'Australian flu': It's not from Australia

We are speaking Italian each time we say "influenza."

It's the "influence" of the stars on human beings that causes the sickness, according to Italian folklore from centuries past.
Influenza entered the English vocabulary in 1703, when J. Hugger of the University of Edinburgh used the word to describe the flu in a medical thesis.
Much more is known today about what actually causes influenza, but the contagious respiratory illness remains an international health threat.
Currently, flu is widespread across much of the world, including most of Europe, Asia and North America. In particular, the United States is having what Dr. Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases, calls a "bad year" of flu.
Fauci said the most common viruses circulating this season are two A group viruses, H3N2 and H1N1, and some B viruses.
H3N2 is the virus making most people sick, he said; it was also the dominant strain in the Australian season and the reason why many people refer to "Australian flu." Though the strain did not originate in Australia -- one study suggests that it emerged in or near Hong Kong -- it quickly became dominant during the Australian flu season of 2017 and has gone on to dominate the world's infections.
"When H3N2 dominates, it generally is a bad actor from the beginning and usually foreshadows a bad year," Fauci said. "Superimpose upon that the fact that it is likely that the vaccine is not going to be particularly effective this year."
Meanwhile, as global headlines scream warnings of a deadly "Australian flu," experts say the current season is not unexpected.
"This year is more on the severe end, but this is what you should expect from seasonal flu," said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota in the US. The current season may be of epidemic proportions, but it is certainly not a pandemic, he said.
A pandemic is what happens when a new influenza virus emerges and spreads across a large region -- or even around the world.
The term epidemic describes what happens when the number of people affected by an illness rises above what is normally expected. Seasonal flu outbreaks -- which move quickly and leap borders -- are caused by viruses that have already circulated through the population.
And this is what is happening during the current season.
First stop: Australia
Australia is sometimes viewed as a harbinger of what's to come, because this Southern Hemisphere country goes through its flu season at the same time Northern Hemisphere countries are enjoying some summer sun. (Seasonal flu is associated with the colder fall and winter months, which come to the Northern Hemisphere later.)
Though experts hold a finger to the Australian pulse, they do not take for granted that a similar flu season will hit the Northern Hemisphere. This season, some of the Northern Hemisphere is following Australia's lead.