pathogens within the body system. The few surviving ones eventually re-establish themselves and produce more offspring that are genetically immune to the effects of the same drug. A good example if the evolution of methicillin resistant Staphyloccocus aureus and vancomycin resistant Escherichia coli.
Aside from the problem of resistance, the unusually expensive prices of conventional drugs and accessibility is a major challenge in some developing and underdeveloped countries. For example, 1g Augmentin which is a wide spectrum antibiotics of amoxicillin/clavulanic acid mixture goes for as high as five thousand Nigerian naira (approximately $17) and might even take a considerable time before one can get it around certain areas in Nigeria. Hence people are left with very little option than to fall on alternative medicines in form of herbal concoctions and other forms.
Like I was telling a colleague this morning, I am of the opinion that all plants are medicinal. The medicinal uses of some have been discovered through ethno botanical and cultural use, some are still being researched while a whole lots are still left unexploited. As of today, over four hundred thousand species of plants have been identified out of which few have been exploited for medicinal benefits. It is estimated that over a million species of plants are yet to be identified, let alone exploited for medicinal use.
The health and general well-being of future generations of man is going to be largely dependent on the identification and discovering the uses of some of the plant and animal biodiversity. As a Botanist working in a Microbiology Department; I have been, and still researching on the potential medicinal benefits that some of the identified plant species in the tropical area could offer us. One of such researches which I am currently working on would be shared in my next article.
Till then, stay steeming!
References
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