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Adaptive immunity

We are usually informed that, once we have had a certain infection, we are 'immuned' to the disease. But what exactly does it mean?

Our bodies are very very smart. Our immune system, over millions of years of evolution, have developed very specialized cells, which can be 'educated' to recognise pathogens that we have encountered before. So with each exposure to a specific pathogen, adaptive immune cells will develop into specialized memory cells, which remembers that specific pathogen. Why is this function so important?

With each exposure to a certain pathogen, the adaptive immune cells does not just remember that pathogen, it also develops cells which are very specific towards that pathogen, and it is also more efficient in eliciting an inflammatory response to get rid of that pathogen. 

Let's talk about the controversy of vaccines. It was pointed out that vaccines can cause autism in kids, but that is not the main point of this post. While I have not done enough research to comment on such claim, I think it is important we all know how vaccines work first.

Simply put, vaccines exploits this memory function of the adaptive immune cells, so it tries to 'educate' the host's immune cells (by exposure) that such an existing pathogen is bad, so that the immune cells will learn, remember and develop specific cells to target such pathogens. Also, upon encountering the real pathogenic pathogen, the adaptive immunity is able to activate the innate immune system to kill the pathogen quickly and potently. 

There aren't many documented cases of children developing autism from vaccines, while vaccines have been proven to be an effective methods in fighting widespread diseases for the long run. Maybe rethink that decision to refuse vaccination for your child?

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