In the previous article titled ‘Common diseases in humans – Bacterial diseases’, we examined a couple of bacterial diseases in humans. Bacterial diseases are the most common reason behind why humans get sick. The next on the list, we meet a very cunning set of organisms called the Virus.
Virus: Viral Diseases
A virus is a minute, contagious organism that replicates only when present inside the living cell of another organism. A very interesting character of viruses is that they can cause infections in all types of living being including humans, animals, and plants.When not inside a cell, virus exists as independent particles and these particles are mainly made of a genetic material such as RNA or DNA. This is why viruses have been defined to be at the edge of life.
Viruses are found almost everywhere on Earth and are the common overflowing type of biological entity. That being the case, there are quite a few troublesome diseases that we attribute to viruses like:
- Chicken Pox: It is caused by the Varicella zoster virus (VZV). Although this is not fatal anymore, thanks to the development of medicine; it is still quite serious and without adequate care, it might turn sometimes fatal. This disease results in a characteristic rash that forms small, itchy blisters all over the body which eventually are shed as sabs. It usually starts at the mid-section; around the chest and moves to the back, face and then to the rest of the body. Other symptoms might include fever, fatigue, and headache. Curiously, this disease affects adults more severely than it would to children also once you get this disease you are as good as vaccinated from another instance of chicken pox.
- Flu (Influenza): Common cold is the most common form of influenza. A disease so prevalent, it has got a prefix of common attached to it. It mainly affects the nose and the respiratory tract but not the lungs. Symptoms include a high fever, runny nose, sore throat, muscle pain, weakness, and headache. It typically lasts for three to four days. Influenza spreads around the globe every year. In the northern and southern parts, outbreaks coincide with the onset of winter whereas in the equator it could happen anytime. Over four million people around the globe are affected by 500000 deaths every year. There is no vaccine for this since the virus evolves too quickly.
Viruses break into the body cells, infect them and multiply by destroying the host tissue. Since the viruses use our own body’s tissues to reproduce, there is no reliable medicine for a virus in spite of years of research. A piece of DNA as it turns out is smarter than all the scholars in the field of medicine put together. The natural world is filled with such wonders.
Stay tuned with Byju’s to learn more about Virus and Viral Diseases.