Annual report card rates flu vaccine as ‘moderately’ effective

Flu monitoring continues year round.
Image: Fightflu

by Anne Crawford

This year’s flu season in Australia might be winding down but for researchers investigating and monitoring the highly contagious and potentially deadly disease, work continues year-round.

Monash University researchers Professor Allen Cheng, from the Department of Epidemiology and Preventive Medicine and the Respiratory Medicine Laboratory’s Associate Professor Tom Kotsimbos, are part of FluCAN (the Influenza Complications Alert Network), a sentinel hospital-based surveillance program operating throughout Australia.


FluCAN, funded by the Australian Government, monitors flu activity in real-time during each flu season, observing the impact of flu-related admissions on hospitals and handling data that can be valuable in public health decisions. The FluCAN system is based at 15 hospitals nationally.

As part of their work, FluCAN scientists have since 2009 looked at the effectiveness of the annual flu vaccine.

The Australian Government provides free vaccines for at-risk Australians to protect them from severe influenza – elderly people, pregnant women, Indigenous people and those with underlying medical conditions. Immunisation aims to reduce serious morbidity and mortality: flu hospitalises up to 15,000 mostly elderly Australians a year.

“We think it’s important to keep an eye on the vaccine because it changes every year – it’s chasing a moving target,” Professor Cheng said of the changing strains of virus. “So it’s important to show that it does protect people each year,” he said.

The latest figures have been published in two studies which demonstrate that the 2014 trivalent (three-strain) vaccine reduced the risk of hospitalisation by about 51 per cent of adults and was 55 per cent effective for children.

Professor Cheng said figures in previous years, when only adults were taken into account, have been generally between 40-60 per cent.

The study concluded that the influenza vaccine was “moderately protective” against hospitalisation with laboratory-confirmed influenza during the 2014 influenza season.

“It’s fair to say it’s not a perfect vaccine – there’s a lot of research going into making new and better vaccines – but until then we have to keep checking this vaccine and making sure it continues to work.”

A quadrivalent vaccine was used in the 2016 season but researchers were still “crunching numbers” to see how effective it was, he said.

Cheng AC, Kotsimbos T, Kelly PM; FluCAN Investigators. Influenza vaccine effectiveness against hospitalisation with influenza in adults in Australia in 2014. Vaccine. 2015 Dec 16;33(51):7352-6. doi: 10.1016/j.vaccine.2015.10.016. Epub 2015 Oct 31.

Blyth CC, Macartney KK, Hewagama S, Senenayake S, Friedman ND, Simpson G, Upham J, Kotsimbos T, Kelly P, Cheng AC. Influenza epidemiology, vaccine coverage and vaccine effectiveness in children admitted to sentinel Australian hospitals in 2014: the Influenza Complications Alert Network (FluCAN). Euro Surveill. 2016 Jul 28;21(30). doi: 10.2807/1560-7917.ES.2016.21.30.30301.