In microbiology, a distinction is made between three types of potential #ziekteverwekkers : bacteria, viruses and parasites.BacteriaBacteria are unicellular microorganisms without a nucleus. They occur almost everywhere and therefore in the human body. In fact, in your body there are more bacteria than you have on your own body cells. A large part of it does meaningful work and is crucial for your metabolism and defenses. All harmless bacteria together are also called the “microbiota”.
There are also bacteria that cause diseases such as diarrhea, respiratory infections, or meningitis. This is done in different ways, for example by excreting toxins or suppressing the immune response of the host.

Diseases caused by bacteria can usually be combated with antibiotics. Such agents aim to kill bacteria in your body and focus on specific species (narrow-spectrum antibiotics) or, conversely, on the elimination of a large number of families (broad-spectrum antibiotics).VirusesViruses are inanimate infectious microparticles, which can cause all kinds of diseases. Unlike bacteria, their multiplication depends on a living host cell. Once intruded, they use the host cell's machinery to multiply themselves. After that, new virus particles are released, which again infect new host cells. There are viruses of all kinds and sizes. They are therefore classified into families, such as herpes, corona and retroviruses. Some of them cause only mild illnesses; think of a runny nose, a cold sore or a mild flu.

But there are also serious ailments caused by viruses, for example, HIV, SARS and Ebola. For some virus infections, treatments are available, aimed at healing or suppressing the course of the infection. There are also virus infections against which there is no cure yet.

A viral infection can not be treated with antibiotics: a virus does not live, and therefore can not be killed. Therefore, antiviral drugs are usually aimed at disrupting the reproduction of the virus. Another way to prevent virus infection is vaccination: with it, the body learns to recognize and fight specific viruses. The own immune system is ultimately best capable of eliminating viral infections.ParasitesA parasite is an organism that lives together with another organism. He uses the host to stay alive and multiply himself. Although this relationship is at the expense of the host, the damage is usually not so great that the host will suffer. If that is the case, you speak of a parasitoid. But also parasites can cause unpleasant ailments. In humans, they occur in the form of worms, fleas, lice and ticks. The most famous disease caused by a parasite is malaria.

A parasitic infection, is treated with a parasite killer. Most of them focus on limiting the production of proteins by the parasite. Without those proteins, the parasite can't grow and die.
It's that multiplication that puts a lot of people on the wrong foot. The spread of a virus is always exponential in nature, a world that is completely unknown to many people. From that world come terms such as exponential growth, growth factor and doubling time. Rest assured, you do not need to be a mathematician to get an idea at such terminology. A simple illustration is enough for an aha-erlebnis.

Imagine a pond with one water lily in it and imagine that it reproduces itself every day. Offspring go through the same process. On what day is the pond half full of water lilies? Keep this question in mind when watching this video:






Bacteria, Viruses and Parasites