Several factors may be contributing to this unusual increase, but the main driver is most likely infections with influenza A(H3N2) virus, in particular a new subclade called subclade K. While there is no indication of increased severity of illness, the increase in infections may put increased pressure on our nation’s health care services, as well as increase the risk of serious illness especially in older people, young children, people who are pregnant or breast feeding, Aboriginal and Torres Strait Islander people, and those who have serious medical conditions.
As we move into the holiday season, AHPC recommends the following actions:
- If you are unwell with influenza-like symptoms, stay at home, avoid visiting older people and those with serious medical conditions, and also avoid high risk settings, such as residential aged care homes. If you do need to leave your home, consider wearing a mask to protect other people.
- If you have not received an influenza vaccination in 2025, it is not too late, especially if you are over 65 years of age, your child is 6 months to 5 years old, you identify as Aboriginal or Torres Strait Islander, or you have a chronic health problem. An annual influenza vaccination is recommended for everyone over 6 months of age.
- People travelling to the Northern Hemisphere over the coming weeks should consider receiving an influenza vaccine dose ahead of travel.
- If you are at risk of becoming seriously unwell with influenza, you may wish to speak with your health care provider so you have a plan for getting tested and getting early access to influenza antiviral medication if you get symptoms.
Additionally, for healthcare professionals and aged care providers:
- Be alert for possible influenza outbreaks in institutional settings, including residential aged care homes, correctional centres and hospitals. Follow local outbreak protocols and report outbreaks to your local public health unit.
- Reinforce your service’s infection prevention control measures, ensure clear outbreak action plans are in place, and encourage vaccination for any unvaccinated aged care residents and staff. This is also an opportunity to consider whether aged care residents are due for a COVID vaccine.
- Antiviral medication, like oseltamivir, remains effective against the currently circulating influenza A(H3N2) subclade K virus, and early treatment is recommended for high-risk patients with influenza. Oseltamivir can reduce symptom duration and infectiousness in at risk individuals, and may also be used for outbreak prophylaxis in line with guidance from your local public health unit.
AHPC will continue to monitor influenza infection rates, vaccine effectiveness, and the impacts on our health services, and will update this guidance as needed.