New Zealand COVID Outbreak Could Have Come From Frozen Food Packaging

New Zealand health officials are investigating whether imported frozen food packaging could be the source of the country's fresh COVID-19 outbreak.

New Zealand reported four new cases of the virus on Tuesday, with an additional 14 cases being reported on Thursday. One of the initial cases was detected in a worker who handled imported products at a frozen food storage facility. Prior to the outbreak, no new infections had been seen in the country for more than 100 days.

Although officials believe the source of the outbreak is more likely to be an infected person breaching strict border control measures, they are investigating whether the virus could have been brought into the country on frozen food packaging.

"We're not ruling anything out," said Ashley Bloomfield, New Zealand's Director-General of Health, during a Wednesday press conference. "We do know from studies overseas that actually, the virus can survive in some refrigerated environments for quite some time."

An investigation that includes testing surfaces for contamination is taking place at a local facility operated by Americold, a U.S.-based food cold storage and transportation company. Thursday's new cases included three additional workers at the facility, with most of the other cases being family members of the workers.

"We are working directly with the Health Department in New Zealand and the health and safety of our employees remains our top priority," Americold Director of Communications Angie Hansen told Newsweek in a statement. "We aren't going to speculate on how the virus was introduced or its origins."

"The health department's investigation is ongoing and they are ruling out options as they go," added Hansen. "We will continue to cooperate entirely with their efforts."

Frozen Food Aisle
Officials in New Zealand are investigating whether shipments of frozen food destined for supermarkets could have infected workers with COVID-19, although experts believe it is an unlikely source of infection. Prasith_To/Getty

An Americold official told The New Zealand Herald it is "improbable" that the virus could have been spread at the company's facility, noting a series of safeguards that include workers wearing personal protective equipment while handling shipments.

Experts say there is no evidence to suggest the virus is transmitted through food packaging of any sort. It is not clear how long the coronavirus that causes COVID-19 can survive after being frozen, although studies of similar viruses have suggested that it could survive for up to two years.

Amandine Gamble, an infectious disease expert at the University of California, Los Angeles, told Ars Technica that spreading the virus through frozen food packaging would be "unlikely" but "not impossible," due to multiple factors the virus would need to overcome in order to remain viable on a surface while being transported.

"It is very plausible that SARS-CoV-2 can remain viable on frozen surfaces for several days," Gamble told the outlet. "However, it is not clear whether the virus can easily be transmitted via contaminated surfaces ... it would be very bad luck."

New Zealand officials are continuing to investigate the origin of the outbreak while conducting contact tracing to limit any further spread. The country has had one of the world's most successful efforts at containing the virus, with the vast majority of 1,589 total cases, including only 22 deaths, occurring during the early stages of the pandemic.