[webmobdev]

From what I understand, it means that the vaccine is effective in teaching our immune system to successfully identify the virus / infected cells and fight it within a certain time period (which maybe anywhere between a few months to a year after vaccination - since the vaccines are new, no one is sure how long the effects last). So if you are vaccinated, and get exposed and infected by the virus, you may experience none to mild to medium symptoms (it depends on how healthy your immune system is). But the vaccine ensures that your immune system can ultimately defeat the virus and ensures the disease caused by the virus doesn't become a full blown covid case requiring hospitalisation. Note that during this period you will still be a carrier for the virus and can potentially spread it to others.

Even the current covid treatment protocol is designed to just aid your body to fight the virus successfully, and to ensure that your immune system doesn't harm you while fighting the virus (lung damage in covid cases are due to our our immune system mistakenly attacking some of our healthy cells). This is an excellent video that explains it better than me - https://youtube.com/watch?v=Bv9jDIKKUBg ...