I got to thinking about how vaccine dosage goes for delayed kids who are much larger than the recommended age for a particular vaccine OR for vaccines that are given at intervals throughout development.
Who knows about how this is determined?
Great chart, Rrrrachael. Thanks for that! It's hard for me to get my head around that the dosage is the same for an infant and and adult. What are your thoughts on that?
It depends. E.g. HiB and Prevnar, if given after a certain time (15 and 18 months I think) only need one dose. Measles induced sufficient titers in 95% of all vaccinated people. So I would run a titer test instead of revaccinating.
Others technically require a basic 3 injection round to establish some immunity (DTaP, IPV, HepB) - but if you are like me and only interested in the T portion, if started after age 2, 2 shots usually induce high tetanus titers. After 2 years of age the child's immune system is quite mature and doesn't need a gazillion doses of repeated vaccines. I'm a big fan of titer tests - drawing blood hurts for a split second, lab personnel is quite nice and it's quick. No harm done in taking a little blood!
As to same dosage: it doesn't make sense to me. A child receives a lot more antigens/weight than an adult would. I know it is often justified with kids need more antigen in a vaccine to evoke sufficient antibody response. I never do flu shots but I think I read, and correct me if I'm wrong, if given at 6 and 7 months, they only give them half a vial each time.
I decided I wanted to see a bit more action on this subject so I posed another thread in D&D. http://www.mothering.com/community/t/1374518/help-me-understand-vaccine-dosage