'Brisbane' flu virus sees cases spike
A less severe strain of the influenza virus known as the B ‘Brisbane’ virus is a contributing factor to a recent spike in Queensland’s high number of notified influenza (flu) cases.
Executive Director of the Communicable Diseases Unit, Dr Sonya Bennett said the Brisbane strain was not covered by the government subsidised trivalent flu vaccine, but was included in the privately available quadrivalent vaccine.
"The World Health Organisation sets the annual flu vaccine composition based on what strains are prevalent in the northern hemisphere at the time," Dr Bennett said.
"There are often two types of B flu strain in circulation during the flu season, with one strain usually predominating and no way of predicting which strain that would be from year to year.
"Circulating influenza virus strains can vary from year to year, and it is not uncommon for a spike in figures to occur with the appearance of a strain not covered by the current vaccine."
Dr Bennett said it was important to note that influenza B strains were less severe than influenza A.
"While both types circulate each season, the proportion attributable to influenza B is variable, with influenza A infections generally predominant," she said.
"That’s why the vaccine composition covers two strains of A, and one of B.
"Being vaccinated gives you the single best protection against flu by building immunity to the virus and preventing transmission of the virus to other people."
Dr Bennett said emergency departments had been busy this year with people presenting with the flu and other respiratory viruses, but this was "business as usual" for flu season.
"It is difficult to predict when the flu season will be over but figures suggest we are nearing or have reached the peak.
"The flu vaccine takes up to two weeks to be effective but it may not be too late to protect yourself and we would recommend this specifically for people who are in high risk groups for severe illness.
"While Queensland does have amongst the highest number of notified flu cases in Australia, this is not unusual.
"A similar pattern is being seen along the east coast of Australia.
"Our excellent testing and reporting mechanisms may contribute to the fact that that our numbers are often higher when compared with other jurisdictions.
Tips to prevent the spread of flu:
- Talk to your doctor about being vaccinated.
- Avoid close contact with people who are sick.
- When you are sick, keep your distance from others; stay at home from work, school and avoid other crowded areas.
- Wash hands frequently, using soap and water for at least 20 seconds.
- Cover your mouth and nose with a tissue when coughing or sneezing. Dispose of used tissues in a bin and wash your hands immediately afterwards.