Some facts: the vaccine’s safe, we need it, it works
Glenn Buchan is associate professor of immunology in the department of microbiology & immunology at the Otago School of Medical Sciences.
I AM a great believer in people’s right to their own opinion but in a generation of information overload we must be wary of those who would try to invent their own facts. It is the manipulation, or misinterpretation, of the facts to suit one’s own opinion that is the most insidious threat to public understanding.
This manipulation of the truth may be considered harmless in situations such as advertising a beauty product, but it becomes a public danger when it involves the health of the public. To this end I feel an obligation to respond to Elspeth McLean (ODT, 15.6.95). Let’s look at the facts.
“One poster screams ‘Meningococcal B can kill in 24 hours ’” . . .
This is a fact. While I am not in a position to defend the Ministry of Health’s advertising campaign, I do know from years of trying to counteract the deluge of misinformation put out by the antivaccine lobby that the harsh reality of disease, which because of mass vaccination most of us are now unfamiliar with, needs to be presented. Why sanitise it just because the anti-vaccine lobby finds it uncomfortable?
Only 184 children were proven to have MeNZB by strain-typing and of these only five died.
Ask five families per year if five deaths are not worth the effort. We have an imperfect but effective method of preventing most of these deaths; how will history judge us if we do not use it? The 184 proven or “typed” cases are acknowledged to be a gross under-estimation. In many cases, hospitals either do not have the facilities or the know-how to type all cases. The probable cases add another 158 to that figure, making a total of 342.
If five deaths isn’t enough, then contemplate the fact that around 40% (even if we only count the confirmed cases, that’s 74 children) of the survivors will have long term side effects, including limb amputation. The morbidity associated with MeNZB is more frightening than the mortality. This is despite the widespread use of antibiotics.
“There is much lumping together of all meningococcal disease . . . ”
This is not true. In fact, the figures used in the article are false. There were five children who died from the epidemic strain, two over 20 who died from MenC, and one over 20 who was classified as a probable. So, in fact, eight people died of meningococcal disease last year, of which five were proven to be MeNZB. The present programme is aimed at those who are at the highest risk first.
Only nine cases of MeNZB in Otago last year.
Disease epidemics are only stopped when the majority of a population is immune to the disease. So, if only 60% of people are vaccinated and only 75% of them are protected, this means only 45% are immune. If 100% of people are immunised, 75% are immune and this is about the level at which disease spread is stopped. That means that the majority of people must be vaccinated and those who aren’t contributing to the persistence of the disease. As the saying goes, “If you aren’t part of the solution, you are part of the problem.”
Like most Kiwis, Otago people travel a lot. They are therefore exposed to all the diseases still present in our country or in other countries. People from outside Otago constantly cross our borders. All our national vaccines are given to everyone despite differences in disease incidence from one province to another. Diseases such as diphtheria, polio and meningitis are so horrific that a simple preventative vaccine is the best medical solution we have at our disposal.
The total number of cases of meningococcal disease was down last year.
This is a fact, but taken out of context, and illustrates perfectly how one can make a plausible story by selectively using statistics. Epidemics such as the one we are facing always show fluctuations from year to year. If one looks over a number of years, the number of cases of MeNZB peaked in 1997, decreased in 1998, then peaked again in 2001, dropped a little in 2002 and 2003 and again in 2004. We do not know if this decrease will continue.
We do know from the Norwegian experience and others that these epidemics can last 30 years, which would mean New Zealand may have 14 to 15 years left to run if we don’t act now. The fact is that the best response we have is an imperfect vaccine that is expected to protect at least (and probably more than) three quarters of those vaccinated. Not to use it would be medically unethical.
What is curiously absent from consent forms . . . is mention of the link between meningococcal disease and poverty.
How many volumes will this consent form need to be? The link between poverty and most diseases is as well known as the link between lung cancer and smoking. Unfortunately, we in New Zealand are not immune to this problem. The question is what can we do about it here and now? In a perfect world, everyone would be well fed, clothed and live in healthy houses. I, for one, do not expect that to happen soon. Surely, living in such conditions is bad enough? Why should they also suffer these horrific diseases just because some have an academic concern as to the efficacy of the vaccine, or whether enough of them are dying to make it worthwhile?
“This vaccine will not work for everybody . . . ”
No-one has claimed otherwise. The scientific evidence from other studies is that protection will range from 70% to 80%. We would only know more exact figures for New Zealand by conducting a study where half the children are vaccinated and half not and then follow these children for many years to see how many from each group got the disease.
How many children would get the disease before we found out it was 70%, not 75%, and does it matter? There are a number of diseases (tetanus, diphtheria, meningococcal disease) in which the levels of antibody in the blood to the bug, after vaccination, tell us whether the person will be protected. Luckily, meningococcal disease is one of these. The safety trials have been done. The only trial not done is one to prove exactly how effective the vaccine is.
However, the studies already carried out on the first groups of children vaccinated in Auckland show that the antibody levels in children given three doses of vaccine are in the expected range. This is very good evidence that the vaccine is effective. Whether this is for four years or longer we will have to wait and see.
If there is evidence in four years that immunity is waning then another, single, dose will boost the response, just as with tetanus which we boost regularly throughout life.
With our levels of disease, most other developed countries would have begun a vaccine campaign years ago. The vaccine is safe, there is good evidence that it is inducing a protective immune response; we need it. What other questions need answering?
I am often astounded by some people’s opposition to something as positive as vaccination. I believe that the real issue that lies behind the frenzied attacks on the vaccination programme by a vocal few is a belief that vaccination is unnatural or unnecessary and that there is some great conspiracy under way to line the pockets of multinational companies. The purpose of a vaccine is to mimic infection in a safe way.
The MeNZB vaccine is just a piece of the outer skin of the bacteria. The “skin” of the New Zealand strain of MenB is just like the skins on other MenB bacteria to which vaccines have been developed, except there is a unique protein which can be used to identify it.
The process of how the vaccine is made is standard and proven to be safe. There are no live bugs and so it can’t cause infection. Every year we change the strains of flu in our vaccines to reflect the most common strains infecting people in that year. There is no scientific evidence to suspect that one killed strain is any more dangerous than another and so we don’t need to treat them as totally new vaccines.
People should know that vaccines are some of our most closely monitored medicines. All of the available, scientific evidence is that the MeNZB is a very safe vaccine.
I, too, am worried about the aftermath. It is up to all of us to remain vigilant and continue to teach our children about the dangers of all the contagious diseases to which they are exposed. My biggest fear is that, because of their efforts, the anti-vaccine lobby will be proved right. If more and more people withdraw from the programme it is only a matter of time before the numbers immunised drop too low to stop the spread of the disease. The disease will continue to kill and maim and the opponents will be able to say, “See, we told you so”.
My only question to them would be, “Will our children benefit from your pyrrhic victory?” — ODT June 29, 2005