The Best Australian Science Writing 2012 (16 page)

The original studies that supported the licensing of these drugs showed that patients with influenza who received either agent were, on average, free of symptoms about one day earlier than those who received a placebo – a real, but only modest,
benefit. Their effectiveness against serious, life-threatening influenza has never been tested by a randomised clinical trial. Each country has established a national stockpile of the drugs and these are dispensed to those most in need during a pandemic: initially, healthcare workers on the frontline of healthcare delivery.

The problem with their use as a prophylaxis is that they only work while you are taking them: if you stop the drug and are then re-exposed to influenza you can still become infected. Antiviral prophylaxis is a little akin to a World War I soldier donning a gas mask in the trenches when the mustard gas has been released: you are protected only as long as you have the mask on. To be able to safely discard the mask, to continue the metaphor, you need a ceasefire, and this can only be achieved with vaccination.

* * * * *

Flu can manifest in many ways, with symptoms ranging from trivial and short-lived muscle aches and headaches to severe muscle pain, fever, chills and uncontrollable shaking, leading to life-threatening pneumonia, organ failure and death. Every year thousands of people around the world die from what is known as seasonal influenza, with the most affected being the frail and elderly and people with pre-existing serious chronic illness. During the 1918 pandemic the sequence of completely well, to moribund, to dead could occur within 24 hours, and the disease targeted the younger and otherwise well members of the population.

We soon discovered that the 2009 swine flu was a mild disease in most people. There were exceptions: a fortnight after contracting swine flu two doctors at my hospital developed a neurological condition called Guillain-Barré, which damages the peripheral nerves and produces muscle weakness. One continued to work until he found himself unable to get out of the chair in his consulting
room; the other woke to find himself permanently unable to move many of his facial muscles.

Our hospital was busy, but because most people sick with the flu could be managed at home, there was no need for me to rush back to work and help man the pumps. A smaller number of critically ill patients required the skills of the intensive care doctors, not my humble services. My wife gave me daily updates and, while subtly mentioning the important role she was playing, made it clear that I would just be in the way. At least my dog was talking to me again.

By July it was apparent that the death rate overall was between 0.001 and 0.03 per cent of those infected, much lower than the 0.1 per cent of the 1968 pandemic. The attack rate turned out to be relatively low too, with antibody testing performed after the epidemic showing that 10–20 per cent of the population had been infected.

While some of us were busy reassuring the population that this was no 1918 Spanish flu, the intensive care doctors had witnessed something new and frightening: an epidemic of viral pneumonia that affected pregnant women, children and the middle-aged. In Australia, a total of 722 patients with H1N1 were admitted to an intensive care unit and 103 of these died, including seven pregnant women and seven children. Many more would have died if not for the heroic measures instituted in some cases – the sickest patients were treated with extra-corporeal membrane oxygenation (ECMO), the equivalent of putting someone on cardiac bypass for open-heart surgery, but instead of stopping after three hours it was continued for days or even weeks until the patient's lungs had recovered.

After the 2009 flu epidemic was over, I attended a conference where the director of a major urban ICU said that during the epidemic his unit had reached the upper limit of its ability to cope with critically ill patients. If the number of cases had been any
greater, he believed, the unit would not have been able to provide adequate care for all who needed it. If that had occurred, many older people with complications of the flu who would otherwise have received intensive care would have been denied it to allow younger people, pregnant women and other high-risk patients access to treatment.

As it was, the absence of disease in the elderly was striking. It was explained by data published in the
New England Journal of Medicine
revealing that they had gained protection through exposure to a similar H1N1 strain in the past. All good doctors read the medical literature and learn from the published work of others, but the biased view that one gains from personal experience can be very difficult to shake. Many ICU doctors were perplexed – and some were angered – by the casual approach to the epidemic displayed by some of their non-ICU colleagues, who, lacking direct exposure to the sickest patients, and despite the published evidence, promulgated the belief that swine flu was no different from seasonal influenza.

* * * * *

Criticism of the public health and medical response to the pandemic began to circulate almost as soon as the virus itself was identified. In Australia, the harshest comments were aimed at the vaccine policy. As we have seen, antigenic drift and shift allow flu viruses to evade the human immune system and new vaccines that anticipate these changes must be manufactured annually. There is no universal flu vaccine that will provide years of protection as the vaccines for polio, measles, and hepatitis B do, for example.

Every year an expert WHO panel decides what antigens the new seasonal influenza vaccine should contain. (It is probably not unfair to say that their deliberations are based on a mixture
of experience, science and necromancy.) The viruses chosen for inclusion must be inoculated into fertilised hens' eggs as part of a laborious and complicated vaccine manufacturing process. New techniques for vaccine production are on the horizon, but the current methods are essentially the same as they were 50 years ago. In a pandemic setting, most manufacturers seek government underwriting, as there are many commercial risks associated with the rapid roll-out of sufficient vaccine to cover an entire population. It takes four to five months to get a vaccine ready for distribution, by which time the epidemic may have already burnt itself out or been shown to cause only a mild illness that wouldn't justify mass vaccination.

