Are real and vaccines have been very effective against all but malaria. I'm not forcing anyone to take them but these absolutely work and we are better for having them.
If you wonder why you get sick less as an adult then you did as a kid? well half of it comes from the ones listed above. Many of these have a greater effect on children as their body does not have a coping mechanism for them yet. As you age you no longer get sick from many of these guys. This is part of the reason why kids from places with dubious water have higher incidences of childhood death but once they hit their preteen years they level off with the first world. It is also why if you visit these same regions you come down with the same diseases listed above. Add to this that as children you are in closer contact with other children all day who all have the same undeveloped immunity and for obvious reasons you got sick more often as a kid than you will as an adult.
https://en.wikipedia.org/wiki/Poliovirus
https://en.wikipedia.org/wiki/Smallpox
https://en.wikipedia.org/wiki/Measles
https://en.wikipedia.org/wiki/Mumps
https://en.wikipedia.org/wiki/Rubella
https://en.wikipedia.org/wiki/Yellow_fever
https://en.wikipedia.org/wiki/Malaria
Are real and vaccines have been very effective against all but malaria. I'm not forcing anyone to take them but these absolutely work and we are better for having them.
https://www.healthline.com/health/viral-gastroenteritis
If you wonder why you get sick less as an adult then you did as a kid? well half of it comes from the ones listed above. Many of these have a greater effect on children as their body does not have a coping mechanism for them yet. As you age you no longer get sick from many of these guys. This is part of the reason why kids from places with dubious water have higher incidences of childhood death but once they hit their preteen years they level off with the first world. It is also why if you visit these same regions you come down with the same diseases listed above. Add to this that as children you are in closer contact with other children all day who all have the same undeveloped immunity and for obvious reasons you got sick more often as a kid than you will as an adult.