Our blog is a science blog. It is written by clinicians and scientists with specific expertise in vaccine safety science with the aim of providing evidence-based, informal commentary on current and emerging issues of vaccine safety.

The views are those of the authors and do not necessarily represent or reflect the views of the Co-Directors, Scientific Advisory Committee, or partners of the GVDN®; or UniServices at University of Auckland, Waipapa Taumata Rau.

Our view is that accurate, consistent, and transparent communication about all aspects of vaccine safety and effectiveness is critical for stakeholders from global health agencies to vaccine recipients in their local community.

Vaccinology is a broad field in its own right and draws on a number of pure and applied sciences. All authors are experts in the field of vaccinology and topic they are blogging about. They will bring their own specialist perspectives, including in epidemiology, biostatistics, global health, immunology, infectious diseases, public health, and public policy.

Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD

A growing body of research indicates that COVID-19 vaccines not only reduce the incidence of infection but also significantly decrease all-cause mortality among vaccinated individuals compared to those who are unvaccinated.


Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD and Karin Batty, RN, PGDipPH (Dist)

Vaccines are a cornerstone of public health, providing protection against many infectious diseases. Vaccine safety monitoring is an important aspect of ensuring that vaccines are safe and effective.

Robert T Chen, MD MA

Historically, much of the safety assessment of a new vaccine was deferred to post-introduction. Safety assessments within pre-approval clinical trials tended to be separate from post-approval Real-World evidence (RWE).

Karin Batty, RN, PGDipPH(Dist)

The surge and rapid dissemination of misinformation means it is essential that vaccine communications employ the most effective techniques first time, every time. Debunking is one of these, provision of correct information can be done by experts and non-experts ‘on-the-spot’.

Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD

One of the most perplexing health challenges associated with the COVID-19 pandemic is the enigmatic condition known as long COVID. As the name suggests, it refers to a multitude of symptoms and conditions that persist beyond three-months after someone has been infected with the virus.

Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD

Vaccines authorised for use are incredibly safe, but the risk for serious side effects is not ‘0’. Vaccine safety scientists exist because vaccines are not 100% safe.

Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD

Vaccine safety signals are essential to stimulate questions about the potential relationship between a vaccine and an adverse event.

Bruce Carleton, B.Pharm, Pharm.D, FCP, FISPE

Any adverse outcome from vaccine use is a concern to everyone, from vaccine manufacturers to the people who experience them. Vaccines in a way are like cars – incredibly safe and effective, but not without some risk.

Helen Petousis-Harris, BSc, PGDipSci (Dist), PhD

Given the breadth and magnitude of vaccine safety activities, it is surprising how wide the belief is that the world relies on voluntary reports of adverse events, even among health professionals.