Inevitably, there will be side effects associated with the vaccine. When tens of millions of doses are administered, even vanishingly rare adverse reactions will occur, and indemnity against claims for harm are likely to be required. Within weeks of the beginning of the 2009 pandemic, the Australian government contracted pharmaceutical manufacturer CSL to produce 21 million vaccine doses – enough for the entire Australian population. The four month lead time meant the decision had to be made when the true virulence of the virus was still unclear. It was not even known if one or two doses of vaccine would be required to produce adequate protection. To meet the unprecedented production demands, CSL had opted for multi-dose vials instead of the single-dose syringes that were usually supplied. The use of multi-dose vials has the potential for cross-contamination of blood-borne viruses and the decision was condemned by many infectious diseases experts. CSL argued that the risk of cross-infection was outweighed by the imperative of having enough vaccine ready in time. By the time it was available, in September 2009, the low death rate had become apparent and the subsequent uptake of vaccine was modest, with less than a quarter of the population opting to receive it. Millions of doses were discarded.

Australia's federal government was loudly attacked in some medical quarters for wasting tens of millions of dollars on the vaccine. And state governments were criticised for their attempts at quarantine in the early weeks of the epidemic. The WHO was accused of having over-reacted by invoking its pandemic plan and of being conflicted because of the presence of pharmaceutical and vaccine producers on some of its expert panels.

There is a well-known medical saying that things always look clearer through the retrospectoscope: what is self-evident in hindsight is hidden to us in earlier days. It is impossible to predict the course of an epidemic with any degree of precision during its earliest stages. The complexities of human behaviour, the unpredictability of the immunological response of the population and our rudimentary understanding of the basic biology of the influenza virus mean an epidemic is only truly understandable after it has occurred. If the 2009 pandemic had turned out to have the same death rate as the Hong Kong flu, Australia could have expected up to 4000 deaths; if it had mirrored the 1918 pandemic this number would have been ten or even 20 times higher.

From where we stand now it is clear that the swine flu of 2009 was a novel and serious virus but not ‘the big one'. Post hoc analyses are essential in the public health outbreak domain and you have to own up to your mistakes if you have made any. Errors are inevitable in the face of uncertainty, and in the world of infectious diseases it's hard to think of anything as unpredictable as the behaviour of the influenza virus. Had the strain been more virulent and its death rate only twice as high as it actually was, those millions of dollars now seen as wasted on unused vaccine would have been just petty cash.

Killer viruses

Emergency response

Why clever people believe in silly things

Craig Cormick

Why do so many otherwise clever people believe in paranormal events, or the benefits of fringe medicines and the dangers of infant vaccination – despite there being no real evidence to support their beliefs? According to some surveys, in Australia, about half the population believes in ESP (extra-sensory perception, such as telepathy) and one-third believes in UFOs as evidence of extraterrestrial visitation.

And a 2005 survey published in the
Medical Journal of Australia
stated that half of all Australians are using alternative medicines, and one in four are risking their health by not telling their doctor that they are doing so.

We've probably all met somebody at a party trying to convince us of the benefits of the latest alternative therapies, which is harmless enough. It becomes an issue of societal concern, however, when we see fringe beliefs, based on non-scientific values, leading to people dying from putting their trust in natural therapies or faith healing when Western medicine could have saved them.

A US National Science Foundation study found that almost nine in ten Americans agreed that there were some good ways of treating sickness that medical science did not recognise, while four in ten Americans had used alternative therapies. This is
similar to Australian data, where such beliefs are more common among well-educated upper middle-class women.

* * * * *

The issue most under the spotlight here is infant vaccination and belief in its link to autism or other nasty side effects, an erroneous belief which has persisted despite the original study by Andrew Wakefield, which linked vaccinations with autism being discredited and retracted by
The Lancet
in February 2010.

Furthermore, his co-authors withdrew support for the study's interpretations, other researchers were unable to confirm or reproduce his results, and there have since been revelations about undisclosed financial conflicts of interest on Wakefield's part.

The reasons for the persistence of this belief in vaccination being linked to autism – despite the evidence – are complex. It is very important to understand why it persists if we believe that there is a need to counter the growth in anti-science in society.

Ben Goldacre, the British doctor and author of the
Guardian
column, book and blog called
Bad Science
, coined a phrase that is crucial for us to examine: ‘Why clever people believe stupid things'.

In the US, where the anti-vaccination movement has really taken off, the Centers for Disease Control and Prevention in Atlanta, Georgia, estimates that one in five Americans believes that vaccines can cause autism, and two in five have either delayed or refused vaccines for their child.

And in Australia, according to the Australian General Practice Network, vaccination rates have been dropping over the past seven years to the point that only 83 per cent of four-yearolds nationally are covered – which is below the 90 per cent rate needed to assure community-wide disease protection and prevent outbreaks of fatal, but preventable, diseases.

In some areas, usually where there are high pockets of people choosing alternative lifestyles – such as southeast Queensland, the northern rivers of New South Wales, the Adelaide Hills and the southwest of Western Australia – vaccination rates are as low as 70 per cent.

The problem is not just that non-scientific beliefs can be very strongly ingrained in people, but that such beliefs are unlikely to ever be influenced by scientific fact.

So should we be concerned? Well only if we think that the dangers of non-science and pseudoscience are tangible and that widespread support for non-scientific beliefs can impede a society's ability to function, or compete, in an ever more complicated and science and technology-driven world.