AusVaxSafety: how Australia monitors vaccine safety in near-real time

Every vaccine on the Australian market has gone through clinical trials before authorisation. Trials are good at detecting common adverse events, but they are too small to detect rare ones, the kind that occur once in 10,000 or once in 100,000 doses. After authorisation, the job of finding those rare signals falls to post-marketing surveillance. Australia’s contribution to that work, AusVaxSafety, is one of the most ambitious active surveillance systems in the world. Coordinated by NCIRS, it changes the safety conversation from “tell us if you have a problem” to “we’re asking everyone.”

Passive vs active surveillance

Most countries rely primarily on passive reporting, healthcare providers and patients submit adverse event reports to a national agency (the TGA, in Australia). Passive systems are essential, but they undercount: many events are never reported, particularly mild ones, and many reports lack the data needed to assess causality.

Active surveillance flips that. The system contacts vaccinated people proactively to ask what happened. Reporting rates jump from a few percent to over 70%. The result is a much clearer signal of background adverse-event rates against which any unusual pattern can be detected.

How AusVaxSafety actually works

1. Enrolment at the point of vaccination. Participating clinics (sentinel GP practices, immunisation services, pharmacies, hospitals) capture mobile numbers at consent.
2. SMS survey, day 3. A short survey asks about specific symptoms, fever, injection-site reactions, severe events, time off work, and whether the person sought medical care.
3. Automated triage. Severe-event responses trigger a follow-up call. Mild reactions are aggregated.
4. Weekly aggregation. Data from tens of thousands of doses per week is cleaned, demographically adjusted, and compared to historical baselines.
5. Signal detection. If a specific event runs significantly above baseline, it is flagged and escalated to the TGA and ATAGI.
6. Public reporting. Weekly safety summaries are published openly during peak seasons.

What AusVaxSafety has changed

Identifying outlier formulations

In 2015, AusVaxSafety detected unusual fever rates in young children receiving one paediatric influenza formulation. The signal was identified within weeks; the affected formulation’s use in young children was paused. Without active surveillance, the signal would have taken months to surface.

Quantifying COVID-19 vaccine safety in real time

During the COVID-19 vaccination rollout, AusVaxSafety collected near-real-time data on millions of doses. The system contributed to identifying the rare thrombosis-with-thrombocytopenia syndrome (TTS) signal early, enabling timely policy adjustments and public communication. Public weekly reports addressed widespread community concern with hard data.

Building the evidence base for special populations

Trials often exclude pregnant people, immunocompromised people, and the very elderly. Active surveillance fills the gap with post-authorisation data on exactly those populations. Pregnancy-specific dashboards for influenza, dTpa, COVID-19 and RSV have been published since 2022.

What AusVaxSafety isn’t

• Not a substitute for individual case reporting. If you experience an unexpected reaction, still report it to SAFEVAC (Victoria) or directly to the TGA. Your individual report is part of the dataset.
• Not a causality machine. Active surveillance detects signals (patterns suggesting a possible link). Confirming causality still requires controlled studies, often with linked clinical data.
• Not a reason to delay vaccination. Several hundred million doses of NIP vaccines have been administered in Australia. The signals that have been confirmed are very rare. The system exists precisely so that if a problem emerges, it is found early.

How it fits with TGA, SAFEVAC and SKAI

The Australian vaccine-safety system is layered. The TGA runs national passive surveillance and is the regulator. SAFEVAC is Victoria’s specialised AEFI clinic and surveillance unit. AusVaxSafety is the active surveillance program at the population level. NCIRS connects these data streams to clinical research and public communication, including through SKAI. Together they produce one of the most robust national vaccine-safety systems in the world.

For a refresher on what to do personally after a vaccination, see our adverse events post.