Do vaccines work every time?

  • 1 Replies

0 Members and 1 Guest are viewing this topic.


Offline Make it Lady

  • Neilep Level Member
  • ******
  • 4050
  • Hands-on fun for everyone!
    • View Profile
Do vaccines work every time?
« on: 10/07/2008 18:53:32 »
My friend insists that vaccines don't work for everyone all the time. Has anyone been vaccinated against something and then later caught it?
Give a man a fire and he is warm for a day, set a man on fire and he is warm for the rest of his life.


Offline Evie

  • Sr. Member
  • ****
  • 200
  • "Back off man...I'm a Scientist."
    • View Profile
    • My Website
Do vaccines work every time?
« Reply #1 on: 07/08/2008 22:13:21 »
From wonderful Wikipedia (

Vaccines do not guarantee complete protection from a disease. Sometimes this is because the host's immune system simply doesn't respond adequately or at all. This may be due to a lowered immunity in general (diabetes, steroid use, HIV infection) or because the host's immune system does not have a B-cell capable of generating antibodies to that antigen.

Even if the host develops antibodies, the human immune system is not perfect and in any case the immune system might still not be able to defeat the infection.

Adjuvants are typically used to boost immune response. Adjuvants are sometimes called the dirty little secret of vaccines [3] in the scientific community, as not much is known about how adjuvants work. Most often aluminium adjuvants are used, but adjuvants like squalene are also used in some vaccines and more vaccines with squalene and phosphate adjuvants are being tested. The efficacy or performance of the vaccine is dependent on a number of factors:

the disease itself (for some diseases vaccination performs better than for other diseases)
the strain of vaccine (some vaccinations are for different strains of the disease) [4]
whether one kept to the timetable for the vaccinations (see Vaccination schedule)
some individuals are 'non-responders' to certain vaccines, meaning that they do not generate antibodies even after being vaccinated correctly
other factors such as ethnicity or genetic predisposition
When a vaccinated individual does develop the disease vaccinated against, the disease is likely to be milder than without vaccination.

I haven't personally ever caught something that I was vaccinated against, but it can happen.
"There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy."
Act I, scene 5