Understanding routes of transmission - October 2003. Why do vaccines need to be tested in different populations?
Instead of conducting one large trial to see if an AIDS vaccine is successful, most vaccine developers plan on multiple trials of vaccines. One important reason for this strategy is that there are several different ways that people can become infected with HIV. These are called routes of transmission. An AIDS vaccine would need to protect people from infection by all possible routes. The factsheet discusses the implications of this for AIDS vaccines.
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