Advertisements tell you that bacteria and viruses are all over your home, you need to buy antibacterial products. And the question is, should you? So, I want you to think about it, we’ll discuss it in the end.

In this, we’ll be talking about the overview of immune system. Today you are going to learn about the facts of immune system and immunity. How does it work in our body? The first thing and the easiest way to think about immunity is. Let’s say your body is a country. It has its defense system having cops or any detectives. It will find out the culprits, which are growing there and destroying the country. Once they find they will be put in prison or ultimately sentenced to death. So that is the idea of the immune system because you know our body has to monitor and keep all the organs and themselves healthy.

Why do we have to think about it in the first place because we have invaders, foreign materials entering our body which are dangerous and try to compromise the body’s system? They invade the body cells, destroy the organs and make us sick. Our body can’t survive in that mode. So, the body will protest against the invaders. The body is prepared to fight against those invaders called pathogens. This immune system is fighting against those pathogens and keeping us safe. So, this is the generalized view of the concept of immunity.

The study of the immune system of an organism and how it protects the body from physical, chemical, and biological invasions is called immunology. So the immunology studies how a pathogen such as bacteria or virus invades a living organism such as a person’s body and how the body reacts to it.

The human body contains specialized organs or structures which work together with other parts of the body to control and destroy these pathogens. These special organs are the thymus, lymph node, spleen, and bone marrow where special immune cells are produced. They’re all connected in some way and referred to as the organs of the lymphatic system. These organs will try to destroy the pathogen but you may think doesn’t the body contain good bacteria, isn’t the body full of bacteria even, and does that mean the body constantly attacks itself. Well, it’s interesting to know that the human body does contain more bacteria than cells in a given area anywhere. So how does the body live with these bacteria, well it turns out whenever we heard bacteria it’s referred to as something bad, but the human body needs bacteria to live such as the gut microbiome which is vital in the digestion of food. From this, we can say there are good bacteria and bad bacteria. In better words self and non-self-pathogens. The body recognizes its micro biome and this is why you hear an unsuccessful organ transplant because the new organ is a foreign substance, a non-self-substance will initiate an immune response triggering an attack on that new foreign organ. The body can also attack itself called autoimmune disease. This happens when the immune cells recognize their organs as a foreign system. You might have heard of an autoimmune disease affecting joints such as rheumatoid arthritis.

The immune system can be divided into innate immunity and adaptive immunity also knows as acquired immunity. Innate immunity is a quick response against the pathogen and it’s a first line of defense. The adaptive immunity is a delayed response and is an antigen specific response. It is a second line of defense.

First let us look at the innate immunity, innate means inborn, which means its present at birth. Innate immunity can further divide into physical barrier and physiological barrier.

Physical barrier includes, skin which is made of multiple layers, Hairs prevents harmful organisms from contacting skin, and secretions such as sebaceous and sweat glands especially tears contains mucus, enzymes, stomach acids, lysosomes and antibodies protects from infections.

Physiological barriers have key players within it which are mainly, macrophages, dendritic cells, phagocytes having mast cells and other granulocytes complementary proteins which help destroy a pathogen and allergens. These cells are connected with t-cells which then initiates the adaptive immune system.

The cells of the adaptive immune system are the b-cell which secrets antibodies and the t-cells. The t-cells then can differentiate into t-killer cells and t-helper cells and all these cells are connected in some way. Let’s quickly look at what antibodies means. Antibodies are y shaped looking things which are able to bind to antigens. When these antibodies are successfully produced and are able to bind to pathogens, the immune cells such as phagocytes can then easily eliminate the pathogen.

Because the main players of the adaptive immune system are the b and t cells, the adaptive immunity can further divided into humoral and cell mediated immunity where the b cells are the main players of the humoral immunity and the t cells are the main players of the cell-mediated immunity. But essentially the t and b cells and cells of innate immunity phagocytes and antigen presenting cells have to work together to destroy pathogen.

Let’s understand how exactly immunity works in the body. When the pathogen decides to invade a body and goes from the outside to the inside, the innate immunity kicks in, first the phagocytes will consume and destroy the pathogen, when it fails the antigen presenting cells such as macrophage or dendritic cells will present the antigens of the pathogen to t-cells. Then t-cells will be able to differentiate into t-killer cells which will destroy the pathogen and t-helper cells which will in turn activates b-cells to secrete antibodies. Antibodies destroys the pathogen.

Now, a very important concept is that the human body can create memory from the first exposure of certain disease. For example if someone got flu it might take some time to recover but the second time they get that same flu they recover much quicker and this is due to the memory cells. These memory cells from the adaptive immunity produces antibodies on second exposure and get rid of disease.

And this conclude the overview of the immunology. Coming back to the question which I asked in the beginning, what you think? Should you use the antibiotic products for daily cleaning or not?

The overuse of antibacterial cleaning products, including disinfectants in the home, maybe produces strains of bacteria that are resistant to multiple antibiotics. Bacteria that are resistant to many antibiotics are known as multi-resistant organisms (MROs).

As a marketing strategy, media advertisements suggest that bacteria in the home are harmful and must be eliminated by using any number of antibacterial or antimicrobial products available.

These cleaning products are no more effective at preventing infection in the home than good personal and household hygiene using ordinary soap, warm water, and plain detergent.

Avoid using antibacterial or antimicrobial products unless you have a specific medical reason to do so.

Most bacteria help humans. For example, intestinal bacteria help us to digest food. The ‘good’ bacteria that naturally live on and inside our bodies help us stay healthy by keeping the numbers of ‘bad’, disease-causing bacteria under control.

When you use antibacterial or antimicrobial cleaning products, good bacteria are also killed. This could be harmful if the ratio of good to bad bacteria is disturbed, and bad bacteria get the upper hand.

Researchers have suggested that the modern obsession with cleanliness may be partly responsible for the increase in allergies.

It has also been suggested that some exposure to certain microbes may help regulate the immune system. This exposure may reduce the body’s tendency to develop an allergic reaction against common allergens.

This is based on the observations that growing up in a large family, being in child care from a young age, and living with household pets seem to reduce the chances of developing allergic diseases.

More research into this area is needed, but current understanding seems to suggest that the immune systems of children may need some exposure to bacteria and other microbes to function at their best.

In other words, a little dirt never hurt anyone. We should target our hygiene practices to the areas of greatest risk, such as washing hands after going to the toilet and before handling food.