Natural vs. "Artificial" Immunity: Which is better? Are they both natural?

There are different ways we can gain immunity to certain diseases. The two big categories of how our immune systems can obtain immunity by having antibodies present against the specific disease. Antibodies are proteins that are produced by our immune system and are what destroy pathogens (disease causing agents). They are crucial in stimulating our immune system to produce memory. There are two types of immunity which are active and passive immunity. Before I go further in depth on the differences of these two types a chart might be helpful to reference. 

https://www.healthline.com/health/acquired-immunity

 

    This is all a part of our adaptive immune system that develops over an individual's lifespan. For this we are going to focus on active immunity as this is where vaccines come into play. There are two different types of active immunity: natural and artificial. Active natural immunity refers to the individual getting sick with the disease and then producing antibodies whereas active artificial immunity(vaccine-induced immunity) refers to still getting those same antibodies, if not better, without ever getting sick. No matter what type of immunity the antibodies that are going to be produced by your immune system against the particular disease will be the same. Despite it being referred to as "artificial immunity" vaccine induced immunity is completely natural. What makes the difference between getting sick and getting vaccinated is the amount of antigen that you are exposed to. When an individual is infected with a particular disease, they are exposed to high amounts of antigens and their immune system has to work really hard to fight off the pathogen so this is why they will get sick. When an individual gets vaccinated, the immune system is exposed to small amounts of antigens where it is enough to mount an immune response to create memory but not enough to get sick. We often hear the statement, especially with Covid-19, "Well if I'm going to get antibodies either way, I'm not going to get a vaccine I'll just gain immunity from getting it". There are several reasons why vaccine-induced immunity is much better than natural immunity. Here are a few examples:

Getting sick: The best thing about vaccines is that you are able to obtain and maintain immunity to diseases without getting sick. A lot of the vaccine preventable diseases have lifelong effects on health and are not reversible. Vaccines do not cause disease instead they stimulate the immune system in a preventative sense.

https://courses.lumenlearning.com/suny-ap2/chapter/the-adaptive-immune-response-b-lymphocytes-and-antibodies/

I find this figure to be very helpful when thinking about the differences between gaining immunity from getting sick and vaccine induced immunity. The figure represents how much antibodies the immune system has at primary and secondary exposure and how strong their responses are. The primary immune response represents the immune systems first exposure to the disease and the secondary immune response represents the strong immune response when exposed to the disease again due to prior production of antibodies with memory to that disease. What is different between here is the primary immune response. In the case of gaining immunity from getting sick the primary immune response represents when the individual is sick with the disease. In the case of vaccine induced immunity, the primary immune response represents vaccination. Your immune system is doing the same thing either way and they are both natural the only difference is is getting sick or not.  

Immune response to vaccines: Especially during the Covid-19 pandemic there were a lot of complaints on how after vaccination individuals experienced flu-like symptoms for a day or two. This is actually a positive sign that the immune system is doing its job which is building immunity to the SARS-CoV-2 virus. Additionally, it is important to realize when getting these vaccines that wouldn't you rather feel fairly sick for a day or two rather than being in isolation and very sick for weeks on end? By getting vaccinated you are able you are able to not only reduce severe symptoms but also illness entirely. 

Measles: Measles is a very serious disease. If a person gets sick with measles and even if they fully recover, they will be immunocompromised for 2-3 years. Being immunocompromised means that one has a weakened immune system and they are more likely to get sick with any sort of illness. 

Tetanus: Tetanus is a very serious disease where toxins released from bacteria spread all over the body. Tetanus has a high mortality rate and recovery can range from weeks to months. Even if you survive, you gain absolutely no immunity to tetanus. The DTaP vaccine which is a combination vaccine is the only way to gain immunity to tetanus, and you don't experience the severe symptoms that tetanus brings.