Health Minister Chris Hipkins said there are two new Covid-19 cases in the community.
The cafeteria in the business at the centre of a Covid-19 community outbreak could be a possible source of transmission as staff from all facets of the company dine together.
A woman who works at LSG Sky Chefs, along with her husband and daughter, tested positive for the virus on Saturday night, sparking the country's rise in alert levels.
Two contacts of the daughter at Papatoetoe High School were also today confirmed to have returned positive results.
While the Ministry still doesn't know the source of the woman's infection, and LSG wouldn't comment as to whether the cafeteria was a possible contamination zone, the company did confirm staff were provided meals and ate them together.
An airport staff member, who did not want to be named, said he feared the communal eating space could be a possible contamination zone as staff regarded as high-risk mingled with lower-risk staff.
"One of the policies at LSG is all staff can't bring in their own food because they're a catering company, for food hygiene purposes. Everyone in the company is provided [meals] and have it at the same given hour when it's ready so maybe she'll be sitting with other workers that deal with aircrew.
"I'm sure, within the premises, that not everybody's going to wear a mask."
A Ministry spokesperson wouldn't confirm if the cafeteria was of interest, stating "a range of scenarios are being investigated, including this workplace".
LSG didn't want to "take part in any speculation", while epidemiologist Professor Michael Baker said a cafeteria was a plausible area of infection given staff from all around the business were in there at the same time.
The LSG spokesperson said although it provided food in its canteen all day during work hours, it had strict rules around the use of masks, physical distancing and hand sanitising.
Staff were not segregated when in the canteen.
"While eating, staff are keeping the necessary physical distance of 2m apart from each other, we have blocked seats for this purpose. There are bins with fresh masks at the exit for our workers.
"There are clear standard processes in place at our catering unit, supporting the adherence to these regulations.
"This means for example that the paths inside the canteen are clearly defined, there are waste bins for used masks at the entrance and all employees must wash their hands before entering the canteen area."
Professor Baker believed the most likely scenario of contamination would be when higher risk staff are mingling with lower risk staff.
"Definitely, any mixing between airside staff and the other staff is a potential mode of transmission and it might have happened there.
"They might have known each other and had a conversation in the corridor, so there's always going to be opportunities and that's why I would hope there's a lot of focus including that setting of transmission."
Baker said investigators were doing "environmental swabbing" for infection in the laundry where the woman worked, "so they are trying to look under all these rocks at the moment".
He also hoped there were rigorous testing regimes in place.
Meanwhile, the union representing airport workers is calling for more "work bubbles" to cut the risk of spreading Covid-19.
The Public Service Association (PSA) said the Aviation Security Service has now split staff into two bubbles at or around Auckland Airport - one group working at the domestic terminal building, and the other at the international terminal.
Staff are assigned to duties in one or the other bubble only, and the goal is for each bubble to be self-sufficient in terms of managing training, and sick and other leave.
