Vaccination is one of medicine’s great success stories, preventing deaths and serious ill health caused by infectious diseases – and almost always doing so without causing serious harm in the process. I will be discussing the lives saved and harm prevented by vaccination against diseases such as pertussis and measles in this post, but first a note on safety. As Rümke and Visser wrote: “During recent years a scala of diseases or symptoms have been associated with vaccination (presumed side effects). Careful and extensive investigations have shown that such hypotheses could not be supported. […] The total number of cases where at least a possible relation between side effects and vaccination is observed–apart from local reactions and moderate general symptoms–is very rare (about 0.25 per 1000 vaccinations) and does not balance the benefits from vaccination.” Not everyone accepts that vaccination is safe and effective. Sadly, some of these people mislead others into thinking that vaccination is less effective or more dangerous than it actually is.
Here, the Vaccination Council has an article about herd immunity. It’s written by Suzanne Humphries MD. It’s pretty awful. This is the concluding paragraph:
I believe that when diseases disappear from sight, the disappearance is never solely by virtue of the vaccine. Yet the vaccine always gets the credit, because the blind faith in vaccines is prioritized over the scientific evidence. Evidence to the contrary of the value of vaccination is consistently snuffed out and kept away from the mainstream media, so that the herd never hears a peep of the truth. Instead, they get the “herd immunity” sound bite, which gives undeserved credit to the risk-benefit ratio of vaccination. Inside the web of half-truths and misinformation, the vaccine religion somehow justifies the public display of resentment and fear of the unvaccinated.
It is ironic that the author complains of half-truths and misinformation, and the prioritisation of blind faith over scientific evidence. The line about “evidence to the contrary of the value of vaccination” being kept away from the mainstream media isn’t even a half-truth – it’s simply untrue. Any suggestion of harm caused by vaccination or ineffectiveness of a vaccine, no matter how weak or unreliable, is likely to make headlines. It is the evidence of efficacy and safety that is ignored by the mainstream media.
Let’s look at the parts of the article that deal with pertussis and measles.
Pertussis is now hot news and the unvaccinated interrupting herd immunity is raised over and over, despite the science that shows the vaccinated are by far and away the most affected by whooping cough.
“Our unvaccinated and under-vaccinated population did not appear to contribute significantly to the increased rate of clinical pertussis. Surprisingly, the highest incidence of disease was among previously vaccinated children in the eight to twelve year age group.” 
This is the most recent, but not the first study to demonstrate 86% of cases of proven whooping cough are in the vaccinated. How can getting even 100% vaccination uptake create an immune herd with such vaccines?
Now, it’s true that the unvaccinated aren’t entirely to blame for outbreaks of pertussis (although they’re certainly a factor). Immunity from vaccination (or infection with pertussis) fades over time and those who have been vaccinated against the disease might no longer be protected 5 or 10 years later.
It’s also true that some research has shown that 86% of cases were in those vaccinated against pertussis. But does that prove that “the vaccinated are by far and away the most affected by whooping cough”? No. That single statistic does not tell us whether those who are unvaccinated suffer milder or more severe symptoms than the vaccinated. Nor does it tell us whether the unvaccinated are more or less likely to be infected with pertussis (without knowing the figures for vaccine coverage as well as the figure for the proportions of those with whooping cough who are vaccinated or unvaccinated, we can’t tell).
Let’s take a look at some numbers. Vaccine coverage in England & Wales is 96%. Say there were roughly 60 million people in England and Wales. That would leave us with 57.6m vaccinated and 2.4m unvaccinated. Say there’s 10000 cases of pertussis and 86% are in the vaccinated (8600) and 14% in the unvaccinated (1400). That’s 1400/2.4m in the unvaccinated population and 8600/57.6m in the vaccinated population. That’s 0.000149 cases per vaccinated person and 0.000583 cases per unvaccinated person. (15 per 100,000 versus 58 per 100,000.)
I reckon that means you’re about 4 times more likely to have whooping cough if you’re unvaccinated. You can change the figures for population and number of cases and the figures for risk will be unchanged. Only changing the figures for vaccine coverage or cases of pertussis will affect the figures – in America the population is over 300 million and the figure for vaccine coverage is slightly higher at around 98%, which would (if 86% of cases were in those vaccinated) mean you would be 8 times more likely to get whooping cough if you’re unvaccinated.
That pertussis vaccination isn’t perfect (because of waning immunity) doesn’t mean you’re better off unvaccinated. Quite the contrary. If 86% of cases are in the vaccinated and vaccine coverage is >86% (as it has been in this country since 1990/91 – HPA) then that just shows that you’re less likely to get whooping cough if you’re vaccinated against it. So, if you’re less likely to get pertussis if you’ve been vaccinated against it then having the vaccine would seem to be a good idea. I’m not sure that’s the conclusion the author would like us to reach.
