Why Viruses are more harmful than Bacteria for Humans

Virus and Bacteria, both are known as harmful microorganisms that can harm our body. But virus has got a bad reputation compared to bacteria. Bacteria are sometimes good for us as they help in several functions of body, but it is not same for virus. Virus are known for some of the worst diseases that mankind has faced, such as HIV and Ebola. Virus are usually harmful and we will tell you the reason why.

What is a virus?
Virus is a protein, either DNA or RNA. It is a genetic material which needs some host cell to survive. So you can say that virus is a genetic material with no cell. Cell is known as the smallest living entity. Virus don't have a cell of their own, so they are always in need of a host cell that they can infect to multiply themselves.

Size of virus vs bacteria
Virus vary in size and they range from 17 nanometer to 1000 nanometer. One nanometer is 0.000000001 m. This size is so small that you can't see it even with a light microscope. Electron Microscope are necessary to study a virus. Size of virus is so small that they can be compared to atoms. Size of a hydrogen atom is 0.1 nanometer. Bacteria are much bigger than virus. They range from 200 to 10000 nanometer.

When were Virus discovered ?
Existence of virus was suspected near the end of nineteenth century when biologists were unable to find any bacteria responsible for some diseases/infections. They found these microorganisms much smaller than bacteria and they were unable to multiply in a solution as they were extracted out of a living body.

Virus is neither dead nor alive !
Viruses can't live on their own, so some biologists consider them as dead. They need a host body made up of living cells to let them survive. When virus enter a cell, then it replicates its proteins and infects other cells, which makes it something living. Virus is something between living and dead. It is a non-living genetic code without any cell and needs a host cell to be something living.

Are viruses more harmful than Bacteria ?
Yes, in most of the cases. Name of diseases like Ebola and AIDS can take your breath away. But there are some nasty bacteria like Neisseria meningitidis which can make you dead within a  day even after taking antibiotics. Some bacteria are equally harmful as viruses. There are lesser medicines to fight viral infections. New generations of resistant bacteria are equally harmful as we don't have any antibiotic to kill them.

Why viruses are more dangerous ?
It is because of the fact that virus can infect a cell. Both bacteria and human cell are prone to that infection. Virus is not a separate entity, as it infects by entering itself into a cell. Virus is nothing but a genetic code which disrupts the working of a cell and then starts multiplying itself. There are several good bacteria inside the human body, which can also be infected with a virus. To kill a virus we need to kill the infected cell itself which makes it more harmful for any living creature including humans.

How do our immune system fights with virus ?
Different types of white blood cells (WBC) are main part of our immune system and they can reach any part of body as they reside in the blood. Our body makes millions of them in the bone marrow every day. Macrophages (a type of WBC) destroy any germ that the detect inside the body, but virus infected cells need more advanced defense system. In order to do that more advance WBC known as T and B lymphocytes come into action. B cells make antibodies that bind themselves to virus infected cell in order to tag them and stop them from replicating. T cells act as the guard dog and informs other cells of immune system about the viral infection. Now other cells of our immune system can easily identify these tagged infected cells and kill them to destroy the virus completely. Even when a virus a destroyed some advance T and B cells creates an "acquired immunity" in our body to make our body more safe from the same virus. This acquired immunity can sometimes save our body from the same virus for complete life.

Even after all these facts about virus and bacteria, virus should be considered as more harmful. Our body has already got more bacterial cells in it than human cells. So we are more bacterial than human. But virus is something harmful to both bacteria and human cells. Virus can infect even a bacteria.