Sunday, January 20, 2013

Herd Immunity

This is good

2 comments:

George Henderson said...

Except that the vaccine may not work for Bob. But even a vaccine that only works for half the people immunized would effectively stop the spread of some diseases.
It is more mathematical than this example suggests, herd immunity could protect a vaccinated person whose vaccine did not take.

George Henderson said...

A downside of vaccination would be as follows; there is no effective vaccine for HIV or HCV, so a great deal is known about the natural history of these viruses and increasingly effective treatments are available.
There is an effective vaccine for HBV; less is known about its natural history and there is no really effective treatment. Despite the fact that HBV was identified long before HIV or HCV.
Vaccine successes tend to create blind spots in which treatment languishes.