How bacteria, viruses and germs differ

With the Coronavirus being a major topic of discussion, there are many people who do not know the difference between bacteria, viruses and germs and Polokwane Observer recently discussed the topic with John Dunlevey, a former Professor in the Department of Biodiversity at the University of Limpopo.
“Life is complicated, and tiny life-forms are very complicated. However, with the present pandemic everybody is concerned with these. So let us make sure we are all talking about the same things and using the same language. Although some specialists have reservations about the exact classification of certain life forms let’s go with the generally accepted meanings,” Dunlevey advises.
According to Dunlevey, a germ is a very widely used term to describe a life form that has a negative effect on one’s health. “This includes any living thing such as a bacteria, virus, spore or even parasite egg that can in any way damage human health. The instruction “Wash your hands after you have been to the toilet” is a classic example of getting rid of all these ‘germs’.
Bacteria are single-celled organisms with a distinct structure that can be crudely described as a cell wall, the protoplasm and the nucleus. Bacteria abound everywhere from the deepest depth of the ocean to the upper atmosphere and photosynthetic ocean bacteria produce significant quantities of the oxygen we breathe. However, just as there are bacteria that like plants adsorb energy from sunlight and use chemicals to grow and reproduce; there are others that eat bacteria or other cells. The ‘bad’ bacteria to humans are the ones that feed on our cells – skin, stomach, gut or lung linings, as this causes health problems we refer to as being sick or ill. The ‘good’ bacteria that help us digest food and eat ‘bad’ bacteria we do not think about,” Dunlevey explains.
Viruses are generally smaller and less complicated than bacteria,. Viruses require a host to replicate and most attack bacteria. A virus can be regarded as an extremely complicated chemical. It penetrates a cell and uses the contents of the cell to create replicas of itself, which of course destroys the cell, according to Dunlevey.
“So if you get ‘bad’ bacteria or ‘bad’ viruses and your immune system cannot fight them off, the cells in your body get destroyed and you have problems. Antibiotics help against bacterial, but have little effect on viruses as a virus is only active after it has penetrated a cell and by then it is too late.
In terms of life-span both bacteria and viruses vary greatly. Bacteria usually have a short life span, but some can go into a dormant state and survive for many years. Viruses are more like very, very complex chemicals that only slowly break down, but are more susceptible to adverse conditions,” he says.
“So where does this leave us with the corona virus? Well, it has to get into your body to make you sick. Your skin is a very good defence, but your mouth and eyes are the weak points. So wash your hands to remove any virus.
“There is no perfect manner to avoid infection, but taking simple precautions and understanding what is happening are the first and most important lines of defence,” he reckons.

Story: BARRY VILJOEN
>>barryv.observer@gmail.com