Last month, the number was eight. How many cabin crew have now tested positive to Covid-19 coronavirus is open to speculation as Air New Zealand is refusing to update the figure.
One of those eight is understood to be the cabin crew member associated with the Bluff wedding cluster - the country's biggest with 96 cases including one confirmed death and another that may be linked.
The Herald on Sunday's requests for the current number of positive cases this week were declined.
The union covering aviation is now calling on Air New Zealand's executive to provide information.
The airline claimed it was "in the interests of the privacy and welfare of our employees" not to reveal numbers. It was supporting each affected person and working closely with the Ministry of Health, it said in a statement.
E tū told the Herald it hadn't been informed of the number of positives since March 28, despite seeking answers on behalf of the crew.
A flight crew member told the Herald some found the refusal disconcerting and were worried they might contract the virus overseas and pass it to those in their bubbles.
Currently, air crew are excluded from the blanket requirement for those arriving from overseas to go into Government-controlled quarantine for 14 days.
"The union has now requested information at the executive level and [we] have a commitment the health and safety information we need will be provided," said Savage, Head of Aviation at E tū.
He said a decision needs to be made about keeping the public and crews safe because international flights are still essential.
The union did not support compulsory quarantine.
"A more practical solution is to enhance training, PPE and regulatory oversight and pay operating crew to self-isolate at home every 14 days between flights.
"It is a problem the unions, industry and Government must solve together.
"The airline has responsibilities and crew have no wish to get sick or make anyone sick."
The union was reviewing all the health and safety guidelines for international crew, especially on layovers.
The biggest issue at Air New Zealand right now is the thousands of people including up to 1500 cabin crew facing redundancy, Savage said.
The Herald has learned that the airline does not want to get to a point where it is called on to regularly update numbers and believes staff would be quickly identified by contact tracing if need be.
However, that comes as the Herald revealed scientists are sounding the alarm behind closed doors at the Ministry of Health about its ability to rapidly trace close contacts of Covid-19 cases and an outdated surveillance system - described by one insider as a "dinosaur".
Meanwhile, Qantas staff are exploring options, including a class action alleging the airline failed to adequately protect them against Covid-19, after more than 59 employees became infected along with some family members.
The Flight Attendants' Association of Australia said there was deep dissatisfaction about the way Qantas has handled what they say are the risks, particularly to cabin crew.
Australia's Health Protection Principal Committee has now acknowledged that international cabin crew face a higher risk and issued new guidance to the airlines, as Qantas gears up to begin limited scheduled international flights to Los Angeles, London, Auckland and Hong Kong.
Air New Zealand is running limited services to Sydney, Melbourne, Brisbane, Rarotonga, Niue, Norfolk, and long-haul to Los Angeles, Shanghai and Hong Kong.