Covid-19 vaccine explainer: The what, when and how of the 2021 rollout

New Zealand began its Covid-19 vaccination programme last month, on February 20. The Government purchased four different types of vaccines but at this stage are only using one type: the Pfizer/BioNTech vaccine.

Everyone in the country over the age of 16 is eligible to get vaccinated but certain groups are prioritised. The first group is Border and Managed Isolation Facility (MIF) and Quarantine (MIQ) workers and the people they live with. There are roughly 50,000 people in this group and just over half of them (27,000) have received the first vaccine so far (as of 17 March 2021.)

How effective is it?
The Pfizer/BioNTech vaccine requires two injections. Following the first injection, it’s 52% effective at protecting people against severe infection from the virus. After the second injection is administered three weeks later, effectiveness increases to 95%.

Does everyone in New Zealand need to be vaccinated before we go back to life as normal?
Not quite, it's all about herd immunity. The idea is that if enough of us in the country are vaccinated, then the virus will be starved of people it can spread to. Even those who aren’t vaccinated will be protected from the disease because they won’t come into contact with it.

So what is the magic number for herd immunity?
This is the big question. Previously it was thought that a country needs to have around 70-75% of their population immunised against Covid-19 to achieve herd immunity, but more recently health experts, including Dr Ashley Bloomfield, believe we should be aiming for 90%.

Why is this a problem?
There are two main issues. Firstly, the Pfizer/BioNTech vaccine is only approved for people over 16. In New Zealand, this roughly equates to a million young kiwis. So that’s 20 percent of our population currently ineligible to be vaccinated.

Secondly, last month a Ministry of Health survey showed 24% of kiwis are “unlikely” to take the vaccine and 16% say they “will not” take the vaccine.  On this basis, New Zealand will not currently achieve 90% population immunity.

Are there solutions to these problems?
Yes, well hopefully.

Trials are underway at the moment to approve the Pfizer vaccine for 12-15 year olds. The pharmaceutical company's CEO says he expects younger teens to be eligible for the vaccine by spring and primary school children by the end of the year.

As for the cynics, the Ministry of Health has started their PR campaign to try to convince them that the vaccine is worth getting.