Aussie flu symptoms tend to last longer than a week, doctors have warned.
The virus is spread via small droplets, made when people wth flu cough, sneeze or talk.
Britons can reduce their risk of spreading and catching the flu by washing their hands often with warm water and soap.
Further prevention methods include using tissues to trap germs when you cough and sneeze.
Maintaining good hygiene in general will lower your risk of flu infection, according to Qured GP, Dr Amy Bibby.
“Whilst you can catch flu all year-round, the illness becomes rifer in the winter,” said Bibby.
“While everyone should take the time to ensure they’ve received a flu jab, if you find yourself coming down with the flu or in contact with someone who has it, there are some important things you should know.
“You will usually be most infectious from the day your symptoms start and for a further three to seven days.
“Children and people with weaker immune systems may remain infectious for longer.”
Flu can be spread from an infected person sneezing or coughing onto a surface, which is then touched by someone else, she added.
Seeing your GP isn’t advisable, as the trip could spread the virus to other people. But, it could be a good measure if you’re over 65, are pregnant, or have a lung, heart, kidney, liver or neurological condition, said Bibby.
These patients are most at-risk of complications from Aussie flu, including pneumonia.
At least 23 people have died from flu in the UK this winter, so far.
Colds, norovirus and cold sores are the UK’s other most common winter illnesses.
Reduce your risk of catching a cold by maintaining good hand hygiene, and increasing your vitamin C intake.
Norovirus infection could be prevented by keeping contact with infected people down to an absolute minimum. Also, make sure infected surfaces are disinfected, and wash your hands thoroughly with soap and water, added the GP.
Meanwhile, cold sores are at their most infectious after they burst, but remain contagious until they completely heal. You can limit the spread by not sharing cold sore creams or medication with other people.