Episode 9: Health Claims

Episode 9 – Health Claims > Conversation with Ian Frazer > Conversation with Ian Frazer

• Do you have any thoughts about what drives people who don’t want to vaccinate their children?
• Well, one very simple consideration is that if we don’t have any polio in this country—we
• don’t in Australia; we haven’t had polio in this country for many years—then why should
• my child have a vaccine to protect them against a disease which doesn’t exist in this country?
• After all, the vaccine has a very slight risk associated with it, and there is no risk of
• the disease. What people of course forget is that their children, when they grow up,
• are likely to go off to parts of the world where the infection still does exist, and
• it’s a bit late to get the vaccine after you’ve already got the infection. That’s one reason.
• It’s this, “Well, it’s not really a problem anymore.”
• In the old days, people used to rush to get vaccines. The polio vaccine was fought for
• when it first became available in the 1950s in the United States because there was an
• epidemic of polio every second year. People died. People became paralyzed. Everybody knew
• what polio was. Now the next generation of mothers and fathers don’t actually see polio
• anymore, so they don’t see a risk.
• Sure.
• There’s a second group that say, “Okay, well, if everybody else is vaccinated, I don’t need
• to get my kid vaccinated.” Of course, that’s quite correct because if there’s no way of
• the infection spreading—for example, if everybody is vaccinated against measles except
• me, I’m fine—but what they forget is that if only 99 out of every 100 people are vaccinated
• against measles, that’s still enough to allow an epidemic to occur because every one person
• that gets infected will infect potentially a hundred others. If 99 are protected, they
• won’t get it, but the other one will and will pass the infection on, so all the people who are not immunized will be at risk.
• Right.
• That’s the second reason, which is not a particularly good one, but you can understand why people
• think that, especially for infections which are not as infectious as measles. Measles
• is incredibly infectious, but most infections are not that infectious.
• The third reason why people think that is that they’ve listened to somebody who’s had
• supposedly an adverse reaction to the vaccine. They’re persuaded by their neighbors saying,
• “When my kid got it, then he had convulsions afterwards.” No, that’s a rare complication
• of measles vaccine, for example. Quite often, the febrile convulsions turn out to be occurring
• with or without the vaccine, but the story gets around: Mrs. Smith’s daughter got into
• real trouble after vaccination, and wouldn’t it be better just not to be vaccinated?
• Right.
• Those people are persuaded very rapidly when an epidemic of the infection occurs—for
• example, the whooping cough epidemics we’ve had recently—that their kids should really
• ought to be vaccinated, but it takes the infection to do it.
• Then there’s a small group of people who basically just have a set of disbeliefs about how the
• world works. They don’t believe in the infectious nature of disease, for example. They have
• an animistic approach to why people get disease. It’s punishment from God or it’s against my
• religion or whatever. They just have these fixed beliefs, and, by and large, they stay fixed.
• Yes. You’ve mentioned that one of the reasons that people tend not to immunize their children
• is, like you said, there isn’t polio in the country. If there was, well, obviously, people
• would be flocking to be vaccinated. Can you paint a picture as to what some of these things
• look like—polio and measles and so on—for people who aren’t inclined?
• Yes, measles is, in most people’s minds, dismissed as just a spotty skin disease. For many people
• who get measles, that’s all it is, but 1 in 1,000 will get a serious internal complication
• and 1 in 100,000 will be left with major brain damage as a result of measles infection, so
• that measles, if you’re the unlucky one, is not a trivial disease. In fact, more people
• die worldwide of measles than of any other infection apart from diarrheal disease. It’s
• quite a significant problem, particularly for young kids. Indeed, that’s why we push
• to get kids vaccinated as early as possible in the developing world because the risk of
• measles killing you is greatest when you’re between the ages of zero and two.
• Polio, well, for 99 people out of 100, polio is a diarrheal illness which goes away after
• a couple of days, but for 1 in 100 people, it leads to paralysis maybe of a leg or an
• arm. If you’re really unlucky, it paralyses your vocal muscles and of course the paralysis
• is permanent because the nerves that work these muscles are destroyed by the virus.
• That’s why people used to end up on respirators for the whole of their lives because they
• were basically left unable to breathe for themselves.
• Another vaccine that I’ve been involved with of course is the vaccine for cervical cancer.
• Again, the virus that causes the cancer for 98 people out of 100, it’s a trivial infection;
• they never know they’ve had it, but for the 2 percent of people who get persisting infection,
• they can go on and get a cancer which will kill them. If it’s not detected early enough,
• it’s a lethal infection. In fact, papillomavirus kills more people worldwide. Quarter of a
• million people worldwide die every year as a result of papillomavirus infection. That’s
• a very significant burden. It’s the ninth commonest cause of infectious disease death.
• Wow. One of the issues that we’re dealing with in the course is the idea of cancer clusters.
• These are quite common. We even had a case, I think, in 2006 in Brisbane. Have you had
• much experience? Do you know the phenomenon or why they tend to pop up?
• When I sat on the International Agency for Cancer Research’s Scientific Advisory Board
• for a few years, this was one of the topics that used to come up regularly. It related
• to use of mobile phones. It related to stuff being discharged from factories.
• Some cancer clusters are very real. Environmental pollutants can produce a cancer cluster. Sometimes
• those cancer clusters are the first evidence of the particular chemical that can cause
• a cancer. Minamata disease, for example, is an example where toxic pollution produced
• a whole suite of cancers, and then the Bhopal disaster as well where there was a release
• of methyl cyanate, I think it was, into the environment, and that produced a whole cluster of cancers.
• Most of the clusters that people are worried about—that mobile phone tower, this particular
• power station—there are half a dozen cancers or ten cancers in the community, and somebody
• says that’s a cluster—what they forget is that rare events occur rarely, but they do
• occur. If you’ve got a population of seven billion and you’re sensitized to looking for
• clusters, you’ll find them. You’ll find them with just the probability that you would expect
• if it’s all random. In other words, a statistical analysis plus a close look to see if it really
• is a cluster because quite commonly what you find is they say, “Well, we’ve got six cancers,”
• but it turns out that they’re all quite different and they’re not really a cluster of anything.
• They’re just six people who were unfortunate to get a disease. It’s partly statistics and
• partly common sense. You just have to remember that people do get struck by lightning every
• now and then. Cancer clusters are in the sort of struck-by-lightning or one-in-a-million chance, but it does happen.
• The title of the course is “The Science of Everyday Thinking.” Given your career, given
• your experience in vaccination and immunology and so on, what advice do you have for the
• students, the 60,000 to 80,000 students who are taking the course, to improve their everyday thinking?
• I think that basically the more educated people are, the more likely they are to make correct
• decisions about things. You can never have too much education. Even if you’re not going
• to be a scientist, if you’re not going to go out there and do experiments, understanding
• the scientific process—the fact that you can make a hypothesis, or call it a guess,
• if you like, then test it, and then at the end of the testing be reasonably confident
• about whether about whether your guess was correct or not—that is the basis for making
• decisions about things. That’s the message that I would always leave people with so that
• even if they don’t do the experiments, they should be aware that when data are gathered
• through experimentation, it is actually testing an idea and it can be falsified. You can get
• an answer that says your hypothesis was wrong.
• The alternative is straight guesswork. Don’t bother doing the experiment. Let’s just say
• I’m right, and then you get an answer. That’s not an uncommon approach to things, but it
• does lead to some very interesting mistakes.
• I think that the important thing is to say that wherever possible, test a hypothesis.
• My name is Ian. I think about infections.