When bird flu killed six people in Hong Kong in 1997, virologist Robert Webster was quickly on the scene.
On the upside, the Balclutha-born virologist has done the swabbing in all sorts of exotic locations. Over the past 50 years, he’s tested for the influenza virus in samples taken from birds on the Great Barrier Reef in Australia and the Guano Islands in Peru; in the Florida Keys and Delaware Bay in the US; and in China, Hong Kong, Siberia and Antarctica.
It’s made for a virology career with a difference for Webster, who has just published a memoir called Flu Hunter: Unlocking the Secrets of a Virus.
“Most virologists spend their time in laboratories rather than chasing viruses around the world,” says Webster from his home in Memphis, Tennessee, where he has lived since the 1970s.
Webster’s many decades as a flu hunter haven’t just provided him with great travel opportunities. They’ve also established him as a leading flu researcher who helped prove that flu viruses are spread by wild aquatic birds to domestic poultry and pigs, and eventually to humans.
“Wild aquatic birds are the ultimate reservoir for the influenza virus – all the families of influenza viruses that we know about live in the wild ducks of the world.”
He describes ducks as the Trojan horse of the flu virus. They rarely show any signs of the disease but can spread flu viruses long distances, and infect birds and animals such as poultry and pigs. Occasionally, thanks to a process Webster calls “reassortment”, avian and animal flu viruses can exchange genes with human flu viruses to create new flu strains people have no ability to fight.
By the 1990s, it was widely accepted that influenza could emerge in poultry and pigs from viruses in wild aquatic birds. But it was still not accepted that bird viruses could lead directly to influenza in humans.
That all changed in 1997, when six people in Hong Kong died from a strain of flu called H5N1 that had previously appeared only in birds. Webster immediately flew to Hong Kong and, after testing for H5N1 in local poultry, he and his colleagues recommended killing the country’s 1.5 million chickens to stop the virus – known as bird flu – from spreading.
Webster’s big fear was that the H5N1 virus would either reassort or mutate and develop the ability to spread easily from one human to another – with potentially catastrophic results. Although only a few people are susceptible to the H5N1 virus in its current form, it has a much higher mortality rate than the Spanish flu of 1918, which killed 50 to 100 million people.
Fortunately, although the virus still exists in many parts of Asia, it has not yet developed the ability to spread between humans. But Webster says it still could. This may happen through the process of reassortment, most likely in a pig that has been infected simultaneously by the H5N1 virus and a human flu virus. Or it could simply mutate. He suspects mutation – possibly caused by the mustard gas used in the trenches during World War I – is what turned the Spanish flu from a relatively benign virus into a killer.
H5N1 is just one of several existing flu viruses with the potential to cause serious pandemics. Others include H7N9, another bird flu that has occasionally spread to and killed humans, and H2N2, which has been lurking in the world’s wild birds since it killed 1.5 million people in 1957.
Webster, who at age 86 continues to keep a close eye on the latest flu research, says these threats make efforts to find both a cure for the flu and a vaccine to prevent it even more urgent.
“Sooner or later we’ll have a nasty one so let’s prepare for that with drugs and universal vaccines and so on. We’re certainly a lot better prepared than we were in 1918, but we also have air travel, which could spread it to every part of the world in two days.”
Flu Hunter: Unlocking the Secrets of a Virus, by Robert G Webster, Otago University Press, $35
This article was first published in the September 22, 2018 issue of the New Zealand Listener.