First, everyone here should read this thoroughly. Sure, it will take a while to get through it, but you may all have a better understanding of why the use of USA stats is not a good base upon which to found a theory:http://bmj.bmjjournals.com/cgi/eletters/330/7483/112-d
It will take a while for all the responses to load as well, but you will be fired up by the end of it.
There is a major flaw in the discussion on measles. Not only is the decline "indicative" its also a flawed decline and here is why.
I am not putting in medical references for this, for two reasons. First, I haven't time to pull them all out, and secondly, pro-vaccine people should already know this stuff, and I don't see why doubters have to justify themselves.
From 1963 - 1967 USA used the killed Measles vaccine. Fortunately, it had a very low uptake. Unfortunately it was a disastrous vaccine, made with killed measles virus, which skewed the recipients immune systems, which made them more susceptible to measles after two years, but in a new form. It became called "atypical measles", which was characterized by pneumonia, high fever, atypical rash and high fatality rate. It was a "disease" which could be had not once, but repeatedly, so the vaccine was hurriedly and silently removed. Even then death on the certificate was never put down as "measles vaccine related" It was always attributed to secondary infections and malnutrition. (Which makes me want to puke but that's another story)
It was interesting to me, that they discussed something of the measles vaccine in a recent sars workshop here:http://www.hc-sc.gc.ca/hpfb-dgpsa/bg...orkshop_e.html
Back to the story. In the meantime, doctors were encouraged NOT to report measles.
When the new live vaccine was "licensed" in 1967, it was NOT used extensively. It was naturally met with some suspicion, particularly by parents who had "experienced" the joys of the first one. At first it was advised that all infants be vaccinated at approximately 12 months of age, though the routine seemed to be about 10 months. Then it was advised to be done at 6 months, particularly if there was measles around.
However, by 1979, they knew they had serious problems with this one as well, because for whatever reason, babies vaccinated at 6 months of age developed what they euphemistically called an "altered" immune response resulting in the advised booster shot at 15 months, not "taking".
Its only been in recent years that Nature published a paper showing that babies under a year of age, have hugely different immune functions and responses (which raise more questions than they "answer") than adults do, and couldn't deal with the measles vaccine given at that age. In fact, it caused immune anergy rather than an "altered" immune response. Their word was accurate, but typically they used a word which not only obscured the issue, but deflected attention from the problem.
So all these issues were swept very quietly under the carpet, and the uptake continued to be quite low. When I was in the states in 1993, I collected many articles saying that the measles vaccine uptake rate was still only around 50% nation wide. (I suspect these were perhaps understated to ramp up the rancour of those who vaccinate, against those who don't, but that's only a septic guess)
Nevertheless, because most epidemic outbreaks in the late 80's and early 90
s had 95 - 100% of cases in vaccinated children, it was seen as an opportunity to shove in a second MMR to the schedule. What a great advertisment for the first. And for the "theory" that one exposure could produce life long immunity.
The above is just a brief "attenuated" history. (Despite what Momi to baby Roni would have you believe....) The full montezuma would put everyone to sleep.
But you can see, even with this very basic information, that the statement that the measles vaccine had anything to do with the decline of measles cases is a manipulation of data, or... to put it politely... a myth.
In order to protect the unknown history of the killed vaccine, and the public's rosy view of the live vaccines, doctors were encouraged not to report measles cases where possible, simply so that parents didn't lose confidence in the vaccine.
So we got the advent of morbilli-like, or "red" measles. Anything, but not "measles".
By 1990, that the actual disease was much rarer anyway, and was simply a continuation of a trend which had been seen right up until the 80's even in the totally unvaccinated communities, such as the Amish.
2. Tetanus is a little different. Tetanospasmin, the toxin, is INCREDIBLY potent. In general, enough toxin to generate an immune response = enough to kill you. So yes, very few of us that are still breathing are immune to natural tetanus. In contrast, the toxoid in the vaccine looks almost like the natural toxin, but has no toxic effect. It can be injected at a high enough dose to generate an immune response that is cross-reactive with the natural toxin.
I have a video of a doctor who was advisor to the WHO, stating that it was well known, and many studies had been done, which showed that people do develop detectable levels of natural immunity to tetanus. I would be very surprised if a WHO doctor would lie about that.
There are also recent articles which show that people also develop high levels of natural immunity to rabies. The most recent study was done in Alaskan trappers.
But unreliable as incidence numbers may be, the fact remains that in the 1950s virtually 100% of the population had measles antibodies by adolescence (refs on request). In fact, that might partially address wasabi's query about herd immunity -- it was probably achieved relatively quickly because only the young were non-immune.
There was a very funny (funny to me, that is...) study published in BMJ years ago, but a startled doctor, who found that a select group of children tested, found that 50% of those with antibodies to measles had never had any clinical disease, and a small subgroup with rising titres also had no clinical symptoms.
This study was the first to alert me to the fact that non-symptomatic clinical measles was a common entity. Although not as spectacular as other USA studies that show that 98.8% of people with polio antibodies never exhibitted clinical symptoms once, let alone three times (you can get clinical polio again, if it is to a different "type" than you "got" before) it shows that to use antibody statistics as proof of either how dangerous or widespread a disease is, is a false argument.
Furthermore, as has been proven in Sweden, pertussis antibody maintenance is dependant upon regular exposure to the bacteria. Which is why in the USA, clinical pertussis is now becoming common amongst elderly, who had it clinically as children. Their long term immunity has been jeopardised by the interruption of the bacteria in the environment, so that they levels are no longer automatically boosted every four years, or so. Except of course, in countries like mine, where the vaccine doesn't work, and most parents take it as a bad joke.
Those graphs are not "facts". They are selectively manipulated by missing out the data from the previous 50 years. But that aside the montezuma discussion above should shed some light on why "facts" are not always facts.
I don't know why you use any information written by Otago university. I live in this country. I know the man who writes this stuff. He appeared on TV with me once, and had the gall to tell the nation that the BCG vaccine was ... well I can't remember the exact words, but something like .... "the best thing since sliced bread."
Now, here's a vaccine (BCG) that is a dead dog. That produced such BAD results in all the USA trials that USA never used it, and TB declined in USA as fast as it had in all the rest of the world where this vaccine was touted since the mid forties.
Even the best designed WHO BCG studies showed this vaccine to be useless. Unless, that is you want 50% protection against leprosy...
So please be descriminating when using sources. We in this country, know and understand this mans deliberate and willful misuse of data. pelase also note, that the USA data does go from before 1900, and this doctor deliberately and with intent, choses not to put that data in there.
You have to wonder why.
So the question that has to be asked is this.
Given that the live measles vaccine was watched carefully for a long time, how long would it have taken to achieve what the medical profession considered to be an effective herd immunity? Why do we see a sudden drop in the US data straight after 1963?
We know that with the Salk vaccine, by the end of 1958, on 36% of the target population had been vaccinated. What makes people think that in 1963, 100% of the target population had received the measles vaccine?
They can't even make enough vaccine for 40% of the target population for the Flu vaccine these days, so to make enough for 100% of the targetr population for the measles vaccine in 1963 was "pigs might fly" stuff.
Given that by 1991,a "supposedly" very high uptake of "one shot" was considered insufficient for herd immunity, what makes anyone think that the incident figures are in any way accurate for any time period after the vaccine was licenced?
USA statistics as shown in the BMJ discussions are a very bad guess at best.
Therefore it follows that any resultant postulations, based on bad guesses are as useful as the first guess.