The problem of new coronavirus infection is spreading around the world. Do many people realize that respiratory tract infections can cause fever and cough, and if the condition is serious, they will die? Maybe not too much. As a result, Kuhl, an active scientist and author of the free e-mail magazine Arenai Science E-mail, made a thorough evaluation of it. First of all, we explain in detail what a "pathogen" is. 

Since coronavirus is a topic, let's reconfirm what is a "pathogen"! The new coronavirus WHO has named the disease COVID-19, as a hot topic, but once again, let's sort out the knowledge about "pathogens", pathogens are the cause of the disease. Obviously, it's important to start there. there are a lot of things that are asymptomatic or unaware, such as viruses, bacteria and parasites. 

Living organisms are constantly infected by viruses, often non-pathogenic. In this world, there are all kinds of viruses, from humans to insects, plants and bacteria. It is also said to be involved in gene transfer and gene transfer, which is the driving force of evolution, even bacteria, but also bacteria, if there are no bacteria, it is intestinal bacteria and skin resident bacteria, and tiny insects called acne live in almost all humans. At first glance, a creature that appears to be a single substance is actually a symbiotic environment or medium for many organisms and viruses. 

Back to the pathogen, it is divided into pathogenic microorganisms and parasites. Some people confuse protozoa with bacteria rather than easy-to-understand parasites like tapeworms. Can we think that the virus is alive from the beginning? This is not the current agenda, so let's put it aside. Bacteria are prokaryotes, they are close to primitive life and do not have a clear nuclear membrane. On the other hand, fungi and protozoa are eukaryotes, their lives are slightly more advanced, and there is a nuclear membrane in the nucleus. 

Fungi have more atmosphere than the plants that molds and yeasts belong to, and there are more protozoa than ordinary animals, because they are more abundant than animals. (if you delve deeper into this field, it is full of refutable exceptions, so please understand that the atmosphere is like this.) suppose that human cells are 10 μ m, bacteria are about 1 μ m (some are very small, such as Rickettsia), and viruses are about 0.1 μ m, so if you have an image that seems to be reduced by 10 out of 10, protozoa are actually quite rough. So they vary according to the size of the bacteria.