As early as November 2019 Chinese officials were tracking the virus, see how it then spread across the globe.

As devastating and deadly as they were, the summer’s bushfires may have been one of the unexpected factors that helped shield Australia from the worst ravages of coronavirus.

Only finally extinguished last month, the recent bushfire season burnt 18.6 million hectares of land, destroyed thousands of buildings and claimed more than 30 lives.

At the fires’ height from September to February, images of ash falling on Sydney streets, burned koalas limping through charred undergrowth and skies turned an eerie blood red by raging blazes, were beamed around the world.

Tourist hot spots, such as the Blue Mountains, Kangaroo Island and the south coast of New South Wales, were stricken by flames with several resorts destroyed in terrifying scenes.

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Following the fires, tourism body the Australian Tourism Export Council said forward bookings from international visitors were down by 10–20 per cent as tourists were either scared off by the images or advised to rethink their travel plans.

Around 70 per cent of operators said they had received cancellations, reported the AFRat the time.

Yet, an infectious diseases expert has said this drop off in foreign visitors may have had a silver lining if it meant fewer people – potentially infected with COVID-19 – came to Australia during the peak summer season.

Australian National University’s Professor Peter Collignon told news.com.au that this, alongside other larger factors, may have played a role in slowing the spread domestically.

“I think warm weather has protected us and the bushfires may also have done so.

“A lot less people came here and went elsewhere instead. So, perversely in retrospect the bushfires may have protected us.”

There are more than 6100 confirmed COVID-19 cases in Australia with the death toll now at 53. That’s far lower than scores of other countries.

As the fires burned, the US Department of State changed its travel advisory to Australia, declaring the country was riskier than in the past, which may have deterred travellers.

During January’s Sydney Festival at least one major artist refused to travel to Australia citing the bushfires as a reason for the no-show. Other festivals and major events were cancelled.

Speaking in early February, Margy Osmond from trade body the Tourism and Transport Forum said the double whammy of the bushfires and the then unfolding coronavirus crisis was pummelling the industry.

"From an international tourism perspective, for many businesses I think this is already a crisis.

"When we're not getting any Chinese visitors virtually, that's a very substantial impact every month and for as long as this goes on, and potentially even after because we'll have to reconstitute the relationships and the marketplace,” she told the ABC.

Many virus watchers have said the single most effective measure Australia has put in place so far is limiting overseas arrivals given the majority of cases have come from people recently returned from abroad. The government instigated its first travel ban, on China, in early February.

Last year, 9.3 million tourists visited Australia of which 1.4 million were from China, according to government body Tourism Australia.

Aside from China, Australia’s top tourism markets are the US and UK, which have both had some of the world’s worst coronavirus outbreaks. Many cases here have been directly linked to people travelling from just those two nations.

Germany, France and Italy have also been hit hard by COVID-19. Substantial numbers of visitors from each head to Australia each year.

Government data on international arrivals to the country’s largest international gateway of Sydney Airport in January, the most recent figures available, show fewer overseas travellers arrived than in the same month the previous year. That reduction was modest, it also wasn’t stated where those travellers were from.

New Zealand, for instance, is one of Australia’s biggest international markets yet it has had relatively few COVID-19 cases. Large numbers of travellers from across the ditch would have had no effect on early COVID-19 cases given it didn’t register its first infection until 28 February.

But any reduction in visitor numbers from coronavirus stricken countries would have reduced the risk of it spreading further in Australia.

With international arrivals now mostly returning Australians who are being quarantined on arrival, that method of transmission is likely to cease to play a major role.

The big risk now is a rise in local community transmission and Australia’s upcoming winter season that could give the virus a boost. That could occur just as the northern hemisphere is hoping to get something of a reprieve as the weather warms.

However, Professor Collignon said the relatively low numbers of infections and deaths in Australia had given the government invaluable space to ramp up healthcare capacity. It has also allowed some analysis of what restrictions are the most effective while also creating a balance which allows people and the economy to function with some semblance of normality.

He said the most effective way to combat coronavirus going into winter was also the simplest:

“Keep you distance in crowded spaces and wash your hands, wash your hands and wash your hands again.”