Winter Brings a Wave of Respiratory Illnesses Across Australia

Written by the MediLeave Editorial Team · Medically reviewed by Dr Shamini Rathinam

As temperatures drop, respiratory viruses are on the rise across Australia. If you've recently battled a sore throat, runny nose, persistent cough or even fever, you're far from alone. Hospitals and aged care facilities nationwide are feeling the strain as multiple viruses circulate at once.

Hospitals Under Pressure

The 2025 winter season has placed significant strain on Australia's health system. Recently, several Queensland hospitals paused non-urgent surgeries due to rising cases of influenza and COVID-19.¹ If you're in Queensland and need to take time off to recover, you can get a medical certificate online from an AHPRA-registered doctor. At the same time, COVID outbreaks have been reported in over 200 aged care centres across Australia.²

What's Circulating This Winter Season?

Four major respiratory illnesses are driving the current wave: COVID-19, influenza, RSV, and the common cold. Here's what you need to know about each.

COVID-19

• June surge: Nearly 32,350 COVID cases were reported in June 2025, approaching last year's June figure of 45,634.³
• Undercounting likely: Testing rates have dropped significantly compared to early pandemic years, so true case numbers are likely higher.
• Current variant: NB.1.8.1 ("Nimbus"), a descendant of JN.1, has driven the latest winter wave.⁴
• Symptoms: Classic cold-like signs plus particularly painful sore throats, as well as nausea and diarrhoea.⁵
• Risk groups: Older adults and those with chronic conditions face the highest risk of severe illness.⁶
• Vaccination: Boosters target JN.1 and remain effective against Nimbus and related strains like "Stratus" (XFG).^7,8
• Who should boost: Annual boosters are widely available; people aged 75+ are encouraged to get one every six months.⁹
• Antivirals: Available to people 70+ and at-risk younger Australians who test positive.^10,11

COVID Booster Dose Recommendations, Australia

Source: COVID-19 vaccine advice and recommendations — Australian Government Department of Health, Disability and Ageing

Influenza (Flu)

• Severity: The 2025 flu season has hit hard, with January to May cases up 30% over last year — the highest first-quarter influenza case numbers since the end of the COVID pandemic.¹²
• Symptoms: High fever, muscle aches, fatigue, sore throat and congestion.¹³
• Who's most vulnerable: Elderly, young children and pregnant women.¹⁴

Laboratory Confirmed Cases of Influenza — 2024 vs 2025

Source: NINDSS Dashboard — National Notifiable Diseases Surveillance System

Flu Vaccination Access in Australia¹⁵

• Free for children aged 6 months to 4 years, people 65+, pregnant women and high-risk groups under the National Immunisation Program.
• Free in Queensland and WA for everyone aged 6 months and over; other regions may charge up to A$30.

RSV (Respiratory Syncytial Virus)

• Reporting: Only nationally tracked since 2021, making long-term comparisons difficult.¹⁶
• Case count: June 2025 saw 27,243 cases — on par with June 2024. The peak may have just passed.¹⁷
• Symptoms: Similar to a cold, but can escalate to bronchiolitis and pneumonia, particularly in young children and older adults.¹⁸
• Who's at risk: Infants, elderly, and people with chronic conditions.¹⁸

RSV Treatment & Prevention¹⁹

• A free RSV vaccine is now available for pregnant women to protect newborns up to six months of age.
• A monoclonal antibody injection is offered to at-risk children under two.
• Older adults can access two RSV vaccine brands recommended for:
  • Everyone aged 75 and over
  • At-risk individuals aged 60+
  • Aboriginal and Torres Strait Islander people aged 60+

Note: The adult RSV vaccines cost approximately $300 and are not currently subsidised. Protection lasts at least three years.²⁰

The Common Cold

• Causes: The common cold can be caused by over 200 virus types — mostly rhinoviruses, but also coronaviruses and others.²¹
• Symptoms: Sneezing, congestion, sore throat, fatigue and mild fever.²²
• Frequency: Children average 6 to 8 colds per year; adults typically get 2 to 4.²³
• Treatment: Rest, hydration and over-the-counter remedies. A universal cold vaccine remains elusive due to viral diversity.

How to Stay Safe This Winter

Even minor viruses can cause major disruption to work, study and family life. To protect yourself and others, the Australian Centre for Disease Control recommends:²⁴

• Maintain good hand hygiene practices throughout the day.
• Cover your coughs and sneezes, and teach kids to do the same.
• Wear a high-quality mask if you're at increased risk or visiting vulnerable people.
• Stay home and rest when unwell to avoid spreading illness.
• Stay up to date with recommended vaccinations for flu, COVID-19 and RSV.

Rapid "panel tests" that detect influenza A and B, COVID-19 and RSV are now widely available for home use — useful if you're feeling unwell and want to identify which virus you have.

By taking simple precautions, we can help reduce pressure on healthcare systems and safeguard vulnerable members of our community.

Need a Medical Certificate or Telehealth Consult?

It's easy to get an assessment from a MediLeave Partner Doctor. If suitable, they can provide you with a medical certificate for time off work when you have cold and flu symptoms. Our online medical certificates start from only $15.95.

The process is convenient and hassle-free, right from the comfort of your home:

Please note that the independent Partner Doctor will review your health notes and make an informed decision on whether to issue a medical certificate. The Practitioner does not work for MediLeave; we are designed to facilitate a convenient connection with them.

The content provided is for general informational purposes only and does not constitute medical advice, nor is it a substitute for professional medical consultation. If you are experiencing symptoms or have health concerns, please seek advice from a qualified healthcare professional. The views or recommendations expressed in this article and any linked resources do not necessarily reflect those of MediLeave or its affiliates.