Efficacy isn’t the only thing we should consider
It can be helpful to look at the flu vaccine as a contrast. The flu vaccine is far from perfect — it provides moderate protection, with effectiveness varying between different groups of people and from season to season.
For example, in the 2015/16 season in the United States, the quadrivalent influenza vaccine (which covers four strains) was about 54% effective against laboratory-confirmed influenza.
People know it’s not perfect, but people don’t generally judge whether they’ll receive a vaccine based on its effectiveness alone.
We know from talking to the community that many factors influence motivation, especially perceived risk and severity of infection, and confidence in the safety of the vaccine.
Every year, access to flu vaccines is prioritised to those at most risk, such as people with medical conditions, Aboriginal and Torres Strait Islanders and those aged 65 years and older. The public has confidence in this approach.
We need to protect those most at-risk first, and we don’t have an issue doing this day-to-day. We now have a similar challenge with the new COVID vaccines.
The best approach for protecting everyone’s health amid the pandemic is to provide different vaccines to different people according to need and availability, at least in the short term.
The best vaccine is always the one you can get to the communities that need it before they urgently need it.
Australia’s combination strategy
Because Australia is essentially COVID-free at present, it means we’re in a unique situation that permits a “combination” vaccine strategy.
The Pfizer vaccine is perfect for preventing the most extreme outcomes for people at very high risk of infection or disease: people on the frontlines of the fight against COVID and older people or people with high-risk health conditions.
The AstraZeneca vaccine has the ability to protect a large number of people against disease quickly, because we can make it easily and distribute it quickly.