*A large jump in arrivals by air and urbanisation are the two main factors that are making it increasingly difficult to protect against fast-spreading diseases.

*Compounding the fears of researchers is the fact local population growth is outstripping the capacity of urban infrastructure to deal with disease outbreaks.

The study was carried out by the Centre for Complex Systems and the Marie Bashir Institute for Infectious Diseases and Biosecurity at Sydney University.

The researchers used anonymised data from the 2006, 2011 and 2016 Australian censuses to create a refined simulator which tracked households, suburbs and the movement of people.

The team of scientists studied their daily interactions to better understand how diseases spread and how to better prepare infrastructure to combat outbreaks.

“Air travel and Australians’ growing propensity to live near airports is increasing our population’s susceptibility to contagions, which has a significant impact on our health services, crisis response and pandemic preparedness,” said Professor Mikhail Prokopenko, director of the Complex Systems Research Group.

The study, which was published last week in the journal Science Advances, is the first of its kind to use anonymised census data to underpin its modelling.

“The Australian Census has provided comprehensive data with which to calibrate a nation-level model of pandemic influenza spread and investigate the population’s vulnerability to the contagion over a period of rapid urbanisation,” Prof Prokopenko said.

He and his team transformed the census data into software agents, in a powerful number crunching program known as Agent-Based Modelling which allowed researchers to tinker with the data and run different “what if scenarios.”

“So say if the Census has 20 million respondents then we have 20 million agents, each with attributes of people,” Prof Prokopenko told news.com.au.

“It is done in such a way that all the characteristics of the population such as age and travel to work patterns are maintained … It is quite sophisticated simulation.”

Deadly disease outbreaks like ebola and the zika virus have grabbed headlines in recent years but didn’t make it to Australia.

The last major pandemic to hit our shores was the H1N1 virus — commonly known as swine flu — which arrived in 2009. There were 37,500 confirmed cases in Australia, with 191 associated deaths.

According to the World Health Organisation, 18,000 people died from swine influenza around the world.

Researchers used the theoretical outbreak of such an influenza virus to test our defences. Across a number of different scenarios, they found the disease was doing more damage, more quickly.

“The peak of the epidemic happens sooner, the size of the peak goes higher and the second wave happens faster than the first wave,” Prof Prokopenko said, which is to say it spreads to rural areas quicker.

“More people get sick, sooner,” he said.

“The patterns are quite clear, which I think is why it got published,” he said of the modelling.

*It’s the combination of rapid urbanisation and the growing rate of air traffic that will make future pandemics harder to thwart in Australia.

As of 2018, 90 per cent of the total population now resides in an urban setting, concentrated in just several major urban centres across the country.

In the past decade, inbound international flights increased significantly — nearly doubling from eleven million passengers over 2006-7 to almost 20 million passengers in 2016/17.

The nature of an increasingly globalised world makes pandemics more difficult to quickly contain.

Earlier this year, Bill Gates, Microsoft co-founder and Billionaire philanthropist who works to eradicate certain diseases, warned the world could face a pandemic capable of killing 33 million people in six months.

Australia’s isolation once meant that it was spared from epidemics. “However Australia suffered from the 2009 swine flu pandemic, and has since experienced extreme seasons such as in 2017,” said Prof Prokopenko.

“I would say it’s almost inevitable that a major pandemic will strike at some point in the future.” The thing that matters is how prepared we are.

Despite an increase in medical infrastructure, many major hospitals in NSW routinely operate at one hundred per cent capacity.

8“We should be wary of the tendency for local population growth to outstrip the carrying capacity of the urban infrastructure,” Dr Cameron Zachreson from the Complex Systems Research Group said in a statement.

“We hope that our research can lend strength to the argument that keeping hospital beds at a consistent ratio to the urban population is insufficient and will not account for the relative increases in disease prevalence that our simulation results suggest will occur,” he said.

Prof Prokopenko said he would like to see Australia be “more innovative with our intervention strategies” including broader vaccination programs and protocols to shut down transport systems and schools.

“We need to develop and maintain policies that are specific to Australia,” he said.

“We cannot blindly follow what has been established elsewhere.”

SOURCE:  https://www.news.com.au/technology/science/human-body/australias-major-cities-are-increasingly-vulnerable-to-future-influenza-pandemics/news-story/1e2141eacc412a70dd759736fe41bcdd