Remember the flu?

An astonishingly low number of influenza cases have been recorded in the past 12 months. From the start of the year to the beginning of May, there were 240 notifications to the National Notifiable Diseases Surveillance System in Australia. 

Roughly at the same time last year, there had been over 20,000 cases. Meanwhile, COVID-19 landed in Australia. The country’s borders were shut and lockdowns were put in place. We were asked to physical distance, wash our hands and wear masks. Flu notifications plateaued, reaching just over 21,000 by the end of 2020. 

By May 2019, influenza cases in Australia were over 44,000.

“There is a combination of elements that have contributed,” says Associate Professor Holly Seale, an infectious disease social scientist at the University of New South Wales. “Enhanced social distancing, people being more aware of their hygiene, wearing masks, fewer people coming in from abroad – all of that would definitely have contributed to lower levels of flu.”

The influenza virus circulates globally. Seasonal flu viruses emerge and evolve every year in the tropical belt, particularly in East or Southeast Asia. People carry flu from place to place, transmitted from person to person through coughs, sneezes and breathing. In the northern and southern hemispheres, the flu arrives with winter.

Keeping our borders shut has protected us from significant outbreaks of the influenza virus. But low levels of seasonal flu don’t mean flu vaccines are unnecessary.

“It is somewhat still early…to make any real assumptions about what’s going to happen. We can’t become complacent,” Seale says.

“Annual vaccination is the most important measure to prevent influenza and its complications,” advises ATAGI, the Australian Technical Advisory Group on Immunisation.

But according to FluTracking, data have revealed a sharp decline in influenza vaccination rates. Notably, only about 56% of healthcare workers have received a flu shot so far compared with over 88% last year. In addition, about 20% fewer people over 65 years of age have received a flu vaccine this year. 

As winter approaches, experts urge the community not to forget their flu shot – the influenza virus kills hundreds of Australians every year. “Influenza is still going to be around. That is why we are still encouraging people to get the flu vaccine as well as their COVID-19 vaccine,” says Seale.

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