Sixty-one passengers on two Friday flights from South Africa to the Netherlands tested positive for COVID-19, Dutch officials said Saturday.
On Sunday, public health officials confirmed that at least 13 were cases of the omicron variant.
The cases were discovered among passengers who arrived at Amsterdam’s Schipol Airport on KLM flights from Johannesburg and Cape Town, before the Dutch government restricted air traffic from southern African nations because of concerns about the new variant.
The passengers had all either shown proof of vaccination or negative test results before boarding the flights. “We don’t have an explanation” for the high number of cases, a KLM spokesperson said.
After disembarking, passengers were kept separately from other travelers while they were tested and awaited results. Those who tested positive were sent to quarantine at a hotel.
New York Times reporter Stephanie Nolen was on one of the flights, and tweeted that she tested negative — “at least today.”
Tested negative. At least today. After all that time with maskless yellers in an unventilated space - we shall see what the next days bring. Now I sit in the terminal for 10 hours until a flight to YYZ (bets open on something going amiss on that one)
— Stephanie Nolen (@snolen) November 27, 2021
Dutch photographer Paula Zimmerman told Reuters that she did not get her negative test results until 18 hours after landing — and after spending much of that time standing next to a man who tested positive.
“I’ve been told that they expect that a lot more people will test positive after five days,” said Zimmerman, who complained about the disorganized process.
“It’s a little scary, the idea that you’ve been in a plane with a lot of people who tested positive,” she said.
— paula zimmerman (@paula63) November 27, 2021
The Dutch government on Friday announced the nighttime closure of bars, restaurants and most stores in a bid to stem a record wave of COVID cases the country was already facing.
Omicron cases are quickly popping up in more nations, including Italy, Britain, Germany, Hong Kong and Israel. Israel announced Friday that it is closing borders to all foreign travelers, making it the first nation to do so following the emergence of the omicron variant.
Infectious disease expert Dr. Anthony Fauci, President Joe Biden’s chief medical adviser, said Saturday that he suspects the variant is already in the U.S.
The White House announced Friday that it will restrict travel from South Africa and seven other countries on the African continent beginning Monday.
This article originally appeared on HuffPost and has been updated.