People should think about influenza the way they thought about COVID-19 and, as winter approaches, her advice is “don’t let your guard down”.
The official government message is that this year it is even more important to get a flu jab, as the population is more vulnerable to infection because of low exposure during the pandemic and lower uptake of flu vaccines in 2021.
In an average year, Professor Jenkins says, flu kills between 800 and 1000 Australians and makes thousands more severely ill. When deaths from pneumonia and other respiratory viruses are added to flu, the number soars beyond 4000.
“Many people who previously suffered true flu report it as being significantly worse than an infection with COVID-19,” she says.
Even the common cold can outlast COVID-19. A large study conducted recently by King’s College, London, found that symptoms of omicron in people with a booster jab lasted half as long as a cold.
With three jabs, omicron symptoms lasted an average of 4.4 days. Cold symptoms tended to last seven to 10 days.
This winter will be unique because flu will co-exist with COVID-19. While it is rare to become infected with both simultaneously, some suggest this has not happened much because flu has been at historically low levels.
A double infection would be serious for high-risk individuals and the elderly.
It is possible, however, to get one virus after another. Whether one makes a person vulnerable to the other is unproven, but remains a theoretical possibility.
Closed borders, social distancing, masks and sanitizing kept flu mostly at bay during 2020 and 2021, and limited other respiratory viruses.
“Now, borders are open, behaviors have changed and Australia is back to pre-pandemic times, and pre-pandemic relaxation about respiratory viruses,” says Professor Jenkins.
The latest data from Flutracking.net shows respiratory illnesses in Australia are back up to pre-pandemic levels for the autumn months.
It is going to be hard for people to know if they have a respiratory virus, COVID-19 or a rhinovirus that causes common colds.
Talk of a ‘super-cold’
There is new talk in Australia about a “super-cold” that masquerades as COVID-19. This was reported in Britain in November when people emerged from lockdown into winter.
Some suggest it may be the result of first encounters between new viruses and the immune system after isolation. There is no evidence yet, and it may just be that people have forgotten what it is like to have a bad cold.
“We’ll probably see a return of the number of deaths, and the burden on hospitals, that previously occurred through the winter months as a result of respiratory illness and pneumonia,” says Professor Jenkins.
“Even though hospitals have been bearing the brunt of COVID-19, they haven’t had anything like the usual prevalence of pneumonia cases that will undoubtedly tick up significantly. And there will be pressure on primary care too.
“We can protect ourselves, to some extent, with flu vaccinations, and personal precautions, particularly by wearing masks more frequently when we’re out, at least until late August, early September.”
By April 6, Australia had recorded 598 notifications of laboratory-confirmed influenza for the year, according to the National Notifiable Disease Surveillance System.
Although flu has been rewoken, the consequences of its long absence are unknown. A drift in an influenza strain that has not been seen before could be an important determinant of a bad flu season.
“If we don’t learn from the pandemic about the value of wearing masks, minimizing social activities with symptomatic people and keeping up vaccinations, we may be in for a nasty shock this winter,” Professor Jenkins says.