A healthy body is your best defense against sickness. Our body is naturally equipped with antibodies that can fight off infections on its own. However, with the numerous stressors we face each day and the fact that even bacteria themselves evolve to become resistant to antibiotics.
Hence, getting yourself vaccinated is the best recourse to protecting yourself from illness and ensure you are always in great shape to do what you need to do each day. Infants and young children are required to get certain vaccinations and as we grew up, we think less and less of it unless we are asked to do so, like annual flu shots perhaps. Now, the question is, do we really need to get vaccinated or can we just rely on our natural antibodies to get us through our lifetime?
There are a number of reasons why adults need vaccines.
Vaccines wear off with time
Some vaccines given during childhood wear off with time. As a result, a booster shot(s) is needed during adulthood.
The dosing and timing varies, but an example is diphtheria and tetanus vaccines that require a booster every 10 years, even for adults.