Boyer Lectures 2014: The Promise of Science - A Vision of Hope

ONE

SCIENCE FOR A HEALTHY PEOPLE

Try to count the number of times you might have died were it not for medical science.

Have you ever had an ear infection? I suffered terribly from these when I was a child – without antibiotics, I could have developed a deadly brain infection.

Have you had polio, tetanus, or measles vaccines? – without immunisation, any one of these diseases could have killed you.

Are you in remission after a successful course of cancer treatment?

Yes, we are extremely fortunate to be living in a time of unprecedented healthcare.

In ancient Egypt, Babylon and Greece, the average life expectancy was around 30. And life expectancy didn’t change throughout Europe for a further 25 centuries!

Today, boys born in Australia can expect to live until they are almost 80 and girls until they are 84.¹

Of course, length of life does not necessarily equate to quality of life. But it is an important indicator of the success of a society. And Australia is in the top 10 OECD countries, faring better than the UK, Canada, New Zealand and the US.

This dramatic change is thanks to medical science. How much further can it go? Can we expect – or afford – continued improvement?

I want to briefly consider where medical science has come from and where it is heading, drawing out implications not only for health but also for the economy.

Although the first medical school in Europe began in Italy in the 9th century, western medicine remained primitive, with treatments largely limited to brutal surgery (without anaesthetics!), untested herbal remedies, blood-letting and prayer.

Major improvement only started when science started moving into medicine – most notably, after Louis Pasteur and Robert Koch proved their germ theory of disease, in the late 19th century. The realisation that germs caused sickness led to the introduction of antiseptics and public health measures, including crucial education about the benefits of simple hygiene. Many, many lives were saved, especially of women in childbirth, through the simple requirement for doctors and nurses to wash their hands before and after touching a patient.

Then came the first vaccines, against smallpox by Edward Jenner, and against rabies and anthrax by Louis Pasteur.

Even with these advances, life was still precarious for children in the early 20th century – epidemics regularly stalked our communities. Tiny graves in the churchyards of small Australian country towns bear silent witness to the cruel scything by diphtheria, whooping cough, typhoid and scarlet fever. I can still remember the palpable fear when the polio epidemic hit our primary schools in the 1950s – my brother’s friend died and the girl who sat next to my sister in class was paralysed.

The first antibacterial agents, sulphonamides, did not become available until the 1930s – my grandmother told me she was one of the first patients to be treated in Australia with this wonder drug, and it saved her from a life-threatening sepsis.

During the Second World War, the toll of infections on soldiers was horrific. Australian Howard Florey and his Oxford colleague Ernst Chain set out to turn the tide. They were aware of Alexander Fleming’s early report that Penicillium mould contaminating in his petri dish had killed the Staphylococcus aureus bacteria growing there. In 1941, Florey and Chain succeeded in isolating the active ingredient, which was then mass produced in the US and shipped to the troops. Ever since, penicillin has been one of our mainstays for treating infections. It has been credited with saving 82 million lives around the world.

In today’s world, the rollout of public immunisation programs and the availability of antibiotics has totally transformed community health – smallpox has been eradicated and hopefully polio will soon be too, although there’s still a lot of work to be done to save children in developing countries from dying of diseases we now know how to avoid.

As we stand at the cusp of the 21st century, we have entered a new era of medicine, which is being driven by two intersecting scientific tidal waves: genetics and IT.

Every citizen is aware of the impact of the digital revolution – babies now play with iPhones before they can manipulate their simplest toys! However the impact of the DNA revolution is perhaps not so widely known.

DNA is the molecule of life. It’s like your hard disk, buried deep in the heart of every cell. It contains all the instructions that are necessary for your body to develop from a single fertilised egg to a fully functional adult.

The story of DNA is fascinating – it’s the story of our times. It’s also the reason I became a molecular geneticist.

I still clearly remember that day at university in the ’60s when my first-year genetics lecturer rushed into the room, words simply pouring out of him in a torrent of excitement. He had just learned of an astonishing discovery – that each of the chromosomes in our cells is composed of a single gigantic DNA molecule. Nobody had ever conceived such a huge molecule could exist. His excitement was so infectious it started my life-long love affair with DNA.

The DNA revolution had begun in 1953, when two brash young scientists, Jim Watson and Francis Crick, raced some of the most