The Harmless Nature of Micro-organisms

An overwhelming majority of micro-organisms are harmless and are in fact essential for life on Earth.
Micro-organisms, also known as microbes, include bacteria, viruses, fungi, and protozoans.
Many microbes live in harmony with our bodies, forming an integral part of our flora. For instance, around 500 to 1000 different types of bacteria exist in the human gut and immensely help in digestion and nutrient absorption.
Micro-organisms play a pivotal role in nutrient cycling, where elements such as carbon and nitrogen are broken down from waste and dead organisms, and returned to the environment where they can be reused by other organisms.
Some bacteria help to fix nitrogen from the air into a form that plants can utilise for growth, contributing to soil fertility.
Microbes, particularly bacteria and fungi, play a fundamental role in decomposition, helping to recycle organic materials back into their elemental forms.
Lactic-acid bacteria are employed in food production, adding distinct flavours to foods like yoghourt and cheese. Yeasts, a type of fungi, are exploited for bread making and brewing beer.
Microbes are instrumental in the development of medications, like antibiotics. For example, the antibiotic penicillin is derived from a type of fungi named Penicillium. They are also used in the production of vaccines.
On the flip side, a relatively small number of micro-organisms cause disease. These are called pathogens. The diseases they cause can be prevented and treated through various means, including vaccination and antibiotics.
Therefore, it is essential to remember that while some micro-organisms can cause harm, the majority play an indispensable role in maintaining life on Earth and providing beneficial services to humans.