A new, less invasive but less effective form of Covid-19 testing will be offered to quarantine staff from next week, according to Covid-19 Response Minister Chris Hipkins.
The saliva testing will be optional for staff members and will be in addition to the mandatory weekly testing.
It's not as sensitive or effective as the nose swabs testing currently used, and will only be offered to staff members working in the quarantine facilities - where people with Covid-19 are staying.
Workers in managed isolation facilities, where new arrivals isolate, will not be offered the extra testing, Hipkins said in a statement today.
"This new precautionary measure is in response to higher rates of infection overseas and the more transmissible variants of Covid-19, and is the latest in a series of added protection measures at the border,” he says.
"They will be offered as an additional screening tool for our highest risk border workers."
Hipkins says the safety of those workers is a "top priority".
"[The saliva testing] could mean we pick up any positive cases among workers at quarantine facilities faster and will provide workers with another layer of assurance."
Covid-19 modeller Michael Plank says the less-sensitive tests mean they'll miss cases, particularly early in infection, but it's still a good idea to bring them in.
"It’s important that the new tests are an addition to existing test requirements, not a replacement," he says.
"The advantage of saliva tests is they are easier and less invasive, which means they can potentially be done more often."
By bringing in the extra saliva tests as well as the weekly swab, Plank says it'll be more likely cases are detected before they can pass the virus on to others.
"This will reduce the risk of a community outbreak."
The saliva testing will be offered to workers at the Auckland Jet Park Hotel quarantine facility from Monday, before being rolled out to the joint managed isolation and quarantine facilities in Wellington and Christchurch.
Presently most border workers are meant to undergo a nasal PCR test every seven to 14 days as well as having daily health checks, to ensure they haven't caught Covid-19 while interacting with international arrivals.
Air New Zealand is also trialling the saliva testing with its workers beginning next week, in partnership with Crown research institute ESR.
It'll compare the accuracy of the tests with existing nasal swabs carried out in the same period.
Last week, the Ministry of Health told 1 NEWS it was investigating whether the saliva PCR testing could be introduced in the community, in addition to the nasal swabs currently used.
Hipkins says the Ministry of Health will "report back" on the role and effectiveness of saliva testing in early March.
New Zealand has had 29 confirmed cases of the new UK variant of Covid-19 and seven of the South African variant.
Both mutations are thought to be more infectious than the initial strain.