…and that’s just covering the issue of whether or not you get whooping cough. I’ve not even addressed the question of whether your symptoms (if you had the vaccine) will be more or less severe than the unvaccinated. Neither did the author of that article on the Vaccination Council website.
So how can they claim that “the vaccinated are by far and away the most affected by whooping cough”? What’s the basis for that claim? A single percentage figure with no context? Apparently so.
That most cases of pertussis are in those who have been vaccinated does raise an important issue – that of waning immunity. The answer to the problem of waning immunity in those vaccinated against pertussis isn’t to throw your hands up and say “well, vaccination’s useless then and herd immunity is a pipe dream” (apart from anything else, not all vaccines have this problem of fading immunity). Some sensible solutions have been proposed. In California, 7th grade students are required to have a booster. See also the BBC report here: http://www.bbc.co.uk/news/health-18747527
So far in 2012 there’ve been 2,398 cases of the bacterial infection in the UK, compared with just 272 in the same period last year.
Why have cases of whooping cough shot up? No-one is sure why; better testing and increased surveillance explain part but not all of the rise.
The Joint Committee on Vaccination and Immunisation – whose recommendations apply across the UK – has been considering how to deal with the resurgence of whooping cough.
One option is a booster dose in adolescence. Adam Finn, a professor of paediatrics at the University of Bristol, agrees that a new strategy is required.
He told me: “Giving a booster to adolescents is one thing that might help, but other things being considered are immunising parents of newborn babies, pregnant women or health care workers.”
There are basically three options – not to vaccinate against pertussis, to continue the current vaccination programme, or to add a booster. Personally, I don’t think much of the first option. We tried it once before in this country.
Here is what happened when there was an ill-founded scare surrounding the pertussis vaccine: “…immunisation coverage [dropped] to 30% in 1975 resulting in major epidemics in 1977/79 and 1981/83. As a result, there were more than 200,000 extra notifications and 100 deaths in 1970s and 1980s.”
From 1978 to 1982 there were 44 deaths from pertussis. By comparison, there were 11 deaths in the first five years of the 1990s and 15 deaths in the years 2000-2004. Because, despite the problem of fading immunity, pertussis vaccination still saves lives. [Source: HPA PDF.] The complications of pertussis include pneumonia (5.2% of cases), and seizures (0.8% of cases). 20% of cases are serious enough to require hospitalisation. There is a 1 in 500 chance of dying from the infection. [Source: CDC PDF.]
And onto measles…
“Measles is mildest when the infected person is replete with vitamins C and A. The devastation and mortality you hear about with measles comes from starving populations. “
Measles has a mortality rate of 1 in 2,500-5000 in developed countries. There were 87,000 notifications of measles between 1992 and 2008 in England & Wales, and 24 deaths (PDF: HPA – Measles notifications and deaths in England and Wales, 1940-2008). That’s one death for every ~3600 notifications. According to the CDC, approximately 30% of reported measles cases have one or more complications. Complications include diarrhea (8% of cases), otitis media (7%), pneumonia (6%), seizures (0.6-0.7%) and encephalitis (0.1%). [Source: CDC PDF.] Not all the devastation and mortality you hear about with measles comes from starving populations.
“Talk to your grandmother about measles. Ask her if she saw death and destruction from the disease. It was not a disease that needed eradication. The high death rates were in countries where children were undernourished and lacked vitamins necessary to process the virus.”
Never mind talking to your grandmother. She might or might not have seen deaths from measles. Her personal experience might not be representative. Look at the figures on deaths from measles in the HPA PDF I link to above. In 1968, we got the first measles vaccine in this country. Oh, look at that. Prior to 1968 there were hundreds (even thousands) of deaths from measles in every decade. 85 deaths per year in the 60s (up to 1968 when the vaccine was introduced). 140 per year in the 50s (almost exactly a hundred times as many deaths per year as there were in the period 1992-2008, I might add) and 570 per year in the 40s. Other countries, with “starving populations”, might have had higher death rates but people were still dying and getting seriously ill from measles infection in this country when vaccination was introduced (and elsewhere – in the United States, measles caused 450 reported deaths and 4,000 cases of encephalitis annually before measles vaccine became available in the mid-1960s).
