Developing a Covid-19 vaccine is arguably the number one priority of humanity right now – so how are we going, and how well-placed is New Zealand to roll one out once it's developed?
The good news, says immunologist John Fraser, is that Covid-19 is not an especially complicated disease to develop a vaccine for.
"It's a relatively simple virus … the idea is that if you can make antibodies in sufficient quantities and with high enough affinity that they will bind to the spike protein when the virus enters the body … then the virus dies, and you can't get infected.
"That's what we refer to as neutralising immunity – and that's what vaccines try to do: generate that protective immunity in the shortest possible time.
"One of the key elements in designing vaccines [is] making it sufficiently easy to produce, so you can produce enough doses to vaccinate a large number of people."
Normally, a vaccine takes 10 to 15 years to develop; it's possible a Covid-19 vaccine will be available next year, with the development taking just 18 or so months.
In one sense, that shows the remarkable unity of the world's scientific community; but there are also fears that rushing the job could compromise the vaccine's safety.
"The reason developing a vaccine takes so long is it's an incredibly expensive process," says vaccinologist Helen Petousis-Harris.
But because the whole world is working on this at the same time, progress is much faster than it normally would be.
Petousis-Harris says most of the usual checks and balances are being done in advance. That means they're ready to get down to business as soon as new developments in a vaccine arrive.
Essentially, because of the urgency, there's much less time lag in examining the vaccines as they're developed.
But John Fraser says while a vaccine is growing closer by the day, people need to be more realistic in their expectations of what a vaccine will mean for everyday life.
"Many people believe that it is the panacea and a one-shot fix. That's not going to be the case. We're in this for the long haul, and it's going to take a lot of work and a lot of preparation to deal with this effectively.
"We are not out of the woods yet – even if a vaccine appears in six months' time."
