Influenza A Vs B In Australia: What Employers Need To Know For 2026
Influenza A Vs B In Australia: What Employers Need To Know For 2026
Influenza A is more common, crosses species, and has pandemic potential. Influenza B is human-only and often skews younger. In real life, flu A vs flu B symptoms look very similar, and either can sideline teams. From 2026, Australia moves to trivalent influenza vaccines (TIV) — A(H1N1) + A(H3N2) + B/Victoria — with B/Yamagata phased out after no detections since 2020.
By Aitor Aspiazu, Founder & Managing Director / Lead Nurse Consultant (RN), Corporate Care.
“Every winter I’m asked: which flu is worse — A or B? In workplaces, that’s the wrong question. If people are off sick, productivity drops. The wins come from timely vaccination, easy booking, and clear comms.” — Aitor Aspiazu, RN.
The Difference Between Influenza A and B (Fast Facts)
- Virology & Host Range
Influenza A infects humans and animals (birds, pigs), enabling novel subtypes and pandemics. Influenza B is almost exclusively human and does not cause pandemics.
Paules & Subbarao, Lancet • Laporte et al., J Virol - Epidemiology in Australia
A drives most laboratory-confirmed cases and hospitalisations; B typically contributes ~10–20% (season-dependent) and is proportionally higher in older children and young adults.
Sharma et al., BMC Infect Dis • Moa et al., Influenza Other Respir Viruses • Moa et al., PLOS One • Wong et al., BMC Infect Dis - Clinical Picture & Severity
Influenza A vs B symptoms are largely indistinguishable; both are linked with complications (e.g., pneumonia, acute coronary syndromes). There isn’t a reliably “milder” type.
Sharma et al. • Cohen et al., PLOS One - Genetic Diversity & Evolution
A = subtypes H1N1, H3N2 with faster drift/shift. B = B/Victoria and B/Yamagata lineages, slower evolution, and lower within-host diversity.
Laporte et al. • Moa et al. • Valesano et al., J Virol
“Operationally, don’t overthink influenza A vs B. Treat them as equal risks and build a simple pathway to vaccination and sick-leave support.” — Aitor Aspiazu, RN.
Who’s Most Affected In Australia?
- Influenza A: highest burden in the very young and older adults, seen in excess hospitalisation and mortality data.
Moa et al. • Leung et al., Int J Epidemiol - Influenza B: proportionally more common in school-aged children (5–9) and young adults; hospitalised B cases skew younger.
Moa et al. • Wong et al. • Blyth et al., Clin Infect Dis • Sharma et al.
Bottom line: the difference between influenza A and B doesn’t change your workplace response: either can cause clusters and time off.
2026 Update: Trivalent Vaccines (TIV) Replace Quadrivalent
From the 2026 Southern Hemisphere season, Australia will use trivalent influenza vaccines (TIV) comprising A(H1N1), A(H3N2), and B/Victoria. This follows the global move to phase out B/Yamagata from seasonal formulations due to the absence of confirmed detections since 2020.
-> More on the 2026 formulation: Corporate Care explainer — corporatecare.com.au/flu-vaccination/flu-vaccine
(Context for past seasons: Australia has previously seen B-lineage mismatches in roughly a third of seasons, which is why quadrivalent vaccines were important when B/Yamagata circulated.)
Caini et al., PLOS One • Moa et al.
Our workplace flu vaccination services are available in all metropolitan and many regional locations in Australia and New Zealand.
Quick Answers Your Team Will Search
- Which flu is worse: A or B? / Which influenza is worse?
There isn’t a consistent “worst type of influenza”. Severity varies by age and risk factors; flu A vs flu B outcomes overlap.
Sharma et al. • Cohen et al. - What is influenza B (flu type B)?
A human-only influenza type. From 2026, vaccines target the B/Victoria lineage. - What is the difference between influenza A and B / the difference between flu A and B symptoms?
Host range and evolution differ (A has animal reservoirs and pandemic potential; B is human-only). Symptoms are similar for most cases.
Paules & Subbarao • Sharma et al.
How Corporate Care Supports Australian Organisations
- On-site clinics and flu voucher programs for hybrid teams.
- Clinician-written comms and consent so people actually understand what influenza A and B are, what the difference is between influenza A and B, and why vaccination matters.
- Uptake reporting to help leaders plan coverage and reduce avoidable downtime.
Got questions or need more information about flu vaccines? Contact us.
References (Evidence You Can Trust)
- Paules & Subbarao. Lancet (2017)
- Laporte et al. J Virol (2019)
- Sharma et al. BMC Infect Dis (2020)
- Moa et al. Influenza Other Respir Viruses (2017)
- Moa et al. PLOS One (2020)
- Daley et al. J Paediatr Child Health (2000)
- Wong et al. BMC Infect Dis (2019)
- Cohen et al. PLOS One (2015)
- Valesano et al. J Virol (2020)
- Caini et al. PLOS One (2019)
Author & Clinical Oversight: Aitor Aspiazu, RN — Founder & Managing Director / Lead Nurse Consultant at Corporate Care. He authors Corporate Care’s clinical protocols and writes about healthtech and AI tools that support clinicians and clients before, during, and after clinics.
General information only. For personal medical advice, speak with your GP or local health service.
- Behind the Syringe
- Flu Insights
Introducing Aitor Aspiazu, your go-to flu expert and a Registered Nurse accredited by AHPRA (NMW0001159845). Boasting over two decades of experience in healthcare, Aitor has navigated everything from Emergency Departments to Corporate Wellness Programs—and yes, he’s even battled the flu himself. As the Founder and Lead Nurse Consultant at Corporate Care, he’s the driving force behind workplace health and well-being. No longer in scrubs, he’s now at the forefront of healthcare innovation, leveraging Artificial Intelligence and automation to revolutionise workplace health and well-being. As the Founder and Lead Nurse Consultant at Corporate Care, he’s the visionary behind cutting-edge flu vaccination programs that keep businesses running smoothly. Off-duty, he’s a proud dad and a Padel addict who represented Australia in the World Padel Championship. Trust Aitor; he’s got your back when it comes to flu prevention and modern healthcare solutions.