One of the interesting effects of the measures brought in to contain COVID-19 is that there were far fewer flu cases in Queensland in 2020 and 2021 compared with previous years.
Queensland Health’s data shows that over the five years from 2015-2019 there was an average of more than 38,000 lab-confirmed cases of flu a year.
There were just over 6,000 cases notified in 2020, and only 296 in 2021—a very dramatic drop.
A range of public health measures were put in place in 2020 and 2021 to limit the transmission of COVID-19 infection. These included lockdowns, closure of domestic and international borders, reductions in large gatherings, social distancing, hand hygiene, and wearing face masks. These measures helped prevent COVID-19 cases, as well as flu cases.
The importance of getting the flu vaccine
If there’s not much flu around, why bother getting vaccinated?
There are several very good reasons.
Flu has not gone away completely. With restrictions easing and borders reopening, we could face a significant flu season in 2022. Complications from flu can be lethal, so it’s important to get a flu jab every year.
There is also the chance that you could get COVID-19 and the flu at the same time, particularly if you have not been vaccinated against one or both.
Importantly, getting vaccinated against the flu helps protect vulnerable people who cannot get vaccinated, such as infants and people with weakened immune systems.
About flu
Influenza is a respiratory illness commonly known as ‘the flu’. Typical flu symptoms include fever, cough, muscle aches and pains, nasal congestion, headache, sore throat and fatigue.
While most people recover from the flu in about a week, sometimes the flu can lead to other serious health problems like bronchitis or pneumonia or make a person’s existing health problems worse.
Complications from the flu can be deadly: on average the flu causes an estimated 3,500 deaths in Australia each year.
Influenza is caused by a virus, which is a tiny infectious germ that hosts itself in another living organism’s cells. Influenza viruses are classified into different types and sub-types. Influenza A and B are responsible for most of the illness in humans.
Different strains dominate each year. Some strains may be more severe in certain age groups. For example, the dominant strain in 2017 was H3N2 and this had a greater impact on older age groups.
Influenza viruses can evolve and mutate allowing new strains to emerge, against which people may not have immunity.
The best protection against flu is to be vaccinated against it
The flu is highly contagious, spreading when an infected person coughs or sneezes. Droplets containing the influenza virus also settle onto surfaces, such as telephones and doorknobs, and can then pass from hands to the nose, mouth or eyes. People with influenza can be infectious to others from 24 hours before they display symptoms until a week after the start of symptoms.
It’s recommended that all Australians over six months of age get a flu vaccine each year.
They should have the vaccine for two reasons:
To stop themselves from getting ill.
To limit the spread of the virus to others in the community, particularly those most vulnerable to infection.
In Australia, the vaccine is provided for free for children aged 6 months to less than five years; people aged 65 years and over; pregnant women; Aboriginal and Torres Strait Islander children from six months upwards and adults; and people with certain medical conditions which increase the risk of complications from influenza.
It’s important to get a flu shot every year as the circulating virus strains change. Receiving the vaccine from April allows protection from the flu to develop well ahead of the peak transmission period, which usually falls around July and August.
How the flu vaccine is made
In February and September each year, the World Health Organization (WHO) holds a conference with leading experts and influenza centres from around the world to make recommendations about the composition of the next season’s flu vaccine.
They look at all the current information about influenza, including the recent patterns of flu epidemics across the world, to decide which strains of flu are likely to be most common in the next flu season. Vaccines are created to protect against these strains, usually containing three or four strain vaccines.
For countries in the Southern Hemisphere, like Australia, the information from the September conference helps them plan for flu vaccines for the following winter. After the conference, the Australian Influenza Vaccine Committee meet with the Therapeutic Goods Administration to confirm which strains will be included in the Australian flu vaccines. The vaccine funded for the National Immunisation Program in Australia contains the two strains of Influenza A most commonly circulating and the two Influenza B strains.
These vaccines then need to be manufactured. It’s a long and time-consuming process.
Please see the 2022 influenza vaccination guidelines (Queensland) for details about the strains which are targeted in this year’s vaccines.
Flu and COVID-19
Both the flu virus and the virus that causes COVID-19 are circulating this year, with symptoms that can be similar. Refer to Symptoms of COVID-19 compared with flu, common cold and allergies for more information.
Always stay at home if you have any symptoms at all.
The Australian Technical Advisory Group on Immunisation (ATAGI) now advises that COVID-19 vaccines can be co-administered (given on the same day) with an influenza vaccine.