How did we get vaccines so quickly?

This year feels very different from last year, in a good way. While the pandemic continues to rampage around the world, we are starting to see genuinely positive signs of it abating in some places.

There have been many lessons helping public health measures be more effective such as variants of lockdowns, social distancing, PPE and border controls. The exciting newcomer now is the availability of vaccines.

In what was less than a year, we have available licensed Covid-19 vaccines. This is incredible progress and the speed of their development can be credited to an amazing international effort.

So, how have we managed to get vaccines so quickly?

Firstly, science has come a long way since the early days of vaccine development and we have had real breakthroughs in design - particularly with the newer RNA and vector-based vaccines leading the way.

Secondly, international cooperation supported by significant financial backing has helped overcome roadblocks that have traditionally slowed vaccine development. Processes that were previously run sequentially have been run in parallel.

Some of the factors enabling the rapid development of Covid-19 vaccines include:

- The fact that the large pivotal trials were able to enrol large numbers of willing participants easily, and because Covid-19 disease is so prevalent, clinical data was able to be collected very fast.

- Manufacturing plants were established at large cost, taking a financial risk before they knew if the vaccines would work but meant they were ready to scale up production rapidly as soon as the clinical trials show success.

- Authorisation bodies reviewed data as it arrived, to speed up the processes.

Now that vaccines are here, how much of a difference will they make?

We can rightly be excited at this time, because these vaccines are a major step forward we need in managing to control the Covid-19 pandemic long term. However, they are not a panacea to rapidly return to life as we knew it.

For us here in New Zealand, the vaccine we have approved to date (Pfizer-BioNTech) comes with impressive safety and effectiveness data both from the clinical trials and now from extensive use in many, many millions of doses. We can be confident it has an excellent safety profile and it is highly effective against symptomatic disease.

An important question yet to be answered is how much effect this vaccine, or other vaccines New Zealand may approve, will have against reducing spread of the virus. What we do know though is that Covid-19 vaccines help reduce the effects of the pandemic.

While I think it is unlikely we can fully keep this virus out of the country once we open up the borders with a well-vaccinated population, I feel very positive we may be able to keep community spread at a low level.

What a difference a year makes.