The “theory” of herd immunity does not apply to a vaccinated population. It was conceived based on observations of measles outbreaks in non-vaccinated populations in the United States during the 1930s and how those communities, as a whole, were protected from becoming infected after about 55% (or slightly more) of the people came down with the disease and developed “natural immunity” to it.
There can be no such thing as herd immunity in vaccinated populations because vaccines do not confer immunity. You know, the kind that lasts a lifetime. The real immunity. Not this temporary stuff that requires people to keep getting these silly “booster shots” forever and ever. And even then they never achieve immunity, just a lot of shots.
Amazingly, in some measles outbreaks, 20 to 40 percent of the people infected had been fully vaccinated with two doses of the MMR vaccine. Don’t believe me? Check out the study by Gregory A. Poland, MD and Robert M. Jacobson, MD titled “The Re-Emergence of Measles in Developed Countries: Time to Develop the Next-Generation Measles Vaccines?” published in the journal Vaccine on January 5, 2012. They call it “primary vaccine failure.” Nice.
Even worse, though, is the fact that in the current measles outbreak in the US, for example, some, if not many, of the children who have been diagnosed with measles actually got the measles virus from the MMR vaccine itself. They call it “vaccine strain” measles and, unless you test everyone who has come down with measles, there is no way to know for sure how many of those cases are vaccine strain measles and how many are “wild-type” measles.
They’re not testing widely. There is no mass surveillance system of this kind in place, So it is possible, even likely, that a large percentage of the measles cases being reported have occurred as a direct result of MMR vaccinations. I suspect no one at the CDC is too keen on knowing how many of cases of vaccine strain measles there are out there. Imagine the kind of damper that would put on their efforts to encourage people to get vaccinated and get their kids vaccinated.
So, not only do people who have been vaccinated with the MMR vaccine not provide herd immunity for the population as whole, they have actually placed themselves at risk for contracting measles by the very thing they believed was going to protect them. One hell of a bubble I just burst for you, huh?