The number of deaths from measles decreased before the introduction of the vaccine (as anti-vaccinationists will never tire of telling us) but there were still 85 deaths per year at the time it was introduced. There were only 32 deaths per year from 1968-75 with vaccine coverage around 45% and 16 a year from 1976-85 with vaccine coverage around 60%. From 1992-2008 vaccine coverage was around 90% and there were on average just 1.4 deaths per year from measles. In this country, thousands of lives have been saved since the introduction of the measles vaccine. In America, it’s probably tens of thousands of lives saved.
If you don’t think that those were lives worth saving, then perhaps it wasn’t a disease that needed eradication. If you don’t think that protecting people from the non-fatal (but still serious) consequences was worthwhile then perhaps it wasn’t a disease that needed eradication. If you aren’t bothered by people suffering ill health or dying from a preventable disease then, sure, that’s a perfectly valid point of view. It seems a little callous to me, though. How much misery and death need a disease cause before it can be said to need to be eradicated?
“The vaccine was created because it could be done, not because we needed it. Measles is not eradicated. Outbreaks happen all over the world, and will continue. And now infants will be unprotected because of the absence of maternal antibodies in their vaccinated mother’s milk. So much for protecting the most vulnerable in the herd. “
No, the vaccine was created because people were still getting sick and dying due to measles infection. And measles immunity in babies due to transfer of maternal antibodies wanes rapidly whether the mother is naturally immune or vaccinated. (See also this in the BMJ.) So children still need to be vaccinated, because protection from maternal antibodies wears off within 6 months. And whether they’re protected by maternal antibodies from a naturally immune or vaccinated mother they will still be relying on herd immunity during the period between the protection from maternal antibodies wearing off and being vaccinated. (For children who receive the MMR vaccine at around 12 months of age and whose mothers are naturally immune, that’s from 2-4 months of age up until vaccination – or 8 to 10 months; for children whose mothers are immune from vaccination, that’s from 1 month to vaccination – 11 months.) So, contrary to the article by Suzanne Humphries MD, childhood vaccination and herd immunity are both important for infants whether their mother was vaccinated or had natural immunity. That immunity from maternal antibodies fades is no more than an argument in favour of timely immunisation. It’s also worth remembering that in obtaining natural immunity you run the risk of dying from the complications of measles.
Infants today (like those in Duisburg) are unprotected not because of vaccinated mothers but because we don’t have rates of vaccine coverage high enough for herd immunity. Because anti-vaccinationists bullshit about measles not being a dangerous disease, about immunity conferred by maternal antibodies, and about the effectiveness of vaccination.
Update, 11th August 2012
Homeopath Steve Scrutton has written a blog post that has some discussion of pertussis and vaccination. It includes this:
“Following several Tweets that have arisen from the recent Whooping Cough epidemics in the USA, it has become clear that the Pertussin vaccine is just not working. Worse still, for denialists, is the growing evidence that vaccinated children fare worse than the unvaccinated, and that the vaccinated who get the disease get it far worse.”
Scrutton does not provide any evidence for his assertions that vaccinated children fare worse than the unvaccinated and suffer worse symptoms. This is ironic, given his complaints in the same blog post that skeptics do not provide evidence.
I’ve noted in the above blog post about the Vaccination Council article that those who are vaccinated are less likely to contract pertussis than those who are unvaccinated. (And Scrutton might find the attack rates given in this paper interesting: link. Or those given here.) Let’s have a look at Scrutton’s unsubstantiated claim that “the vaccinated who get the disease get it far worse”.
“The illness can be milder (less severe) and the typical “whoop” absent in children, teens, and adults who have been vaccinated with a pertussis vaccine.”
The CDC page links to this: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1177947/
“Clinical picture of pertussis in previously immunized children is usually characterized by such classical symptoms as prolonged and paroxysmal cough, rarely by whopping and post-tussive vomiting, and very rarely by apnea. […]
Tozzi et al.  in a study of 788 laboratory confirmed cases of pertussis had demonstrated that the duration of cough in vaccinated children was about one month, while in unvaccinated was two times longer.
Unvaccinated children more frequently presented the full spectrum of classical pertussis symptoms than vaccinated children. German study  has shown that 90.2% of unvaccinated patients (mean age 4.3 years) had paroxysmal cough, 78.9% whooping and 53.3% post-tussive vomiting. The frequency of paroxysmal cough in fully vaccinated children (median age 11 years) in our study was similar (84.4%), but post-tussive vomiting and whooping was more rare (accordingly 31.3% and 28.2%). Only one 11 years old patient had apnea.”
I don’t know what evidence Steve Scrutton has, as he fails to cite it. I do know that the evidence I have seen, which I have linked to above, contradicts Scrutton’s statements on vaccination and pertussis.